Digitized by the Internet Archive in 2014 https://archive.org/details/hondacmx250rebel00shoe Honda CMX250 Rebel Owners Workshop Manual by Pete Shoemark Models covered CMX250 C Rebel. 234 cc. Introduced March 1985 ABCOE l^GHIJ KLMNO PQRST Haynes Publishing Group Sparkford Nr Yeovil Somerset BA22 7JJ England Haynes Publications, Lawrence Drive 861 Newbury Park California 91320 USA Inc Acknowledgements Our thanks are due to NGK Spark Plugs (UK) Ltd who provided information on plug maintenance and electrode conditions, and the Avon Rubber Company who supplied information and technical assistance on tyre © fitting. Haynes Publishing Group 1987 A book in the Haynes Owners Workshop Manual Series Printed by J.H. Haynes & Co. Somerset BA22 7JJ, England Ltd, Sparkford, Mr Yeovil, All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage or retrieval system, without permission in writing from the copyright holder. ISBN 1 85010 372 0 Library of Congress Catalog Number 87-80287 is taken to ensure that the information in correct, no liability can be accepted by the authors or publishers for loss, damage or injury caused by any errors in, or omissions from, the information given. Whilst every care this manual is Contents Introductory pages About this manual Introduction to the Identification Buymg 5 Honda CMX250 Rebel Maintenance techniques, tools and working firsti Motorcycle chemicals and lubricants Troubleshooting Chapter 6 parts Conversion factors Safety 5 6 numbers facilities 7 13 14 15 16 1 Tune-up and routine maintenance 25 Chapter 2 Engine and transmision 38 Chapter 3 Fuel system 82 Chapter 4 Ignition system 91 Chapter 5 Frame and suspension Chapter 6 Wheels, brakes and tires 96 107 Chapter 7 Electrical system 122 Wiring diagram 135 Index 136 About /ts manual this purpose of this procedures to follow It is manual is to help when trouble occurs use the manual to tackle the work yourself. simple jobs, doing it yourself may be quicker than arranging hoped many For within Chapter 1, only the Section and paragraph be given (eg see Section 17, paragraph 6). If the reference is made from another Chapter, the Chapter number is given as well (eg Chapter 1, Section 17, paragraph 6). In each example the paragraph number will be omitted where a whole Section is to be followed or referred to. The photographs used throughout the manual are tied to the text to which they relate by the numbering which appears with each photograph caption. Thus a photograph captioned 5.4b indicates that it relates to Section 5, paragraph 4. The b' denotes that it is one of a sequence of photographs relating to that paragraph. Figure references indicate the Chapter to which they belong, and a numerical sequence (eg Fig, 3 4 means Chapter 3, figure number 4). Figure captions are followed by a Section number which ties the figure the reference you maintain and repair your machine. It can do so in several ways. It can help you decide what work must be done, even if you then choose to have it done by a dealer service department or a repair shop. It provides information and procedures for routine maintenance, and it offers diagnostic and repair The purpose that you will an appointment to get the machine into a shop and making trips to leave and collect it. More importantly, you can avoid the expense of repair shop labor costs. As an added benefit there is the sense of satisfaction and accomplishment that comes with completing a job yourself. to Using the manual The manual divided into Chapters, each of which is Introduction to the Although founded on achieved and larger Honda's its Despite the large market for both step-thru type machines displacement models, there has traditionally been less shown in models of Honda s approach with interest relevant section of text. machine are based on the seated normally and facing forward. Motorcycle manufacturers continually improve and modify their models and as a result there are often changes in the specifications and recommendations Where notified, these are incorporated into our manuals at the earliest opportunity. Even though extreme care is taken during the preparation of this left rider s left or right side or right side of the when manual, neither the publisher nor the author can accept responsibility for any errors in. or omissions from, the information given. Honda CMX250 Rebel success as a motorcycle manufacturer is smaller capacity models, such machines have never quite the same popularity in the US as in many other countries its References to the sub-divided into Sections. The Sections are denoted by headings in bold type between horizontal lines. Within each Section, the text is divided into consecutively numbered paragraphs This provides a simple and accurate method of locating a particular procedure. Major procedures, once described in the text, are not normally repeated, but where necessary will be referred to from elsewhere in the manual. For example, if a procedure described in Chapter 1, Section 17, paragraph 6 is to be followed, a reference to it will be included. If is is reference will the Rebel s size and displacement. the Rebel has been to offer a basically simple four-stroke twin of moderate power output and weight. To build a more appealing package, the Rebel has been the subject of a which is quite effective, both terms of appearance and function. The back-to-basics approach has produced an essentially simple motorcycle which is relatively light in weight and easy to work on, access to most areas being unrestricted. A further major benefit is the low seat height, making motorcycle ownership accessible to shorter riders. In particular, the Rebel provides an easily-handled package to the woman rider to whom the choice of machines is often very very careful styling exercise, the result of in restricted. Identification numbers The Honda CMX250 Rebel models have a Vehicle Identification Number (VIN) stamped into a plate rivetted to the steering head area of the frame, just behind the headlight. This number is normally required and licensing of the vehicle. The frame serial number is the same as the Vehicle Identification Number and is stamped into the right side of the steering head column. The engine serial number is stamped into a boss on the left side of the for registration VIN plate gives frame number Frame number head details is crankcase, just below the gearchange linkage. These numbers should be recorded and kept in a safe place so that they can be furnished to law enforcement officials in the event of theft. The frame and engine serial numbers, and the carburetor identification number should also be kept in a handy place, such as with your driver s license, so that they are always available when purchasing or ordering parts for your machine. stamped into the steering Engine number is stamped into boss on crankcase (cover removed for clarity) Buying parts Locate and record all the identification numbers as described under the Identification numbers heading, and take them with you when ordering or buying parts or accessories. The manufacturer may make modifications to a model during its production run, or may obtain some components from the only way Whenever dealer a number of different suppliers. possible, take the when Using the numbers is to be certain of getting the correct part for your machine. worn or damaged placing the order, so that a direct you to the comparison can be part with made. The two places that stock parts for your machine are the franchised dealer and the accessory store. The two differ in that the dealer can supply or order any part for your machine. The accessory store carries only a limited stock of fast-moving items, such as tires, shock absorbers, tune-up parts, various gaskets, cables, brake parts, etc. If the machine is covered by the manufacturer s warranty, always use original may be invalidated. Even after the warranty some non-standard items may fit badly, or may not work properly. Be wary of items like brake pads of unknown manufacture your life may depend on items like this. In some cases it may be worth thinking about buying used parts parts or the warranty period, from new; a wrecker. Items like instrument panels or seats can be expensive the price of a new one. Remember that machines are in the wrecker's yard for a reason, often after an accident. As a general rule, avoid brake, steering or suspension parts unless you can be sure that they are safe - you cannot always see fatigue or hairline cracks which might be present in an apparently good a used equivalent may cost half part. Whether buying new or used, deal with a local supplier with and one who specializes in your make of machine. reputation, a good Maintenance techniques, tools and working facilities Basic maintenance techniques threaded There are a number of techniques involved in maintenance and repair that will be referred to throughout this manual. Application of these techniques will enable the amateur mechanic to be more efficient, better organized and capable of performing the various tasks properly, which will ensure that the repair job is thorough and complete. Specifications. Fastening systems and screws used to hold two or few things to keep in mind when Almost all of them use a locking device of Fasteners, basically, are nuts, bolts more parts together. There are a working with fasteners. some type (either adhesive). All a lock washer, locknut, threaded fasteners should wrench bolts with fits. new Develop the habit be clean, straight, have the hex head where of replacing all damaged nuts and ones. Rusted nuts and bolts should be treated with a penetrating fluid to ease removal and prevent breakage. Some machines use turpentine in a spout type oil can, which works quite well. After applying the rust penetrant, let it 'work' for a few minutes before trying to loosen the nut or bolt. Badly rusted fasteners may have to be chiseled off or removed with a special nut breaker, available at tool stores. If a bolt or studs break off in an assembly, it can be drilled out and removed with a special tool called an E-Z out. Most dealer service departments and motorcycle repair shops can perform this task, as well as others (such as the repair of threaded holes that have been stripped out). Flat washers and lock washers, when removed from an assembly, should always be replaced exactly as removed. Replace any damaged washers with new ones. Always use a flat washer between a lock washer and any soft metal surface (such as aluminum), thin sheet metal or plastic. Special locknuts can only be used once or twice before they lose their locking ability and must be replaced. Torquing sequences and procedures When threaded fasteners are tightened, they are often tightened to is a twisting force). Over-tightening the fastener can weaken it and cause it to break, while under tightening can cause it to eventually come loose. Each bolt, depending on the material it s made of, the diameter of its shank and the material it is a specific torque value (torque reversed. locking tab or thread undamaged threads and undamaged corners on the has a specific torque value, which is noted in the Be sure to follow the torque recommendations closely. Fasteners laid out in a pattern (eg cylinder head bolts, engine case bolts) must be loosened or tightened in a sequence to avoid warping the component. Initially, the bolts/nuts should go on finger-tight only. Next, they should be tightened one full turn each, in a criss-cross or diagonal pattern. After each one has been tightened one full turn, return to the first one tightened and tighten them all one half turn, following the same pattern. Finally, tighten each of them one quarter turn at a time until each fastener has been tightened to the proper torque. To loosen and remove the fasteners the procedure would be into, Disassembly sequence Component disassembly should be done with care and purpose to go back together properly during reassembly. Always keep track of the sequence in which parts are removed Take note of special characteristics or marks on parts that can be installed more than one way (such as a grooved thrust washer on a shaft). It s a good idea to lay the disassembled parts out on a clean surface in the order that they were removed. It may also be helpful to make sketches or take instant photos of components before removal. When removing fasteners from a component, keep track of their locations. Sometimes threading a bolt back in a part, or putting the washers and nut back on a stud, can prevent mixups later. If nuts and help ensure that the parts bolts cannot be returned to their original locations, they should be kept or a series of small boxes. A cupcake or muffin purpose, since each cavity can hold the bolts and nuts from a particular area (eg engine case bolts, valve cover bolts, engine mount bolts). A pan of this type is especially helpful when working on assemblies with very small parts (such as the carburetors and the valve train). The cavities can be marked with paint or tape to identify the contents. Whenever wiring looms, harnesses or connectors are separated, it's a good idea to identify the two halves with numbered pieces of masking tape so they can be easily reconnected. in a compartmented box tin is ideal for this Gasket sealing surfaces Throughout any engine, gaskets are used to components and keep lubricants, surfaces between pressure contained in an assembly. seal fluids, the mating vacuum or Maintenance techniques, tools and working 8 Many times these gaskets are coated with a liquid or paste type gasket sealing compound before assembly. Age, heat and pressure can sometimes cause the two parts to stick together so tightly that they are very difficult to separate. In most cases, the part can be loosened by striking It with a soft-faced hammer near the mating surfaces. A regular hammer can be used if a block of wood is placed between the hammer compared facilities to the spiraling costs of routine maintenance and repair, it is a wise one. To help the owner decide which tools are needed to perform the tasks detailed in this manual, the following tool lists are offered: remain smooth). If prying is absolutely necessary, use a piece of wood, but keep in mind that extra clean-up will be necessary if the wood Maintenance and minor repair. Repair and overhaul and Special The newcomer to practical mechanics should start off with the Maintenance and minor repair tool kit, which is adequate for the simpler jobs. Then, as confidence and experience grow, the owner can tackle more difficult tasks, buying additional tools as they are needed Eventually the basic kit will be built into the Repair and overhaul tool set. Over a period of time, the experienced do-it-yourselfer will assemble a tool set complete enough for most repair and overhaul procedures and will add tools from the Special category when it is felt that the expense is splinters. justified part. Do not hammer on cast parts or parts that could be easily damaged With any particularly stubborn part, always recheck to make and the sure that every fastener has been removed. Avoid using a screwdriver or bar to pry apart components, as they can easily mar the gasket sealing surfaces of the parts (which must must be carefully scraped off and the gasket surfaces cleaned Stubborn gasket material can be soaked with a gasket remover (available in aerosol cans) to soften it so it can be easily scraped off. A scraper can be fashioned from a piece of copper tubing by flattening and sharpening one end. Copper IS recommended because it is usually softer than the surfaces to be scraped, which reduces the chance of gouging the part. Some gaskets can be removed with a wire brush, but regardless of the method used, the mating surfaces must be left clean and smooth. If for some reason the gasket surface is gouged, then a gasket sealer thick enough to fill scratches will have to be used during reassembly of the components. For most applications, a non-drying (or semi-drying) gasket sealer is by the frequency of use. After the parts are separated, the old gasket repair tool kit should be considered the minimum required for performance of routine maintenance, servicing and minor repair work. We recommend the purchase of combination wrenches (box end and open end combined in one wrench); while more expensive than open-ended ones, they offer the advantages of both types of wrench. Combination wrench set (6 to 22 mm) Adjustable wrench - 8 in Spark plug socket (with rubber insert) Spark plug gap adjusting tool The tools Hose removal to the spigot. Then, with slip )oint pliers, grab the rotate set Standard screwdriver tips hose at the back and forth until it is completely free, then pull it off (silicone or other lubricants will ease removal if they can be applied between the hose and the outside of the spigot). Apply the same lubricant to the inside of the hose and the outside of the spigot to simplify installation. If a hose clamp is broken or damaged, do not reuse it. Also, do not reuse hoses that are cracked, it gauge Valve adjustment wrench Hose removal precautions closely parallel gasket removal precautions. Avoid scratching or gouging the surface that the hose mates against or the connection may leak. Because of various chemical reactions, the rubber in hoses can bond itself to the metal spigot that the hose fits over To remove a hose, first loosen the hose clamps that clamp and in this list mm Feeler best secure Maintenance and minor it around the spigot. Work it Combination w in x 2 x 6 6 in) in) (slip-joint) pliers - 6 in Hacksaw and assortment of blades Tire pressure gauge Control cable pressure luber Grease gun Oil can Fine emery cloth Wire brush Hand impact screwdriver and bits Funnel (medium Safety goggles Drain pan Note: Since basic split or torn. (^/ Phillips screwdriver (No. size) plans to maintain and repair a motorcycle For the owner who has few tools, if any, the initial investment might seem high, but when ignition timing checks are a part of routine maintenance, it will be necessary to purchase a good quality, inductive pickup stroboscopic timing light Although it is included in the list of Special tools, it is mentioned here because ignition timing checks cannot be made without one. Spark plug gap adjusting tool Feeler Tools A selection of good tools is a basic requirement for anyone who gauge set Maintenance techniques, tools and working Hand impact screwdriver and Control cable pressure luber Repair and overhaul tool set Pliers Pliers - needle nose snap -ring (internal and external) Cold chisel Scriber 'I2 in Scraper (made from flattened copper tubing) Centerpunch Pin punches (^Ii6, 'Is, ^lie in) Steel rule I straightedge - 12 in Allen wrench set (4 to 70 Clutch holding tool Pin -type spanner wrench A selection of files Wire brush (large) Reversible ratchet Extension - 6 in mm Universal joint Ball (left - mm) Note: Another tool which is often useful is an electric drill motor with chuck capacity of ^Is inch (and a set of good quality drill bits) 3x8 in) click type, right 2) Pliers - lineman's Socket set(s) Torque wrench (same size drive as sockets) peen hammer - 8 oz Soft- faced hammer (plastic/rubber) Standard screwdriver in x 6 in) Standard screwdriver (stubby - ^/i6 in) No Pliers - vise grip inch drive set). Torque wrenches bits Phillips screwdriver (stubby - These tools are essential for anyone who plans to perform major repairs and are intended to supplement those in the Maintenance and minor repair \oo\ kit. Included is a comprehensive set of sockets which, though expensive, are invaluable because of their versatility (especially when various extensions and drives are available) We recommend the •'/s inch drive over the V2 inch drive for general maintenance and repair (ideally, the mechanic would have a ^/s inch drive set and a V2 Phillips screwdriver (No. 9 facilities a - beam type) Circlip pliers (top - external, bottom - internal) Maintenance techniques, tools and working 10 facilities and sockets) because they won't last very long The expense involved in replacing cheap tools will eventually be greater than the initial cost of quality tools. Care and maintenance of tools makes sense Good tools are expensive, so it to treat them with Keep them clean and in usable condition and store them properly when not in use. Always wipe off any dirt, grease or metal chips before putting them away. Never leave tools lying around in the work area. Some tools, such as screwdrivers, pliers, wrenches and sockets, can be hung on a panel mounted on the garage or workshop wall, while others should be kept in a tool box or tray. Measuring instruments, gauges, meters, etc. must be carefully stored where they cannot be damaged by weather or impact from other tools. When tools are used with care and stored properly, they will last a very long time. Even with the best of care, tools will wear out if used frequently. When a tool is damaged or worn out, replace it; subsequent jobs will be safer and more enjoyable if you do. respect. Working facilities Not to be overlooked when discussing tools is the workshop. If anything more than routine maintenance is to be carried out, some sort Allen wrenches (left) and Allen head sockets of suitable (right) Special tools The tools in this list include those which are not used regularly, are expensive to buy, or which need to be used in accordance with their manufacturer's instructions. Unless these tools will be used frequently, it is not very economical to purchase many of them. A consideration would be to split the cost and use between yourself and a friend or friends. and instruments widely available to the public, as well as some special tools produced by the vehicle This list primarily contains tools departments. As a result, manufacturer's special tools are occasionally included in the text of this manual. Generally, an alternative method of doing the job without the special tool is offered. However, sometimes there is no alternative to their use. Where this is the case, and the tool cannot be purchased or borrowed, the work should be turned over to the dealer service department or a repair shop. Valve spring compressor Piston ring removal and installation tool Piston pin puller Telescoping gauges Micrometer(s) and I or dial/vernier calipers Cylinder surfacing hone Cylinder compression gauge Dial indicator set Multimeter Crankcase separation tool Flywheel (AC generator I magneto rotor) puller Stroboscopic timing light Work light with extension cord Small air compressor with blow gun and tire chuck manufacturer references for distribution to dealer service to the Buying tools For the do-it-yourselfer who is just starting to get involved work area is etc. is which soon become necessary. Sometimes waste oil and fluids, drained from the engine purpose. Always keep a supply of old newspapers and clean rags available. Old towels are excellent for mopping up spills. Many mechanics use rolls of paper towels for most work because they are readily available and disposable. To help keep the area under the machine clean, a large cardboard box can be cut open and flattened to protect the garage or shop floor. Whenever working over cover it a painted surface (such as the fuel tank) with an old blanket or bedspread to protect the finish. in repair, there are a can usually be bought saving over the individual with a tool box). As additional tools are needed, add-on sets, individual tools and a larger tool box can be purchased to expand the tool selection. Building a tool set gradually allows the cost of the tools to be spread over a longer period of time and gives the mechanic the freedom to choose only those tools that will actually be used. Tool stores and Honda dealers will often be the only source of some of the special tools that are needed, but regardless of where tools are bought, try to avoid cheap ones (especially when buying screwdrivers set tool prices (and they often or other systems during normal maintenance or repairs, present a disposal problem. To avoid pouring them on the ground or into a sewage system, simply pour the used fluids into large containers, seal them with caps and take them to an authorized disposal site or service station. Plastic jugs (such as old antifreeze containers) are ideal for this number of options available when purchasing tools. If maintenance and minor repair is the extent of the work to be done, the purchase of individual tools is satisfactory. If, on the other hand, extensive work is planned, it would be a good idea to purchase a modest tool set from one of the large retail chain stores. A maintenance and essential. understood, and appreciated, that many home mechanics do not have a good workshop or garage available and end up removing an engine or doing major repairs outside (it is recommended, however, that the overhaul or repair be completed under the cover of a roof). A clean, flat workbench or table of comfortable working height is an absolute necessity. The workbench should be equipped with a vise that has a jaw opening of at least four inches As mentioned previously, some clean, dry storage space is also required for tools, as well as the lubricants, fluids, cleaning solvents, It at a substantial come Valve spring compressor Dial indicator set Cylinder surfacing hone 1 Conversion factors Length (distance) Inches X X X (in) Feet (ft) Miles — 25.4 0.305 .609 1 Millimetres (mm) — Metres (m) — Kilometres (km) X 0.0394 X X 0 621 — Inches (in) — Feet (ft) — Miles 0061 = Cubic inches (cu Volume (capacity) Cubic inches (cu in; in^) Imperial pints (Imp pt) imperidi quaris ^triip Imperial quarts (Imp qt) US quarts (US qt) Imperial gallons (Imp gal) Imperial gallons (Imp gal) Uo gallons (Uo gai) Mass (weight) Ounces (02) Pounds (lb) X X Y A Y A X X Y A Y A 16.387 0 568 X X 28.35 0.454 — Grams X X X 0.278 4.448 — X 0.070 — X 0.068 — 1.10/ .zu 1 (ozf, oz) (Ibf, lb) Newtons (N) zU ( ^ Litres (1) /.i^ll*-»r»c gallons Litres ( (cc, cm^) ^ ) (1) IC Uo Q "7QR 1 1 j-tii^i-tcquaris Litres 1 l\ IC \\jz> qx; (\ IC (Uo X X Y A Y A X X Y A Y A gaij } (g) Kilograms (kg) Newtons (N) Newtons (N) Kilograms-force (kgf; kg) 0.1 (psi; Ibf/in^; Ib/in^) Pounds-force per square inch LIitroc ir Co 1 1 Pressure Pounds-force per square inch (1) 1 0.946 4.546 1 Litres IC Uo 1 Force Ounces-force Pounds-force Cubic centimetres Kilograms-force per square centimetre (kgf/cm^; kg/cm^) Atmospheres (atm) 3.281 76 vj. oo U.Ooo 1.057 0.22 U.Ooo Pounds-force per square inch X 0.069 X 6.895 Kilopascals (kPa) X 0.01 Millibar (mbar) X X 100 0.0145 Pounds-force per square inch _ Kilopascals (kPa) imperidi LjUdtib ^inip = us quarts (US qt) = Imperial gallons (Imp gal) imperial gaiions ^imp gaij Uo X X 0.035 Ounces Pounds X X X 3.6 0 225 9 81 — Newtons (N) X 14 223 — Pounds-force per square inch X 14 696 — 2 205 X Bars in^) U. ZD'f (psi; Ibf/in^; Ib/in^) (psi; Ibf/in^; Ib/in^) in; Imperial pints (Imp pt) Imnpripl iiii|jciicii nii;^rtQ L^uaiio Mmn ^iMi^ r\\\ 1 14.5 ^uo gdiioiib (oz) (lb) — Ounces-force — Pounds-force — _ gaij (ozf; oz) (Ibf; lb) (psi; Ibf/in"; lb/in") Pounds-force per square inch (psi; Ibf/in^- Ib/in^) Pounds-force per square inch Ibf/m^ Ib/in^) Pounds-force per square inch (psi; X 0.145 X 98.1 — Kilopascals (kPa) X X 0.01 = 68.947 (psi; Ibf/in^ Ib/in^) (psi, Ibf/in^ lb/in=^) Millibar (mbar) Kilograms-force per square centimetre (kgf/cm^; kg/cm^) Pascals (Pa) Pounds-force per square inch Millibar (mbar) Millibar (mbar) (psi; lbf/ln^ Ib/in^) Millibar (mbar) Millibar (mbar) (mmHg) Millimetres of mercury Inches of water (inH^O) X X X X Millimetres of mercury 0.75 1 1 .40 .868 _ 27.68 (mmHg) Inches of water (inH^O) Inches of water (inH 0) Pounds-force per square inch X X X X 333 Millibar (mbar) 0.714 0.535 0 036 Millibar (mbar) 1 Millimetres of mercury (mmHg) Inches of water (inH^O) (psi, Ibf/in^ Ib/in^) Torque (moment of force) Pounds-force inches X 0 868 X 8 85 X 12 = Kilograms-force metres (kgf m; kg m) Newton metres (Nm) = Kilograms-force metres (kgf m, kg m) X 7.233 = X X 0.738 9.804 = Newton metres (Nm) X 1 X 0.1 X 0.083 — Pounds-force .1 52 Kilograms-force centimetre (kgf cm, kg cm) Newton metres (Nm) (Ibf in; lb in) Pounds-force inches 1 3 Pounds-force inches (Ibf (Ibf in; lb in) Pounds-force inches (Ibf Pounds-force feet (Ibf Newton metres (Nm) lb in) (Ibf in; lb in) feet (Ibf ft; lb ft) (Ibf in; lb in) Pounds-force feet m; Pounds-force inches Pounds-force inches Hhf in lb inl Pounds-force feet (Ibf ft; lb ft) Pounds-force ft, lb ft) ft; lb ft) X 0.138 ft, lb ft) X X 0.102 X 745.7 = Watts (W) X 0.0013 X 1.609 = Kilometres per hour (km/hr; kph) X 0.621 Miles per hour (miles/hr; X 0.354 0.425 Kilometres per litre (km/I) X Kilometres per litre (km/I) X 2.825 2.352 Miles per gallon, Imperial (mpg Miles per gallon, US (mpg) 1 .356 Power Horsepower (hp) Velocity (speed) Miles per hour (miles/hr; mph) = Horsepower feet (Ibf (hp) mph) Fuel consumption* Miles per gallon. Imperial (mpg) Miles per gallon, US (mpg) X Temperature Degrees Fahrenheit 'It IS = (°Cx1.8) -1- 32 Degrees Celsius (Degrees Centigrade; °C) common practice to convert from miles per gallon (mpg) to litres/ 100 kilometres mpg (Imperial) x HI 00 km = 282 and mpg (US) x IjlOO km = 235 where (1 11 00km), = (°F - 32) x 0.56 Safety First! Professional motor mechanics are trained in safe working proce- However enthusiastic you may be about getting on with the job hand, do take the time to ensure that your safety is not jeopardized. dures. in A moment s lack of attention can result in an accident, as can failure to recognize simple safety precautions. The possibility of an accident will always exist, and the following points do not pretend to be a comprehensive list of all dangers; they are intended rather to make you aware of the risks and to encourage a safety-conscious approach to all work you carry out on your machine. Essential DON'T DOs and DON'Ts the engine without first checking to see if the transmission is in Neutral. DON'T use gasoline for cleaning parts. DON'T attempt to drain oil until you are sure it has cooled to the point that It will not burn you. DON'T touch any part of the engine or exhaust system until they have cooled down sufficiently to avoid burns. DON'T allow brake fluid or antifreeze to contact the machines start paintwork or plastic components. DON'T syphon toxic liquids such as gasoline, antifreeze and brake fluid by mouth, or allow them to remain on your skin. DON'T inhale dust - it may be injurious to health (see Asbestos heading). DON'T allow any spilled oil or grease to remain on the floor - wipe it up before someone DON'T cause use loose slips fitting on it. wrenches or other tools which may slip and DON'T push on wrenches when loosening or tightening nuts or bolts. Always try to pull the wrench towards you. If the situation calls for pushing the wrench away, push with an open hand to avoid scraped knuckles if the wrench should slip. DON'T attempt to lift a heavy component which may be beyond your someone to help you. rush or take unsafe shortcuts, to finish a job. allow children on or around the motorcycle while you are capability - get working on it. DO wear eye protection when using power tools such as keep loose clothing and long bench hair well out of the way of moving parts. DO make adequate DO make sure that any hoist used has a safe working load rating to health. If in doubt, assume that they do contain Fire Remember at all times that gasoline is highly flammable Never smoke, or have any kind of open flame around, when working on your machine. But, the risk does not end there - a spark caused by an electrical short-circuit, by two metal surfaces contacting each other, or even by static electricity built up in your body under certain conditions, can ignite gasoline vapors, which in a confined space are highly explosive. Do not, under any circumstances, use gasoline for cleaning parts, use an approved safety solvent. Always disconnect the battery ground cable before working on any part of the fuel or electrical system, and never risk spilling fuel on to a hot engine or exhaust system component. It IS highly recommended that a fire extinguisher of a type suitable and electrical fires be kept handy in the garage or workplace times. Never try to extinguish a fuel or electrical fire with water for fuel all at Fumes Certain fumes are highly toxic and can quickly cause unconsciousness and even death if inhaled to any extent. Gasoline vapor falls into this category, as do the vapors from some cleaning solvents. Any draining or pouring of such volatile fluids should be done in a well ventilated area. When using cleaning fluids and solvents, read the instructions on the container carefully Never use materials from unmarked containers. Never run the engine in an enclosed space such as a garage: exhaust fumes contain carbon monoxide which is extremely poisoleast If you need to run the engine, always do so in the open have the rear of the machine outside the work area. air or at The battery Never create a spark, or allow a bare light bulb near the battery vent hose It will normally be giving off a certain amount of hydrogen gas, which is highly explosive. Always disconnect the battery ground cable before working on the fuel or electrical systems. possible, loosen the filler battery from an external source. plugs or cover when charging the not charge at an excessive rate or Do the battery may burst Take care when adding water and when carrying the battery. The electrolyte, even when diluted, is very corrosive and should not be allowed to contact clothing or skin. for the job. sure that the machine is securely supported, especially when removing wheels. DO get someone to check on you periodically when working alone. DO carry out work in a logical sequence and make sure that everything assembled and tightened. remember that your motorcycle s safety affects that of others. If in doubt on any point, get professional advice. is hazardous If drill, grinder etc. DO is asbestos. nous. injury DON'T DON'T It correctly DO yourself and Household current When using an electric power tool, inspection light etc., which operates on household current, always make sure that the tool is correctly connected to its plug and that, where necessary, it is properly grounded. Do not use such items in damp conditions and, again, do not create a spark or apply excessive heat in the vicinity of fuel or fuel vapor. Secondary ignition system voltage A severe electric shock can result from touching certain parts of the system (such as the spark plug wires) when the engine is Asbestos ignition such as Certain friction, insulating, sealing, and other products brake linings, clutch linings, gaskets, etc - contain asbestos. Extreme care must be taken to avoid inhalation of dust from such products since running or being cranked, particularly if components are damp or the insulation is defective. Where an electronic ignition system is in use, the HT voltage is much higher and could prove fatal. Motorcycle chemicals and lubricants A number of chemicals and lubricants are available for use during motorcycle maintenance and repair. They include a wide variety of products ranging from cleaning solvents and degreasers to lubricants and protective sprays for rubber, plastic and vinyl. Cleaners Carburetor cleaner varnish and carbon. which and choke cleaner Most carburetor is a strong solvent for cleaners gum leave a gum, dry-type Because of this film it is not recommended for use on electrical components. Brake system cleaner is used to remove grease and brake fluid from the brake system where clean surfaces are absolutely necessary It leaves no residue and often eliminates brake squeal caused by lubricant film will not harden or up. contaminants. Electrical cleaner removes oxidation, corrosion and carbon deposits from electrical contacts, restoring full current flow. It can also be used to clean spark plugs, carburetor jets, voltage regulators and other parts where an oil-free surface is desired. Demoisturants remove water and moisture from electrical components such as alternators, voltage regulators, electrical connectors and fuse blocks. It is non-conductive, non-corrosive and non-flammable. Degreasers are heavy-duty solvents used to remove grease from the outside of the engine and from chassis components. They can be sprayed or brushed on, and depending on the type, are rinsed off either with water or solvent. Lubricants Motor oil is the lubricant formulated for use in engines. It normally contains a wide variety of additives to prevent corrosion and reduce foaming and wear. Motor oil comes in various weights (viscosity ratings) from 5 to 80. The recommended weight of the oil depends on the season temperature and the demands on the engine. Light oil is used in cold climates and under light load conditions. Heavy oil is used in hot climates and where high loads are encountered. Multi-viscosity oils are designed to have characteristics of both light and heavy oils and are available in a number of weights from 5W-20 to 20W-50. Gear oil is designed to be used in differentials, manual transmissions and transfer cases, as well as other areas where high-friction, high-temperature lubrication is required. High temperature wheel bearing grease is designed to withstand the extreme temperatures encountered by wheel bearings in disc brake equipped vehicles. It usually contains molybdenun disulfide (moly), which is a dry-type lubricant. White grease is a heavy grease for metal to metal applications where water is a problem White grease stays soft under both low and high temperatures (usually from -100°F to -i-190°F), and will not wash off or dilute in the presence of water. Assembly lube is a special extreme pressure lubricant, usually containing moly, used to lubricate high-load parts such as main and rod bearings and cam lobes for initial start-up of a new engine. The assembly lube lubricates the parts without being squeezed out or washed away until the engine oiling system begins to function. Chain lubricants are formulated especially for use on final drive chains. Chain lube adheres well and has good penetrating qualities. It and on the side plates, pins Most chain lubes are either the foaming type or quick drying type and are usually marketed as sprays. Ensure that only a is effective as a lubricant inside the chain and rollers. lubricant suitable for 0-ring chains is used. Silicone lubrrcants are used to protect rubber, plastic, vinyl and nylon parts. Graphite lubricants are used where oils cannot be used due to contamination problems, such as in locks. The dry graphite will lubricate metal parts while remaining uncontaminated by dirt, water, oil or acids. It is electrically conductive and will not foul electrical contacts in locks such as the ignition switch Moly penetrants loosen and lubricate frozen, rusted and corroded fasteners and prevent future rusting or freezing. Heat-sink grease is a special electrically non-conductive grease that is used for mounting HE! ignition modules where it is essential that heat be transferred away from the module. Chemicals Anti-seize compound prevents seizing, galling, cold welding, rust and corrosion in fasteners. High temperature With copper and graphite lubricants, is used anti-seize, usually for made exhaust system and manifold bolts. Anaerobic locking compounds are used to keep fasteners from and cure only after installation, in the absence of air. Medium strength locking compound is used for small nuts, bolts and screws that you expect to be removing later. High strength locking compound is for large nuts, bolts and studs which you don't intend to be removing on a regular basis. Oil additives range from viscosity index improvers to chemical treatments that claim to reduce internal engine friction. It should be noted that most oil manufacturers caution against using additives with vibrating or working loose, their oils. Gas additives perform several functions, depending on their chemical makeup. They usually contain solvents that help dissolve gum and varnish that build up on carburetor and intake parts. They also serve to break down carbon deposits that form on the inside surfaces of the combustion chambers Some additives contain upper cylinder lubricants for valves and piston rings, and other chemicals to remove condensation from the gas tank. Other Brake fluid is specially formulated hydraulic fluid that can withstand the heat and pressure encountered in brake systems. Care must be taken that this fluid does not come in contact with painted surfaces or plastics. An opened container should always be resealed to prevent contamination by water or dirt. Waxes and polishes are used to help protect painted and plated surfaces from the weather. Different types of paint may require the use of different types of wax and polish. Some polishes utilize a chemical or abrasive cleaner to help remove the top layer of oxidized (dull) paint on older vehicles. In recent years many non-wax polishes that contain a wide variety of chemicals such as polymers and silicones have been introduced. These non-wax polishes are usually easier to apply and last longer than conventional waxes and polishes. 5 9 1 Troubleshooting Contents Introduction Starter 1 Gear shift difficult or Jumping out motor problems impossible of gear Overselection motor not rotating Starter motor rotates but engine does not turn over Starter motor and clutch function but engine will not 3 turn over 4 2 Starter Abnormal engine noise Knocking or pinging 31 Valve noise or tapping from cylinder head Other noises 32 33 5 Fuel not reaching cylmder 6 Abnormal transmission noise Engine flooding 7 No spark at Weak spark 8 Clutch noise Transmission noise plug at plug 10 General causes Poor handling or roadholding speed Directional instability 12 13 14 Acceleration poor General causes Poor running or lack of power Weak spark at plug or erratic firing Fuel/air mixture incorrect at or right 1 20 Fuel/air mixture incorrect 21 Lubr^cation inadequate 22 23 Clutch operating problems shift Front fork judder when braking Poor rear suspension performance 42 43 Rear suspension noise problems Brakes are spongy or ineffective - disc brakes Brakes drag - disc brakes Brake lever or pedal pulsates in operation - disc brakes Disc brake noise Brakes are spongy or ineffective - drum brakes Brake drag - drum brakes Brake lever or pedal pulsates in operation - drum brakes Drum brake noise Brake induced fork judder 46 47 48 49 50 51 52 53 54 problems Battery dead or weak Battery overcharged Circuit failure 26 44 45 Brake problems Electrical 24 25 Gear lever does not return 40 41 Total electrical failure Gear 38 39 Handlebar vibrates or oscillates Poor front fork performance Front end noise 16 17 18 Firing incorrect Clutch slip Clutch drag left Abnormal frame and suspension noise high speeds Overheating Miscellaneous causes Steering bias to 1 Knocking or pinging General causes 36 37 1 Compression low Compression low Exhaust smokes excessively White/blue smoke (caused by oil burning) Black smoke (caused by over-rich mixture) stalls after starting at idle and low Weak spark at plug or erratic firing Fuel/air mixture incorrect 34 35 9 Compression low Poor running 30 Piston slap or rattling from cylinder Engine does not start when turned over No fuel flow to carburetor Engine 27 28 29 Bulbs blowing repeatedly 55 56 57 58 59 Troubleshooting 1 17 4 Starter motor and clutch function but engine will not turn over Introduction This Section provides an easy reference-guide to the more common your machine. Obviously, the opportuni- faults that are likely to afflict almost limitless for faults to occur as a result of obscure failures, and to try and cover all eventualities would require a book Indeed, a number have been written on the subject. Successful fault diagnosis is not a mysterious black art' but the application of a bit of knowledge combined with a systematic and logical approach to the problem Approach any fault diagnosis by first accurately identifying the symptom and then checking through the list of possible causes, starting with the simplest or most obvious and progressing in stages to the most complex. Take nothing for granted, but above all apply liberal quantities of common sense. The mam symptom of a fault is given in the text as a major heading below which are listed, as Section headings, the various systems or areas which may contain the fault. Details of each possible cause for a fault and the remedial action to be taken are given, in brief, in the paragraphs below each Section heading. Further information should be sought in the relevant Chapter. ties are • to Engine seized. Seizure of the engine components due internal to is always lubrication damage component a result of failure, or breakage resulting from abuse, neglect or old age. A seizing or partially component may go un noticed until the engine has cooled down and an attempt is made to restart the engine Suspect first seizure of the valves, valve gear and the pistons. Instantaneous seizure whilst the engine is running indicates component breakage In either case major dismantling and inspection will be required seized Engine does not start when turned over 5 • • • No No fuel flow to carburetor fuel or insufficient fuel in tank. Fuel tap lever position incorrectly selected. Tank filler cap air vent or breather pipe (California model) obstructed. Usually caused by dirt or water. Clean the vent orifice. Fuel tap or filter blocked. Blockage may be due to accumulation of rust or paint flakes from the tank's inner surface or of foreign matter • Starter 2 • • from contaminated fuel Remove the tap and clean it and the Look also for water droplets in the fuel • Fuel line blocked. Blockage of the fuel line is more likely to from a kink in the line rather than the accumulation of debris. motor problems Starter 6 motor not rotating Engine stop switch off. Fuse blown. Check the main fuse located behind the battery side cover. • Battery voltage low. Switching on the headlamp and operating the horn will give a good indication of the charge level. If necessary recharge the battery from an external source. • Neutral gear not selected • Faulty neutral indicator switch or clutch interlock switch. Check the switch wiring and switches for correct operation • Ignition switch defective Check switch for continuity and connections for security. • Engine stop switch defective Check switch for continuity in Run' position Fault will be caused by broken, wet or corroded switch contacts. Clean or renew as necessary. • for • Starter button switch faulty. Check continuity of switch Faults as engine stop switch. If the switch is functioning correctly should be heard when the starter button is depressed This presupposes that current is flowing to the solenoid when the button is depressed. • Wiring open or shorted Check first that the battery terminal connections are tight and corrosion free. Follow this by checking that all wiring connections are dry, tight and corrosion free. Check also for frayed or broken wiring. Occasionally a wire may become trapped a Starter relay (solenoid) faulty. pronounced click between two moving components, particularly in the vicinity of the steering head, leading to breakage of the internal core but leaving the softer but more resilient outer intermittent or total power cover intact. This can cause mysterious loss • Starter motor defective. A badly worn starter motor may cause high current drain from a battery without the motor rotating. If current IS found to be reaching the motor, after checking the starter button and starter relay, suspect a damaged motor. The motor should be removed for inspection. 3 • motor Float bowl not filling. Caused by may occur position. This after the float needle or floats sticking in left standing machine has been an extended length of time allowing the fuel to evaporate. When occurs a gummy residue is often left which hardens to a varnish-like substance This condition may be worsened by corrosion and crystaline deposits produced prior to the total evaporation of contaminated fuel. Sticking of the float needle may also be caused by wear. In any case removal of the float bowl will be necessary for this inspection and cleaning. • Blockage in starting circuit, slow running circuit or jets. Blockage these items may be attributable to debris from the fuel tank by-passing the filter system or to gumming up as described in paragraph 1 Water droplets in the fuel will also block jets and passages. The carburetor should be dismantled for cleaning. of • Fuel level too low. The The fuel level in the float bowl is controlled by may increase with wear or damage but will never reduce, thus a low float height is an inherent rather than developing condition Check the float height and make any necessary float height. float height adjustment. 7 Engine flooding • Float valve needle worn or stuck open. A piece of rust or other debris can prevent correct seating of the needle against the valve seat thereby permitting an uncontrolled flow of fuel. Similarly, a worn needle or needle seat will prevent valve closure. Dismantle the carburetor float bowl for cleaning and, if necessary, renewal of the worn components • Fuel level too high. The fuel level is controlled by the float height which may increase due to wear of the float needle, pivot pin or operating tang. Check the float height, and make any necessary adjustment. A leaking float will cause an increase in fuel level, and thus • Accelerator pump. On those models so equipped, repeated operation of the throttle prior to starting will cause flooding due to too much raw fuel being injected into the venturi. • clutch defective. Suspect jammed or worn plungers and springs. starter motor drive train. Inspect and renew component rollers, Damaged Fuel not reaching cylinder for Cold starting mechanism. Check the choke (starter mechanism) If the mechanism jams in the 'On' position subsequent starting of a hot engine will be difficult • Blocked air cleaner A badly restricted air cleaner will cause for Starter result should be renewed. Starter motor rotates but engine does not turn over engagement • • up filter. where necessary. Failure in this area is unlikely. correct operation flooding Check the filter and clean or renew as required. inlet adaptor will have a similar effect. A collapsed . 18 8 • • • • Troubleshooting No spark invariably at plug Ignition switch not on. Engine stop switch off. Fuse blown. Check fuse Battery voltage low. guide Chapter the spark plug shorts internally or has sustained visible damage to the electrodes, core or ceramic insulator it should be renewed. On rare occasions a plug that appears to spark vigorously will in 1 If to do so when refitted to the engine and subjected to the compression pressure in the cylinder. • Spark plug cap or high tension (HT) lead faulty Check condition and security Replace if deterioration is evident. • Spark plug cap loose Check that the spark plug cap fits securely over the plug and, where fitted, the screwed terminal on the plug end is fail secure. • Shorting due to moisture Certain parts of the ignition system are susceptible to shorting when the machine is ridden or parked in wet weather. Check particularly the area from the spark plug cap back to the ignition coil. A water dispersant spray may be used to dry out waterlogged components. Recurrence of the problem can be prevented by using an ignition sealant spray after drying out and cleaning. • Ignition or stop switch shorted. May be caused by water, corrosion or wear. Water dispersant and contact cleaning sprays may be used. If this fails to overcome the problem dismantling and visual inspection of the switches will be required. • Shorting or open circuit in wiring. Failure in any wire connecting any of the ignition components will cause ignition malfunction. Check also that all connections are clean, dry and tight. • Ignition coil failure. Check the coil, referring to Chapter 4. • Faulty CDI system component. Refer to Chapter 4. Weak spark at plug • Feeble sparking at the plug may be caused by any of the faults in the preceding Section other than those items in paragraphs 1 to 3. Check first the spark plug, this being the most likely culprit. 10 Compression low This will be self-evident on inspection, and may hissing noise when the engine is turned over. check that the threads in the cylinder head are also that the plug sealing washer is in good condition. • Cylinder head gasket leaking. This condition is often accompanied squeak from around the cylinder head and oil loss, and may be caused by insufficiently tightened cylinder head fasteners, a warped cylinder head or mechanical failure of the gasket material. Re-torqueing the fasteners to the correct specification may seal the leak in some instances but if damage has occurred this course of action will provide, at best, only a temporary cure. • Valve not seating correctly. The failure of a valve to seat may be caused by insufficient valve clearance, pitting of the valve seat or face, carbon deposits on the valve seat or seizure of the valve stem or valve gear components. Valve spring breakage will also prevent correct valve closure. The valve clearances should be checked first and then, if these are found to be in order, further dismantling will be required to inspect the relevant components for failure. • Cylinder, piston and ring wear. Compression pressure will be lost if any of these components are badly worn. Wear in one component is by a high pitched in A another top end overhaul will be • Piston rings sticking or broken. Sticking of the piston rings may be caused by seizure due to lack of lubrication or heating as a result of poor carburation or incorrect fuel type. Gumming of the rings may result from lack of use, or carbon deposits in the ring grooves. Broken rings result from over-revving, overheating or general wear In either case a top-end overhaul will be required. Engine 11 • stalls after starting General causes start mechanism operation. Check that the function smoothly and, where applicable, are correctly adjusted. A cold engine may not require application of an enriched mixture to start initially but may baulk without choke once firing. Likewise a hot engine may start with an enriched mixture but will stop almost immediately if the choke is inadvertently in operation. • Ignition malfunction See Section 9, Weak spark at plug'. • Carburetor incorrectly adjusted. Maladjustment of the mixture strength or idle speed may cause the engine to stop immediately after Improper operating starting. • cold controls See Chapter 3. Check for blockage by debris or water which reduces, but does not completely stop, fuel flow or blockage of the slow speed circuit in the carburetor by the same agents. If water is present it can often be seen as droplets in the bottom of the float bowl. Clean the filter and, where water is in evidence, dram and flush the fuel Fuel contamination. tank and float bowl. • Intake air leak. Check for security of the carburetor mounting and hose connections, and for cracks or splits in the hoses. Check also that the carburetor top is secure. • Air filter blocked or omitted. A blocked filter will cause an over-rich mixture; the omission of a filter will cause an excessively weak mixture. Both conditions will have a detrimental effect on carburation. Clean or renew the filter as necessary. • Fuel filler cap air vent or breather pipe (California model) blocked. Usually caused by dirt or water. Clean the vent orifice. Poor running at 12 mentioned • Spark plug loose. be accompanied by a Remove the plug and not damaged. Check accompanied by wear required. for ignition circuit. See wiring diagram. The current draw required by a starter motor is sufficiently high that an under-charged battery may not have enough spare capacity to provide power for the ignition circuit during starting. Recharge the battery. • Starter motor inefficient. A starter motor with worn brushes and a worn or dirty commutator will draw excessive amounts of current causing power starvation in the ignition system. See the preceding paragraph. Starter motor overhaul will be required. • Spark plug failure. Clean the spark plug thoroughly and reset the electrode gap. Refer to the spark plug section and the colour condition 9 . • Weak idle and low speed spark at plug or erratic firing In certain conditions low battery charge, with a badly sulphated battery, may result in misfiring. If the battery is in good general condition it should be recharged; an old battery suffering from sulphated plates should be Battery voltage low. especially when coupled renewed. • Spark plug fouled, faulty or incorrectly adjusted. See Section 8 or refer to Chapter 1 • Spark plug cap or high tension lead shorting. Check the condition of both these items ensuring that they are in good condition and dry and that the cap is fitted correctly. • Spark plug type incorrect. Fit plug of correct type and heat range as given in Specifications. In certain conditions a plug of hotter or colder type may be required for normal running. • Ignition timing incorrect. Check the ignition timing, ensuring that the advance • is functioning correctly. Faulty ignition coil. Partial failure of the coil internal insulation will diminish the performance of the coil. No component must be fitted. • Faulty CDI system components. Refer repair is possible, a new to Chapter 4. 13 Fuel/air mixture incorrect • • Intake air leak. See Section 1 1 Mixture strength incorrect. Adjust slow running mixture strength using pilot adjustment screw. • Pilot jet or slow running circuit blocked. The carburetor should be removed and dismantled for thorough cleaning. Blow through all jets and air passages with compressed air to clear obstructions. 19 Troubleshooting • Air cleaner clogged or omitted. Clean or fit air cleaner element as also that the element and air filter cover are correctly Check necessary. Knocking or pinging seated. • Cold start mechanism in operation. Check that the choke has not been left on inadvertently and the operation is correct. Where applicable check the operating cable free play. • Fuel level too high or too low. Check the float height and adjust as necessary. See Section 7. • Fuel tank air vent or breather pipe (California model) obstructed. Obstruction usually caused by dirt or water. Clean vent orifice. • Valve clearance incorrect. Check, and if necessary, adjust, the clearances. 14 Compression low • See Section 1 0. 19 General causes • Carbon build-up in combustion chamber. After high mileages have been covered a large accumulation of carbon may occur. This may glow red hot and cause premature ignition of the fuel/air mixture, in advance of normal firing by the spark plug. Cylinder head removal will be required to allow inspection and cleaning. • Fuel incorrect. A low grade fuel, or one of poor quality may result in compression induced detonation of the fuel resulting in knocking and pinking noises. Old fuel can cause similar problems. • Spark plug heat range incorrect. Uncontrolled pre-ignition can result from the use of a spark plug the heat range of which is too hot. • Weak mixture. Overheating of the engine due to a weak mixture can result in pre-ignition occurring where it would not occur when engine temperature was within normal limits. Maladjustment, blocked jets or passages and air leaks can cause this condition. Acceleration poor 15 General causes • • Overheating items as for previous Section. Accelerator pump defective. Where so equipped, check that accelerator pump injects raw fuel into the carburettor venturi, when throttle is open fully. If this does not occur check the condition of pump components and that the feed passage to the pump is obstructed. All • Brakes binding. Usually seizure of the operating caused by mechanism due maladjustment or the the not partial Check warped to poor maintenance. brake adjustment (where applicable). A bent wheel spindle or brake disc can produce similar symptoms. Poor running or lack of power at high speeds 16 Weak # • spark at plug or erratic firing items as for Section 12. lead insulation failure. Insulation failure of the HT lead and spark plug cap due to old age or damage can cause shorting when the engine is driven hard. This condition may be less noticeable, or not All HT noticeable at all at lower engine speeds. 17 Fuel/air mixture incorrect • • 20 Firing incorrect the items as for Section 13, with the exception of items 2 and 3. Main jet blocked. Debris from contaminated fuel, or from the fuel tank, and water in the fuel can block the mam jet. Clean the fuel filter, the float bowl area, and if water is present, flush and refill the fuel tank. • Main jet is the wrong size. The standard carburetor jetting is for sea level atmospheric pressure. For high altitudes a smaller main jet • • Spark plug fouled, defective or maladjusted. See Section 8. Spark plug type incorrect. Refer to the Specifications and ensure that the correct plug type is fitted. • Incorrect ignition timing. Timing that is far too much advanced or far too much retarded will cause overheating. Check the ignition timing is 21 • • correct. Fuel/air mixture incorrect Slow speed mixture strength incorrect. Main jet wrong size. The carburetor is jetted for sea level atmospheric conditions. • Air filter badly fitted or omitted. Check that the filter element is in place and that it and the air filter box cover are sealing correctly. Any leaks will cause a weak mixture. • Induction air leaks. Check the security of the carburetor mountings and hose connections, and for cracks and splits in the hoses. Check also that the carburetor top is secure. • Fuel gauge too low. See Section 6. • Fuel tank filler cap air vent or breather pipe (California model) obstructed. Clear blockage. All may be required • Jet needle and needle jet worn. These can be renewed individually but should be renewed as a pair. Renewal of both items requires partial dismantling of the carburetor • Air bleed holes blocked. Dismantle carburetor and use compressed air to blow out all air passages. • Reduced fuel flow. A reduction in the maximum fuel flow from the fuel tank to the carburetor will cause fuel starvation, proportionate to the engine speed. Check for blockages through debris or a kinked fuel 22 Lubrication inadequate • Engine oil too low. Not only does the oil serve as a lubricant by preventing friction between moving components, but it also acts as a coolant. Check the oil level and replenish. • Engine oil overworked. The lubricating properties of oil are lost slowly during use as a result of changes resulting from heat and also contamination. Always change the oil at the recommended interval. • Engine oil of incorrect viscosity or poor quality Always use the recommended viscosity and type of oil. line. 23 Miscellaneous causes 18 Compression low • See Section 1 0. • Engine fins clogged. A build-up of mud in the cylinder head and cylinder barrel cooling fins will decrease the cooling capabilities of the fins. Clean the fins as required. . . 20 Troubleshooting Clutch operating problems 24 Clutch • No • • slip clutch lever play. Adjust clutch lever end play according to the procedure • 27 Gear shift difficult or impossible Chapter in 1 worn or warped. Overhaul clutch assembly, replacing plates out of specification (Chapter 2). Steel plates worn or warped. Overhaul clutch assembly, replacing plates out of specification (Chapter 2). plates Friction • • Clutch springs broken or worn. Old or heat-damaged (from new ones (Chapter slipping clutch) springs should be replaced with 2). • Clutch release not adjusted properly. See the adjustments section of Chapter 1 • Clutch inner cable snagging. Caused by a frayed cable or kinked outer cable. Replace the cable with a new one. Repair of a frayed cable is not advised. • Clutch release mechanism defective. Worn or damaged parts in the clutch release mechanism could include the shaft, cam, actuating arm or pivot. Replace parts as necessary (Chapter 2). • Clutch center and outer drum worn. Severe indentation by the clutch plate tangs of the channels in the center and drum will cause snagging of the plates preventing correct engagement. If this damage occurs, renewal of the worn components is required • Lubricant incorrect. Use of a transmission lubricant other than that specified may allow the plates to slip. • Clutch lever play excessive. Adjust lever at bars or at cable end if necessary (Chapter 1 ). • Clutch plates warped or damaged. This will cause a drag on the clutch, causing the machine to creep. Overhaul clutch assembly (Chapter 2). • Clutch spring tension uneven. Usually caused by a sagged or broken spring. Check and replace springs (Chapter 2). • Engine oil deteriorated. Badly contaminated engine oil and a heavy deposit of oil sludge and carbon on the plates will cause plate sticking. The oil recommended for this machine is of the detergent type, therefore it is unlikely that this problem will arise unless regular • changes are neglected. Engine oil viscosity too high. Drag in the plates will result from the use of an oil with too high a viscosity. In very cold weather clutch drag may occur until the engine has reached operating temperature. • Clutch center and outer drum worn. Indentation by the clutch plate tangs of the channels in the center and drum will prevent easy plate disengagement. If the damage is light the affected areas may be dressed with a fine file. More pronounced damage will necessitate renewal of the components. • Clutch outer drum seized to shaft Lack of lubrication, severe wear or damage can cause the housing to seize to the shaft. Overhaul of the clutch, and perhaps the transmission, may be necessary to repair damage (Chapter 2). • Clutch release mechanism defective. Worn or damaged release mechanism parts can stick and fail to provide leverage. Overhaul clutch cover components (Chapter 2). • Loose clutch center nut. Causes drum and center misalignment, putting a drag on the engine. Engagement adjustment continually varies. Overhaul clutch assembly (Chapter 2). Gear shift problems Weak or broken centraliser spring. if the machine linkage. Provided that permissible. Structural failure. Failure of any and shift mechanism will one component result in of the selector improper or fouled gear selection. damage • Detent arm assembly worn or damaged. Wear of the arm and the it locates and breakage of the detent spring can cause imprecise gear selection resulting in jumping out of gear. Renew the cam with which damaged components. • Gear pinion dogs worn or damaged. Rounding off the dog edges and the mating recesses in adjacent pinion can lead to jumping out of gear when under load. The gears should be inspected and renewed. Attempting to reprofile the dogs is not recommended. • Selector forks, gearshift drum and pinion grooves worn. Extreme wear of these interconnected items can occur after high mileages especially when lubrication has been neglected. The worn components must be renewed. • Gear pinions, bushes and shafts worn. Renew the worn components. • Bent gearshift shaft. Often caused by dropping the machine on the gear lever linkage. • Gear pinion tooth broken. Chipped teeth are unlikely to cause jumping out of gear once the gear has been selected fully; a tooth which IS completely broken off, however, may cause problems in this respect and in any event will cause transmission noise. 29 Overselection • • • Pawl spring weak or broken. Renew the spring. Detent arm worn or broken. Renew the damaged items. Stopper arm spring worn or broken. Renew the spring. Abnormal engine • Renew the spring. Gearshift shaft bent or seized. Distortion of the gearshift shaft often occurs • shaft noise. 30 Knocking or pinging 26 Gear lever does not return • • required. 28 Jumping out of gear 25 Clutch drag oil Clutch not disengaging fully. See Section 25 Gearshift shaft bent This often occurs if the machine is dropped heavily on the gear lever linkage. Straightening of the shaft is permissible if the damage is not too great. • Gearshift arms or pins worn or damaged. Wear or breakage of any of these items may cause difficulty in selecting one or more gears. Overhaul the shifter mechanism. • Gearshift shaft centraliser spring maladjusted. This is often characterised by difficulties in changing up or down, but rarely in both directions. Adjust the centraliser anchor bolt as described in Chapter 2. • Gearshift arm spring broken. Renew spring. • Selector drum stopper cam or detent arm damage. Failure, rather than we3r, of these items may jam the drum thereby preventing gearshifting. The damaged items must be renewed. • Selector forks bent or seized. This can be caused by dropping the machine heavily on the gearchange lever linkage or as a result of lack of lubrication. Though rare, bending of a shaft can result from a missed gear or false selection at high speed. • Selector fork end and pin wear Pronounced wear of these items and the grooves in the selector drum can lead to imprecise selection and, eventually, no selection. Renewal of the worn components will be is is dropped heavily on the gear lever not severe straightening of the shaft is 31 • See Section 1 9. Piston slap or rattling from cylinder Cylinder bore/piston clearance excessive Resulting from wear, improper boring during overhaul. This condition can partial seizure or Troubleshooting when the engine is under no load, particularly when power is just beginning to be applied. Reboring to the next correct oversize should be carried out and a new oversize piston fitted. • Connecting rod bent. This can be caused by over-revving, trying to start a very badly flooded engine (resulting in a hydraulic lock in the cylinder) or by earlier mechanical failure such as a dropped valve. Attempts at straightening a bent connecting rod are not recommended. Careful inspection of the crankshaft should be made before renewing often be heard as a high, rapid tapping noise or little the • damaged connecting rod. Piston pin, piston boss bore or small end wear or seizure. Excess clearance or partial seizure between normal moving parts' of these items can cause continuous or intermittent tapping noises Rapid wear seizure is caused by lubrication starvation resulting from an insufficient engine oil level or oilway blockage. or • Piston rings worn, broken or sticking. Renew the rings after 21 temporary The gasket should cure clamp should be looked • • Valve spring broken or weak. Renew the spring set. Camshaft or cylinder head worn or damaged. The camshaft lobes are the most highly stressed of all components in the engine and are subject to high wear if lubrication becomes inadequate. The bearing surfaces on the camshaft and cylinder head are also sensitive to a lack of lubrication. Lubrication failure due to blocked oilways can occur, but over-enthusiastic revving before engine warm-up is complete is the usual cause. • Rocker arm or spindle wear Rapid wear of a rocker arm, and the need for frequent valve clearance adjustment, indicates breakthrough or failure of the surface hardening on the rocker arm tips. Similar wear in the cam lobes can be expected Renew the worn components after checking for lubrication failure • Worn camshaft drive components. A rustling noise or light tapping which IS not improved by correct re-adjustment of the cam chain tension can be emitted by a worn cam chain or worn sprockets and chain. If uncorrected, subsequent cam chain breakage may cause extensive damage. The worn components must be renewed before wear becomes too far advanced. resulting 33 Other noises crankshaft. • Crankshaft excessively out of true. A bent crank may result from over-revving or damage from an upper cylinder component or gearbox Damage can also result from dropping the machine on either crankshaft end. Straightening of the crankshaft is not possible in normal circumstances; a replacement item should be fitted. failure. Engine mounting loose. Tighten • Clutch outer drum/friction plate tang clearance excessive. Clutch outer drum/outer guide clearance excessive. Clutch outer drum/thrust washer clearance excessive. Primary drive gear teeth worn or damaged. Bearing bushings worn or damaged. or Renew the affected components • • Gear pinions worn or chipped. Renew the gear pinions. Metal chips jammed in gear teeth. This can occur when pieces of metal from any failed component are picked up by a meshing pinion. The condition will lead to rapid bearing wear or early gear failure. Engine/transmission oil level too low. Top up immediately to prevent damage to gearbox and engine. • • Gearshift items in or damaged Wear or failure of certain components can induce mis-selection Section 27) where incipient engagement of more than mechanism worn the selection and shift of gears (see one gear set is promoted. Remedial action, by the overhaul of the gearbox, should be taken without delay. • Loose gearbox chain sprocket. Remove the sprocket and check for impact damage to the splines of the sprocket and shaft. Excessive slack between the splines will promote loosening of the securing bolts; renewal of the worn components is required. When retightening the nut ensure that it is tightened fully and that, where fitted, the lock washer is bent up against one flat of the nut. • Cham snagging on cases or cycle parts. A badly worn chain or one that IS excessively loose may snag or smack against adjacent components. • Big end bearing wear. A pronounced knock from within the crankcase which worsens rapidly is indicative of big end bearing failure as a result of extreme normal wear or lubrication failure. Remedial action in the form of a bottom end overhaul should be taken; continuing to run the engine will lead to further damage including the possibility of connecting rod breakage. • Main bearing failure. Extreme normal wear or failure of the main bearings is characteristically accompanied by a rumble from the crankcase and vibration felt through the frame and footrests. Renew the worn bearings and carry out a very careful examination of the • earliest 34 Clutch noise 35 Transmission noise Valve clearance incorrect. Adjust the clearances with the engine the Abnormal transmission noise • cold. at for. 32 Valve noise or tapping from the cylinder head and bore. renewed • Exhaust system leakage. Popping or crackling in the exhaust system, particularly when it occurs with the engine on the overrun, indicates a poor joint either at the cylinder port or at the exhaust pipe/silencer connection Failure of the gasket or looseness of the # # • • careful inspection of the piston be opportunity. all the engine mounting nuts and bolts. • Cylinder head gasket leaking. The noise most often associated with a leaking head gasket is a high pitched squeaking, although any other noise consistent with gas being forced out under pressure from a small orifice can also be emitted. Gasket leakage is often accompanied by oil seepage from around the mating joint or from the cylinder head holding down bolts and nuts. Leakage into the cam chain tunnel or oil return passages will increase crankcase pressure and may cause oil leakage at joints and oil seals. Also, oil contamination will be accelerated Leakage results from insufficient or uneven tightening of the cylinder head fasteners, or from random mechanical failure. Retightening to the correct torque figure will, at best, only provide a Exhaust smokes excessively 36 White/blue smoke (caused by • worn Piston rings particularly the oil or broken oil burning) Breakage or wear of any control ring, will allow engine oil ring, but past the piston into the combustion chamber. Overhaul the cylinder barrel and piston. Cylinder cracked, worn or scored These conditions may • be caused by overheating, lack of lubrication, component failure or advanced normal wear. The cylinder barrel should be renewed or rebored and the next oversize piston fitted. • Valve oil seal damaged or worn. This can occur as a result of valve guide failure or old age. The emission of smoke is likely to occur when the throttle is closed rapidly after acceleration, for instance, when oil seals and, if necessary, the valve changing gear Renew the valve guides. • • Valve guides worn. See the preceding paragraph. Engine oil level too high. This increases the crankcase pressure and allows oil to be forced past the piston rings. Often accompanied by seepage of • oil at joints and oil seals. Cylinder head gasket blown between cam chain tunnel or return passage. Renew the cylinder head gasket. oil • Abnormal crankcase pressure. This may be caused by blocked breather passages or hoses causing back-pressure at high engine revolutions. Troubleshooting 22 smoke (caused by 37 Black • • Air filter over-rich mixture) element clogged Clean or renew the element loose or too large. Remove the float chamber to check for tightness of the jet. If the machine is used at high altitudes rejetting will be required to compensate for the lower atmospheric pressure. Main jet • Cold start mechanism jammed on Check that the mechanism works smoothly and correctly and that, where fitted, the operating cable is lubricated and not snagged • Fuel level too high. The fuel level is controlled by the float height which can increase as a result of wear or damage. Remove the float bowl and check the float height. Check also that floats have not punctured; a punctured float will loose buoyancy and allow an increased fuel • float chamber or Caused by dirt renew the needle and, or a if worn valve. necessary, the valve seat. Poor handling or roadholding 38 Directional instability • or • Steering head bearing adjustment too tight. This will cause rolling at low speeds. Re-adjust the bearings. Steering head bearing worn or damaged. Correct adjustment of weaving the bearing will prove impossible to achieve if wear or damage has occurred. Inconsistent handling will occur including rolling or weaving at low speed and poor directional control at indeterminate higher speeds. The steering head bearing should be dismantled for inspection and renewed if required. Lubrication should also be carried out. • Bearing races pitted or dented. Impact damage caused, perhaps, by an accident or riding over a pot-hole can cause indentation of the bearing, usually in one position. This should be noted as notchiness when the handlebars are turned Renew and lubricate the bearings. • Steering stem bent. This will occur only if the machine is subjected to a high impact such as hitting a curb or a pot-hole. The lower triple clamp/stem should be renewed; do not attempt to straighten the stem. • Front or rear tire pressures too low. • Front or rear tire worn. General instability, high speed wobbles and skipping over white lines indicates that tire renewal may be required. Tire induced problems, in some machine/tire combinations, can occur even when the tire in question is by no means fully worn. • Swingarm bearings worn. Difficulty in holding tine, particularly when cornering or when changing power settings indicates wear in the swingarm bearings. The swingarm should be removed from the machine and the bearings renewed. • Swingarm flexing. The symptoms given in the preceding paragraph will also occur if the swingarm fork flexes badly. This can be caused by structural weakness as a result of corrosion, fatigue or impact damage, or because the rear wheel spindle is slack. • Wheel bearings worn. Renew the worn bearings. • Loose wheel spokes. The spokes should be tightened evenly to maintain tension and trueness of the rim. • Tires unsuitable for machine. Not all available tires will suit the characteristics of the frame and suspension, indeed, some tires or tire combinations may cause a transformation in the handling characteristics. If handling problems occur immediately after changing to a new tire type or make, revert to the original tires to see whether an improvement can be noted. In some instances a change to what are, in fact, suitable tires may give rise to handling deficiences. In this case a thorough check should be made which affect stability. 39 Steering bias to of all frame and suspension items left or right • Rear wheel out of alignment. Caused by uneven adjustment of chain tensioner adjusters allowing the wheel to be askew in the fork ends. A bent rear wheel spindle will also misalign the wheel in the swingarm. • the Wheels out frame, steering triple clamps without causing structural damage to the fork clamps themselves. Re-alignment can be made by loosening the triple clamp pinch bolts, wheel spindle and mudguard bolts Re align the wheel with the handlebars and tighten the bolts working upwards from the wheel spindle This action should be carried out only when there is no chance that structural damage has occurred. legs or the triple 40 Handlebar vibrates or oscillates level. Float valve needle stuck open. Clean the occasionally a result of material failure or corrosion it is usually as a an accident. • Front forks twisted in the steering triple clamps. A light impact, for instance with a pot-hole or low curb, can twist the fork legs m the result of of alignment. This swingarm, wheel can be caused by impact damage to or front forks. Although spindles • Tires^worn or out of balance. Either condition, particularly in the tire, will promote shaking of the fork assembly and thus the handlebars. A sudden onset of shaking can result if a balance weight is displaced during use. • Tires badly positioned on the wheel rims. A moulded line on each wall of a tire is provided to allow visual verification that the tire is correctly positioned on the rim A check can be made by rotating the tire; any misalignment will be immediately obvious. • Wheel rims warped or damaged. Inspect the wheels for runout as described in Chapter 6. • Swingarm bearings worn. Renew the bearings. • Wheel bearings worn. Renew the bearings. • Steering head bearings incorrectly adjusted. Vibration is more likely to result from bearings which are too loose rather than too tight. Re-adjust the bearings. • Loose fork component fasteners. Loose nuts and bolts holding the fork legs, wheel spindle, mudguards or steering stem can promote shaking at the handlebars Fasteners on running gear such as the forks and suspension should be check tightened occasionally to prevent dangerous looseness of components occurring. • Engine mounting bolts loose. Tighten all fasteners. front 41 Poor front fork performance • Damping fluid level incorrect. If the fluid level is too low poor suspension control will occur resulting in a general impairment of roadholding and early loss of tire adhesion when cornering and Too much oil is unlikely to change the fork characteristics unless severe overfilling occurs when the fork action will become stiffer and oil seal failure may occur. braking. • Damping oil viscosity incorrect. The damping action of the fork is damping oil. The lighter the oil directly related to the viscosity of the used, the less will be the damping action imparted. For general use, use the recommended viscosity of oil, changing to a slightly higher or heavier oil only when a change in damping characteristic is required. contaminated with water which has found its way past the seals, should be renewed to restore the correct damping performance and to prevent bottoming of the forks. • Damping components worn or corroded. Advanced normal wear of the fork internals is unlikely to ocur until a very high mileage has been covered. Continual use of the machine with damaged oil seals Overworked oil, or oil which allows the ingress of water, or neglect, will lead to rapid corrosion and wear. Dismantle the forks for inspection and overhaul. See Chapter • Weak 5. fork springs. Progressive fatigue of the fork springs, resulting in a reduced spring free length, will occur after extensive use. This condition will promote excessive fork dive under braking, and in its advanced form will reduce the at-rest extended length of the forks and thus the fork geometry. Renewal of the springs as a pair is the only satisfactory course of action. • Bent or corroded fork tubes. Both conditions will prevent correct telescoping of the fork legs, and in an advanced state can cause sticking of the fork in one position. In a mild form corrosion will cause stiction of the fork thereby increasing the time the suspension takes to react to an uneven road surface. Bent fork tubes should be attended to immediately because they indicate that impact damage has occurred, and there is a danger that the forks will fail with disastrous consequences. Troubleshooting 42 Front fork judder • when internal parts will prevent pressurisation of the brake fluid. braking (see also Section 54) Wear between the fork tubes and the components is required. fork sliders. Renewal of the affected • • Slack steering head bearings. Re-adjust the bearings. Warped brake disc. If irregular braking action occurs fork judder can be induced in what are normally serviceable forks. Renew the damaged brake components. • Rear suspension unit damper worn out or leaking. The damping performance of most rear suspension units falls off with age. This is a gradual process, and thus may not be immediately obvious. Indications of poor damping include hopping of the rear end when cornering or braking, and a general loss of positive stability. See Chapter 5 • Weak rear springs. If the suspension unit springs fatigue they will promote excessive pitching of the machine and reduce the ground clearance when cornering. Although replacement springs are available separately from the rear suspension damper unit it is probable that if spring fatigue has occurred the damper units will also require renewal. • Swingarm flexing or bearings worn. See Sections 38 and 39. • Bent suspension unit damper rod. This is likely to occur only if the machine is dropped or if seizure of the piston occurs. renewed as If either happens a pair. Abnormal frame and suspension noise 44 Front end noise • • contamination of the brake pads and assembly. low or too thin. This can cause a accompanied by irregular fork action. spurting' sound and is weak or broken. Makes a clicking or scraping sound. Fork have a lot of metal particles in it. • Steering head bearings loose or damaged. Clicks when braking. Check, adjust or replace. • Fork triple clamps loose. Make sure all fork clamp pinch bolts are Spring oil will caliper. Overhaul the caliper 47 Brakes drag - disc brakes Disc warped. The disc must be renewed. piston, caliper or pads corroded. The brake caliper assembly is vulnerable to corrosion due to water and dirt, and unless cleaned at regular intervals and lubricated in the recommended Caliper manner, • will become sticky in operation. The seal is designed to return the piston the caliper to the retracted position when the brake is released. Wear or old age can affect this function. The caliper should be overhauled if Piston seal deteriorated. in this occurs. • Brake pad damaged. Pad material separating from the backing due to wear or faulty manufacture. Renew the pads. Faulty installation of a pad also will cause dragging. • Wheel spindle bent. The spindle may be straightened if no structural damage has occurred. • Brake lever not returning. Check that the lever or pedal works smoothly throughout its operating range and does not snag on any adjacent cycle parts. Lubricate the pivot if necessary. • Twisted caliper support bracket. This is likely to occur only after impact in an accident. No attempt should be made to re-align the caliper; the bracket should be renewed. plate 48 Brake lever or pedal pulsates Oil level usually Overhaul the master cylinder unit. • Caliper seal failure. This will almost certainly be obvious by loss of fluid, a lowering of fluid in the master cylinder reservoir and • • 43 Poor rear suspension performance the suspension units should be 23 • • Disc warped Wheel axle in operation - disc brakes worn. The disc must be renewed. may be straightened provided no structural damage has occurred or irregularly bent. The axle 49 Disc brake noise tight. • Fork tube bent. Good possibility if machine has been dropped. Repair or replace tube. 45 Rear suspension noise • Fluid level too kDw. Leakage of a suspension unit, usually evident by oil on the outer surfaces, can cause a spurting noise The suspension units should be renewed as a pair. • Defective rear suspension unit with internal damage Renew the suspension units as a pair. Brake problems 46 Brakes are spongy or ineffective - disc brakes • Air in brake circuit. This is only likely to happen in service due to checking the fluid level or because a leak has developed. The problem should be identified and the brake system bled of air. • Pads worn. Check the pad wear against the wear lines provided and renew the pads if necessary. • Contaminated pads. Cleaning pads which have been contaminated with oil, grease or brake fluid is unlikely to prove successful; the pads should be renewed. • Pads glazed. This Is usually caused by overheating The surface of the pads may be roughened using glass-paper or a fine file. • Brake fluid deterioration. A brake which on initial operation is firm neglect • Brake squeal. This can be caused by dust on the pads, usually in combination with glazed pads, or other contamination from oil, grease, brake fluid or corrosion. Persistent squealing which cannot be traced to any of the normal causes can often be cured by applying a thin layer of high temperature silicone grease to the rear of the pads Make absolutely certain that no grease is allowed to contaminate the braking surface of the pads • Glazed pads. This is usually caused by high temperatures or contamination. The pad surfaces may be roughened using glass-paper or a fine file. If this approach does not effect a cure the pads should be renewed. • Disc warped This can cause a chattering, clicking or intermittent squeal and is usually accompanied by a pulsating brake lever or uneven braking. The disc must be renewed. • Brake pads fitted incorrectly or undersize. Longitudinal play in the pads due to omission of the locating springs (where fitted) or because pads of the wrong size have been fitted will cause a single tapping noise every time the brake is operated. Inspect the pads for correct installation and security. in but rapidly becomes spongy in use may be failing due to water contamination of the fluid. The fluid should be drained and then the system refilled and bled. • Master cylinder seal failure. Wear or damage of master cylinder 50 Brakes are spongy or ineffective - drum brakes • Worn brake linings. Determine lining wear using the external brake wear indicator on the brake backplate, or by removing the wheel and withdrawing the brake backplate Renew the shoe/lining units as a pair if the linings are worn below the recommended limit. • Worn brake cam. Wear between the cam and the bearing surface will reduce brake feel and reduce operating efficiency. Renewal of one or both items will be required to rectify the fault. • • Worn brake cam and shoe ends. Renew the worn components. Linings contaminated with dust or grease. Any accumulations of dust should be cleaned from the brake assembly and drum using a Troubleshooting 24 petrol dampened cloth. Do not blow or brush off the dust because it is asbestos based and thus harmful if inhaled. Light contamination from grease can be removed from the surface of the brake linings using a solvent; attempts at removmg heavier contamination are less likely to be successful because some of the lubricant will have been absorbed by the lining material which will severely reduce the braking performance. 51 • • Brake drag - drum brakes Incorrect adjustment. Re-adjust the brake operating Drum warped or oval. This can result mechanism. • • • Regulator/rectifier failure. AC generator coils open-circuit or shorted. Charging circuit shorting or open circuit. This may be caused by frayed or broken wiring, dirty connectors or a faulty ignition switch. The system should be tested in a logical manner. See Section 58 and Chapter 7. of the although if slight ovality only occurs, satisfactory solution. • which increase the total electrical load above the maximum AC generator output, the battery will fail to maintain full charge. Reduce the electrical load to suit the electrical capacity. from overheating, impact or wheel spokes. The condition is difficult to skimming the surface of the brake drum can provide a cure. This is work for a specialist engineer. Renewal of the complete wheel hub is normally the only uneven tension correct, clean them and the terminals, removing all traces of corrosion and tarnish. Reconnect the leads and apply a coating of petroleum jelly to the terminals • Load excessive If additional items such as spot lamps, are fitted, Weak brake shoe return springs. This will prevent the brake lining/shoe units from pulling away from the drum surface once the brake is released The springs should be renewed. • Brake cam, pedal pivot or linkage poorly lubricated. Failure to attend to regular lubrication of these areas will increase operating resistance which, when compounded, may cause tardy operation and poor release movement. 56 Battery overcharged • Rectifier/regulator faulty. Overcharging is indicated if the battery noticed that the electrolyte level falls repeatedly In extreme cases the battery will boil causing corrosive gases and electrolyte to be emitted through the vent pipes. • Battery wrongly matched to the electrical circuit. Ensure that the specified battery is fitted to the machine. becomes hot or between checks. is it 57 Total electrical failure 52 Brake lever or pedal pulsates • Drums warped operation - drum brakes from overheating, impact or uneven spoke tension. This condition is difficult to correct, although if slight ovality only occurs skimming the surface of the drum can provide or oval This can in result a cure. This is work for a specialist engineer. Renewal of the hub normally the only satisfactory solution. 53 Drum brake is file. 54 Brake induced fork judder Worn and sliders, or worn or badly adjusted These conditions, combined with uneven or pulsating braking as described in Sections 48 and 52 will induce more or less judder when the brakes are applied, dependent on the degree of wear and poor brake operation Attention should be given to both areas of malfunction. See the relevant Sections. front fork tubes steering head bearings. Electrical contact. • Ignition switch or power circuit failure. Check for current flow through the battery positive lead (red) to the ignition switch. Check the ignition switch for continuity. noise • Drum warped or oval. This can cause intermittent rubbing of the brake linings against the drum. See the preceding Section. • Brake linings glazed. This condition, usually accompanied by heavy lining dust contamination, often induces brake squeal. The surface of the linings may be roughened using glass-paper or a fine • • Fuse blown. Check the main fuse. If a fault has occurred, it must be rectified before a new fuse is fitted • Battery faulty. See Section 55. • Earth failure Check that the frame main earth (ground) strap from the battery is securely affixed to the frame and is making a good 58 Circuit failure • • been identified and rectified. Vibration failure. This often an inherent fault related to the and frame and is, thus, Modifications of the lamp mounting to change the may help • Intermittent earth (ground). Repeated failure of one bulb indicates that a poor earth exists somewhere in the circuit. Check that a good contact is available at each earthing point in the circuit • Reduced voltage. Where a quartz-halogen bulb is fitted the voltage to the bulb should be maintained or early failure of the bulb will occur. Do not overload the system with additional electrical equipment in excess of the system's power capacity and ensure that all circuit connections are maintained clean and tight. difficult to resolve. damping life is natural vibration characteristics of the engine weak Battery faulty. Battery Refer to the machine s wiring diagram and check the Open circuits are a result of loose or corroded connections, either at terminals or in-line connectors, or because of broken wires. Occasionally, the core of a wire will break without there being any apparent damage to the outer plastic cover. • Switch failure. All switches may be checked for continuity in each switch position, after referring to the switch position boxes incorporated in the wiring diagram for the machine. Switch failure may be a result of mechanical breakage, corrosion or water. • Fuse blown. Refer to the wiring diagram to check whether or not a circuit fuse is fitted. Replace the fuse, if blown, only after the fault has • should not be expected to exceed 3 to 4 where a starter motor is used regularly. Gradual sulphation of the plates and sediment deposits will reduce the battery performance. Plate and insulator damage can often occur as a result of vibration. Complete power failure, or intermittent failure, may be due to years, failure. 59 Bulbs blowing repeatedly problems 55 Battery dead or Cable circuit for continuity. particularly a broken battery terminal. Lack of electrolyte will prevent the battery maintaining charge. • Battery leads making poor contact. Remove the battery leads and characteristics 7 1 Chapter Tune-up and routine maintenance 1 Contents Routine maintenance intervals 2 3 Fuel line inspection 4 Cylinder compression check Evaporative emission control system - check (California models only) Drive chain - adjustment, cleaning and lubrication Cleaning the fuel strainer Throttle operation and free play - check, lubrication and adjustment Choke operation and free play - check, lubrication and adjustment 5 Battery - maintenance 6 Front brake hydraulic fluid tsvel - chsck Front brake - check Rear brake - check and 8d}Uitm#nt Introduction 1 Daily or pre-ride inspection Air filter and maintenance - servicing 7 8 9 10 Crankcase breather - servicing Spark plugs - renewal Valve clearances - check and adjustment Changing the engine oil Cleaning the oil filter screen Engine idle speed - check and adjustment Ignition timing - check 1 12 13 14 15 16 1 18 19 20 21 22 23 24 25 26 27 28 29 Headlight - check and adjultment Clutch - adjustment Side stand - inspection and pad renewal Suspension - check Nuts, bolts and fasteners - check Wheels and tirei - check and pressure adjustment Steering head bearings - check and adjustment Specifications Engine Recommended NGK spark plug: mm (0.024 - 0.028 in) 14 ± 2 kg/cm^ (199 ± 28 psi) oil: Capacity - at oil change Clutch lever free play - at lever end Throttle cable free play - at throttle grip flange Idle U20FSR-U U22FSR-U 0.6 - 0.7 Compression pressure Engine/transmission Capacity - dry ND CR6HS CR7HS Standard Extended high speed use Spark plug gap .... speed Valve clearance - intake and exhaust 1.8 liter (19 US qt) 1.5 liter (1.6 qt) US 10 - 20 mm (3/8 2 - 6 mm (Vs 1 300 ± 1 00 rpm 0.05 mm (0 002 3/4 in) in) in) Ignition timing: At At F' full mark advance 5° Frame and suspension Drive chain free play - at mid-point of lower run Front fork oil capacity Tire pressures (cold) Recommended BTDC at 1300 rpm BTDC at 3500 rpm 30° 15 - 25 mm (S/s - 1 in) 238 cc (8.1 US fl oz) 28 psi (2.0 kg/cm^') lubricants and fluids Engine/transmission oil: Type SE Viscosity SAE 10W/40 Brake fluid type Pedal/lever/stand pivots Cables Wheel and steering head bearings Drive chain Torque specifications Engine/transmission oil drain plug Cylinder head cover bolt Valve adjuster locknut Fuel petcock cup Brake pad pin bolt Rear axle nut or SF motor oil DOT 3 or 4 Lightweight grease, motor oil or dry-film lubricant Motor oil or cable lubricant Medium weight lithium-based grease SAE 80 Of go gear oil, or chain lubricant labelled as safe 0-ring chaiws Ft-lb m-Kg 22 - 29 3.0 - 4.0 0.8 - 1.2 6-9 6-9 2.2 - 3.6 10- 14 58 - 72 0.8 - 1.2 0.3 - 0.5 1.5 - 2 0 8.0 - 10.0 for use on Chapter 26 1 Tune-up and routine maintenance Introduction 1 3 Routine maintenance plays an important part in l 22 3 Adjust 1 Tune-up and routine maintenance 35 / rear brake to give prescribed pedal travel 22.4 Turning knurled adjuster sets brake switch position 23 Headlight - check and adjustment 24 Clutch - adjustment 1 Switch on the ignition and check that the headlight operates normally on both high and low beam positions. If there is a fault, refer to Chapter 7 for more information. 2 The headlight aim should be checked periodically, and the setting must comply with local regulations. A badly adjusted headlight will not illuminate the road properly, and may cause problems for oncoming Measure the amount of free play at the end of the clutch lever. The end should move ^/s - 3/4 in (10 - 20 mm) before the clutch mechanism is engaged. Minor adjustments can be carried out using the adjuster near the lever. Pull back the rubber boot and slacken the locknut. The adjuster can then be turned in or out to give the required amount of play. 2 If there is insufficient movement in the upper adjuster, screw it fully home to give maximum free play. Moving to the lower adjuster, slacken the locknut, then set the adjuster to give the required amount of free play at the clutch lever. Subsequent fine adjustment can now be drivers. is set by slackening the two bolts near the base and moving the unit up or down to the required position. Horizontal adjustment can be carried out after slackening the single nut on the underside of the lower triple clamp. 3 Vertical adjustment of the headlight, 1 lever undertaken using the upper adjuster When adjustment is complete, all locknuts and check that the clutch functions normally. tighten 23.1 Slacken bolts (arrowed) to seat headlight vertical aim 24.1 Use handlebar adjuster for fine setting of clutch lever Chapter 36 1 Tune-up and routine maintenance 25 Side stand - inspection and pad renewal The Honda Rebel models are equipped with a side stand only. To 1 check the stand and to permit pad renewal, the machine must be supported upright. This can be done using a workshop stand, or a similar arrangement can be improvised. We used some large wooden blocks beneath the frame tubes, then lashed the machine in position using tie-down straps. Whatever the method used, ensure that the machine is secure before starting work on the stand. 2 Inspect the stand for signs of wear or damage. Check that it moves smoothly and easily, but without excess free play at the pivot bolt. Check that the sprmg is undamaged and that it retracts the stand fully. Lubricate the stand pivot. Honda recommend that a force of 4.4 - 6.6 lb (2.0 - 3.0 kg) should be sufficient to retract the stand. This can be checked using a spring balance hooked to the end of the stand. 3 A rubber pad is fitted to the end of the stand. This is a safety device and is designed to retract the stand if the machine is ridden off with the stand down. If the pad is worn down It may result in the stand digging Into the road surface, which could flip the motorcycle onto its side. If the pad has worn down to the wear line at any point it must be renewed. It Is secured by a pressed steel holder and a single bolt. 26.2 If adjusting rear suspension, ensure both units are set to the position same preload 26 Suspension - check The suspension components should be examined damage, corrosion and excessive free play The front forks should be checked for scoring and oil leaks. Apply the front brake and pump the forks up and down several times. The forks should move smoothly and evenly with no sign of sticking or unusual noises. damaged In any way, refer to Chapter 5 for information on If 1 and front rear closely for signs of overhauling the forks. 2 Check the rear suspension units for smooth operation and signs of leakage. If damaged, the units must be renewed as a pair. Place a stand or wooden blocks under the engine to raise the rear wheel clear of the ground, making sure that the machine is securely lashed In place. Feel for free play In the swingarm bearings by pushing and pulling the assembly from side to side If movement can be felt, refer to Chapter 5 for details of overhauling the swingarm. 27 Nuts, bolts and fasteners - check The various fittings and fasteners should be checked for security, an operation which -can conveniently be combined with cleaning the machine Check that all hose and wiring guides are In position and secure. Check all cotter pins 28 1 Use an accurate pocket gauge instead of gas station item and R-pins. 28 Wheels and tires - check and tire pressure adjustment 1 Check the front and an accurate pressure must be cold when the check is made. rear tire pressures, using gauge, and noting that the tires The recommended pressures are given In the Specifications Section. Examine both tires closely for cuts, splits, nails or stones embedded 2 In the treads or other damage. Unless such damage is very minor, the should be renewed. Do not take any chances with tire condition - a blowout can be fatal to the rider or other road users. Check the depth of tire the tire tread. Renew the tire if worn to 0.06 in (T5 mm) in the case of the front, or 0.08 in (2.0 mm) in the case of the rear. 3 Check the wheel rims and spokes for damage. If the rim is buckled or dented, it should be renewed, as should any broken spokes. This is a should not be attempted at home. Honda spokes should be tightened periodically, and produce a special torque wrench for this purpose. If significant tightening is required to achieve the specified torque setting of 1 .8 3.6 ft-lb (0.25 - 0.50 kg-m), care should be taken that the spoke does not contact the tube. It is preferable to remove the tire to check this, and to allow any excess spoke to be filed flat. specialist job recommend and that the 28.2 Tread depth gauge permits accuracy tire wear to be assessed with Chapter 1 Tune-up and routine maintenance 28 Steering head bearings - check and adjustment 1 Use a stand or wooden blocks below the engine to raise the front wheel clear of the ground. Make sure that the machine is secure in this position. Check that the handlebar moves freely from lock to lock, with no sign of stiffness or roughness in the bearings. Any roughness in the bearing movement indicates 37 wear or damage in the bearings, and they should be dismantled for examination as described in Chapter 5. 2 Grasp the lower ends of the forks and attempt to push and pull them. If movement can be felt in the steering head bearings, or if the bearings felt stiff when the handlebar was turned, check and adjust the bearing clearance as described in Chapter 5. 4 8 1 Chapter 2 Engine and transmission Contents General information Major engine repair - general notes Repair operations requiring engine rennoval Engine - removal and installation Engine disassembly and reassembly - general note Camshaft and rockers - removal, inspection and 1 AC 3 and installation Crankcase - disassembly and reassembly Crankcase and bearings Selector forks and drum Transmission gears and shafts - disassembly, inspection and reassembly Cam chain and tensioner - removal, inspection and installation 4 5 6 installation Cylinder head - removal, inspection and installation Valves - disassembly, inspection and installation Cylinder block - removal and installation Pistons - removal, inspection and installation Clutch ~ removal, inspection and installation 1 and oil pump drive gear - removal, inspection and installation 12 Oil pump, primary Gearshift linkage - removal, inspection and installation generator and starter drive ~ removal, inspection 2 7 8 9 10 drive gear Displacement Compression ratio Compression pressure mm mm (2.1 in) (2.1 in) 234 cc (14.2 cu in) 9.2:1 14 ± 2 kg/cm^ (199 ± 28 psi) Camshaft and rocker arms Type Lobe height: Single overhead camshaft (sohc) 27.2 Exhaust Service limit Camshaft runout - maximum Bearing journal Service limit OD Camshaft bush ID Service limit Rocker arm ID Service limit Rocker shaft Service mm (1 0801 in) mm (1.07 in) 27.263 mm (1.0733 in) 27.0 mm (1 .06 in) 0.05 mm (0.002 in) 19.967 - 19.980 mm (0.7861 - 0.7866 in) 19.92 mm (0.784 in) 20.063 - 20 083 mm (0.7898 - 0.7906 in) 20.20 mm (0 795 in) 10.000 - 10.015 mm (0.3937 - 0.3943 in) 10.1 mm (0.40 in) 9.978 - 9.987 mm (0 3928 - 0.3931 in) 9.17 mm (0.361 in) 27.437 Intake Service limit OD limit Valves, valve springs and cylinder head Valve system OD: Intake Service limit Exhaust Service limit Valve guide ID - intake and exhaust Service limit 5.450 - 5.465 mm (0.2146 - 0.2152 mm (0.2134 in) 5.430 - 5.445 mm (0.21 38 - 0.21 44 5.40 mm (0.2125 in) 5.485 mm (0.21 56 - 0.21 59 5 475 5.50 mm (0.217 in) 1 9 22 Air-cooled twin cylinder sohc four-stroke 53 53 1 21 Engine Stroke 1 15 16 17 20 Crankshaft - inspection Initial start-up after major repair Recommended break-in procedure Specifications Type Bore 13 in) 5 42 in) in) 39 Chapter 2 Engine and transmission Valve stem to guide clearance; mm 0 010 - 0.035 0.08 (0.003 Intake mm Service limit 0.030 - 0.055 mm (0.001 2 - 0.0022 0.10 mm (0.004 in) 1-1 - 15 mm (0 04 - 0.06 in) Exhaust Service limit Valve seat width Service limit Valve spring free length: 1 Inner Service limit Outer Service limit Valve clearances - intake and exhaust Cylinder head maximum warpage across gasket face ' .8 mm (0.07 Cylinder bore ID - standard size bore Service limit Maximum taper Maximum ovality Maximum warpage across gasket face .1 53 000 53.1 0.05 0.05 0.05 - mm mm mm mm 53.010 (2.09 Piston pin bore ID Service limit (0.002 (0.002 (0.002 OD Service limit Piston pin to bore clearance Service limit Piston ring to groove clearance; mm +0.25 mm + 0.75 mm 1 5.002 5.05 1 mm (2.085 - 2.086 in) in), in), 008 mm +0.50 +1.00 mm mm 0.01 5 - 0.040 Second 0.01 5 - 0.045 0.1 mm mm mm (0.004 mm (0.004 mm in) (0.0006 - 0.001 8 in) in) (0.006 - 0.01 4 0.15 - 0.35 Crankshaft and connecting rods Connecting rod small end ID Service limit Big end bearing side clearance Service limit Big end bearing radial clearance Service limit Crankshaft runout - service limit Starter drive Driven sprocket boss inside diameter Service limit Driven sprocket boss outside diameter Service limit 0 1 mm in) mm mm (0 004 Plain plate warpage Service limit Primary drive type Primary reduction ratio in) in) 1 5 01 6 - 1 5.034 mm (0.591 2 - 0.591 9 in) 15.08 mm (0.594 in) 0.10 - 0.40 mm (0.004 - 0 016 in) 0.6 mm (0.024 in) 0.004 - 0 012 mm (0.00016 - 0.0005 in) 0.05 mm (0.002 in) 0.1 mm (0.004 in) 22.010 - 22 022 mm (0 8666 - 0.8670 22.08 mm (0.869 in) 36.975 - 37 000 mm (1.4557 - 1.4567 36.90 mm (1 .453 in) Clutch and primary drive Clutch type Clutch spring free length Service limit Friction plate thickness Service limit in) (0.0006 - 0.001 6 0.5 (0.02 in) 0.2 - 0.9 (0.008 - 0.036 in) Not applicable 0.01 - 0.04 (0 0004 - 0.0016 Piston to cylinder clearance Service limit in) in) Service limit mm 0196 (0.0393 (0.5906 - 0.5908 in) Top and second rail (0 1 4.994 - 1 14.98 mm (0.590 in) 0.002 - 0 014 mm (0.0001 - 0.0006 0.07 mm (0.003 in) 0.1 Service limit in) (0.593 in) 5.000 mm (0.5903 - 0 5906 Service limit Oil ring side in) in) 0098 Top Service limit Piston ring end gap - installed; 086 - 2.087 in) (0.0295 (0 5 (2 in) mm 52.97 - 52 99 52.9 (2 08 1 mm in) Pistons Piston OD - standard size bore Service limit Piston oversizes in) mm (1.18 in) mm (1 4 in) mm (1 50 in) mm (1 .46 in) mm (0.002 in) mm (0.004 in) 29.9 29.0 38.2 37.0 0.05 0.1 in) in) Cylinder bores Piston pin (0.0004 - 0.0014 in) Wet, multiplate 37 8 mm (1 49 in) 36.0 mm (1 .42 in) 2.8 - 2.9 mm (0.1 1 0 - 0.1 1 4 2,6 (0.10 in) 0-0.10 mm (0 - 0 004 in) 0.2 (0.008 in) Gear 3.631:1 (69/191) mm mm in) in) in) in), in) Chapter 2 Engine and transmission 40 Transmission Gear 1 ^fs'?"^ ratios: 0Qy1A-1 St t '7~J / A 'iT \ /'30/1QT\ 2nd 1 '^TJ•^ 3rd 4th 1 QOO'I ^0Q/01T\ Top 0.913:1 (21/231) Chain and sprockets 1.083:1 (26/24T) Final drive type 2.357:1 (14/331) Selector forks: Fork thickness Service limit Bore ID Service limit Selector fork shaft OD Service limit Gear pinion dimensions; Mainshaft 5th gear, countershaft 1st gear and countershaft 4th gear ID Service limit Countershaft 1st gear bush ID Service limit Countershaft 1st gear bush OD Service limit Gearshaft dimensions: Mainshaft, at 5th gear and clutch outer journals Service limit Countershaft at 1st gear journal Service limit Countershaft, at 4th gear journal Service limit Oil pump Inner rotor tip to outer rotor tip Service limit Outer rotor to body clearance Service limit Rotor end clearance Service limit 4.93 - 5.00 mm (0.1 94 - 0.1 97 in) 4.80 mm (0.189 in) 12.000 - 12.018 (0.4724 - 0.4731 12.05 (0.474 in) 1 1 .97Q - 1 1 .994 mm (0.471 5 - 0.4722 1 1 .93 (0.470 in) mm mm mm 20.020 - 20.041 mm (0.7881 - 0.7890 20.08 mm (0.791 in) 16.516 - 16.534 mm (0.6502 - 0.6510 16.58 mm (0.653 in) 19.979 - 20.000 mm (0.7866 - 0,7874 19.93 mm (0.785 in) 19.959 - 19.980 19.91 mm (0.784 16.466 - 16.484 16.41 mm (0 646 19.959 - 19.980 19.91 mm (0.784 mm in) in) in) in) in) (0.7857 - 0.7866 in) (0.6483 - 0.6490 in) (0.7857 - 0.7866 in) in) mm in) mm in) 0.15 mm (0.006 in) 0.20 mm (0.008 in) 0.15 - 0 18 mm (0.006 - 0.007 in) 0.25 mm (0.010 in) 0.01 - 0.07 mm (0,0004 - 0.0028 in) 0.12 mm (0.005 in) Torque specifications Component Engine mounting bolts: Front - 1 0 mm Rear - 1 0 mm Hanger plate - 8 Drive sprocket bolt mm Footpeg mounting bolt Exhaust pipe joint nut Muffler mounting nut Muffler joint bolt Cylinder head bolt Cylinder head/camshaft holder nut Cam sprocket bolt Cylinder head cover bolt Clutch hub nut Primary/oil pump drive gear nut Selector drum stopper plate bolt Gearshift pedal bolt m-kg Ft-lb 5.5-7.0 40 - 51 58 - 72 8.0 - 10.0 2.4 - 3.0 1.0-1.4 17-22 7-10 - 3.5 - 4.0 25 - 29 5-8 0.7 - 1.1 13 - 18 1.8 - 2.5 - 2.5 1.7 - 2.3 17-22 7-10 15-18 12-17 0.8 - 1.2 5.0 - 5 6 4.8 - 6.0 36 - 40 35 - 43 2.4-3.0 1.0-1.4 2.1 6-9 7-10 1.0-1.4 5-8 0.7 - 1.1 5.5 - 6.5 1.20.8 40-47 Bolts 2.0 - 2.5 Nut 1.0-1.4 14-18 7-10 Rotor bolt Starter clutch screws 6 Crankshaft center bearing plate: Oil feed plate * 1 Apply screws 9* 6-9- 0 8 - 1.2- a locking agent General information The conventional twm-cylinder, air-cooled overhead cam engine is simple by current standards, and is relatively easy to work on at home. The light aluminum alloy cylinder head carries just two valves per cylinder, and these are operated by rockers from the central camshaft. The cam is driven by a free play is controlled by an automatic tensioner assembly Hy-Vo type chain from the crankshaft. Chain The crankshaft assembly is supported between the vertically-split crankcase halves. The crankshaft is carried on large journal ball bearings. In addition, there is a center bearing assembly housed in a holder which attaches to the inside of the left crankcase half. At the right end of the crankshaft, power is transmitted through Chapter 2 Engine and transmission A second gear on the crankshaft engine oil pump. From the clutch, power is fed to the five-speed constant mesh transmission, and then by chain and gear's to the wet multlplate clutch. drives the sprockets to the rear wheel. Note that the construction of the engine/transmission unit makes most routine repair and overhaul operations quite simple, and few and it is always easier to work on the engine when it is positioned on a bench of convenient working height. 2 The following items cannot be repaired or removed unless the engine unit is removed from the frame: Crankshaft assembly and connecting rods Main bearings and transmission bearings Transmission shafts and gears needed Where non-standard tools be mentioned in the appropriate Section. Most assemblies inside the unit can be overhauled at home, the major exception being the crankshaft assembly and the center main bearing, which require specialist attention. specialised tools or procedures are are required, this will Major engine repair 2 Gear selector drum and forks Cylinder head, cylinder and pistons Cam chain and tensioner - general notes 4 1 The decision to perform a major engine overhaul is governed by a number of factors. If there has been an obviously serious failure, possibly resulting the need for a in internal full overhaul parts breaking or the engine seizing, then will be clear. In other circumstances the nature of the fault or faults will have to be considered and a decision as to whether a full overhaul is required, or if repairing a single item or assembly As will suffice. judge the general condition of the motorcycle. If has been well maintained, then the fault may be confined to an isolated failure; if it has been neglected or abused, other areas may require attention in addition to the immediate problem. Mileage covered is another factor to be considered, but is less significant than the past history of the machine. Exhaust smoke and excessive oil consumption are indicative of 3 wear or damage to the cylinder bores, piston rings, valves and valve guides. This can be checked further by performing a compression test as described in Chapter 1. A badly worn bore or rings is often characterised by a harsh metallic rattle from the cylinder area. Cam or rocker wear may be evident in the form of a rattle from the cylinder 2 a starting point, it head area 4 Obvious knocking or rumbling from the crankcase points to a fault in either the big end or main bearings, and this will necessitate a crankshaft overhaul. Although overhauling of the crankshaft should be left to an authorized dealer service department, it is still worth doing the preliminary dismantling work at home to save a significant part of the repair Rough bill. economy and generally do not always mean that ^n overhaul is needed. Sometimes a full tune up will restore the engine to normal, but if this fails to solve the problem, general wear is indicated and an overhaul 5 running, loss of power, poor fuel noisy running be necessary. full overhaul means dismantling the complete engine/transmission assembly so that the internal parts can be checked and restored to the specifications of a new engine The work is not especially difficult, but It is time consuming Read through the procedures carefully to familiarize yourself with the requirements of each operation. Where possible, order new parts, such as a full gasket and seal set, m advance. Remember that parts found to be worn as the engine is stripped down and inspected will have to be ordered, and time must be allowed for will 6 A this. ^^^---.^ Most overhaul operations can be undertaken using normal fiand tools, although some specialist equipment may be needed when 7 measuring wear. Even if facilities are limited, the unit can be dismantled and the various components and assemblies taken to a dealer service department or a motorcycle repair shop for measurement. This is also a good place to seek advice concerning reconditioning or renewal. Labor costs are a substantial part of any repair bill, but by carrying out the dismantling and assembly work yourself you can reduce the cost significantly. 3 41 Repair operations requiring engine removal Certain assemblies and components require the removal of the 1 engine unit from the frame so that the crankcase can be separated for access. In addition, the cylinder head, cylinder and pistons cannot be removed with the engine in the frame because there is insufficient clearance. The items requiring engine removal are summarized below, but It may be worth removing the unit if a number of other items require attention The removal procedure is not difficult or time-consuming. Engine - removal and installation Note: Engine removal and installation should be done with the aid of an assistant to avoid possible damage or personal injury The engine can be handled comfortably by two people The dry weight of the engine is 86 lb (39 kg) Before starting work, clean the engine and the surrounding frame area with a degreaser or by steam cleaning or pressure washing Take care to avoid ignition and electrical components when using a steam cleaner or pressure washer Use a stand or strong wooden blocks to support the motorcycle upright. Use ropes or webbing straps lashed to the frame tubes to secure the machine and check that it is supported safety in this position Check that you have adequate working space on both sides of the machine Remove the passenger seat mounting bolts, disengage the front of 1 the seat and remove it. Remove the rider s seat in the same way. 2 Remove the single mounting bolt at the rear of the fuel tank, and the boK on each side of the steering head. Check that the petcock is set to the 'Off position and disconnect the fuel line at the tank end. On California models, lift the tank and disconnect the tank breather line. Remove the single bolt which retains the right side cover. Hinge 3 down the cover and the battery holder. Disconnect the battery negative (-) lead, one side. 4 Place then the positive ( -i- ) lead. a drain tray of at least 2 crankcase. Remove Remove US qt (2 the battery and place liter) it to capacity below the the crankcase dram plug and leave the oil to drain. While the oil is draining, slacken the exhaust pipe clamps below the engine and remove the exhaust pipe joint nuts at the exhaust ports. Remove the muffler mounting nuts. Separate and remove the two halves of the exhaust system. 6 Release the gearshift pedal linkage from the shaft end by removing the pinch bolt. Pull the linkage off the shaft and then refit the bolt to 5 prevent its loss 7 Remove the rear section of the left side cover (sprocket cover). Trace back the alternator and ignition pickup wiring, releasing the wiring clips and separating the wiring connectors. 8 Apply the rear brake to prevent rotation and remove the final drive sprocket bolts. Pull the sprocket off the end of the transmission countershaft and disengage it from the drive chain. The chain can be left to hang against the frame tube. If it proves difficult to remove the sprocket, slacken the rear axle nut and the chain adjusters to allow the wheel to move forward, giving more chain free play. 9 Disconnect the starter motor cable from its terminal on the top of the motor Route the cable clear of the engine. 10 Disconnect the crankcase breather hose at the crankcase end. The clip securing the hose can be slid along after the ends have been squeezed together with pliers. The hose can then be pulled off its stub. 1 1 Slacken the clamp which secures the carburetor to the intake adaptor. The carburetor can be left attached to the air cleaner during engine removal if desired, or the throttle and choke cables detached and the instrument removed. The latter option is recommended because it provides more working space. Use a piece of wood to wedge the rear brake pedal down and clear 1 2 of the right footrest assembly. Alternatively, release the brake operating rod so that the pedal can drop clear. Remove the right footrest and its bracket as an assembly. "/Mii 13 Slacken the clutch cable adjusters, then detach the clutch caf»e,.ax >. Its lower end 14 Disconnect the spark plug caps and leads. It is helpful, but not essential, to remove the electrical plate which carries the ignition coils and wiring harness connectors just above the cylinder head cover. Tie the assembly to the frame, clear of the engine. To avoid accidental Chapter 2 Engine and transmission 42 damage, displace and remove the CDI unit from its rubber holder to the rear of the electrical plate. progresses. 5 Slacken the five engine mounting nuts and bolts, and also the three which secure the front mounting plate and engine hanger plates to the frame. Note the direction of fitting of the bolts. Displace and remove the bolts and plates, reassembling them to keep the bolts in the correct position while stored. 1 6 To allow the bolts to be displaced, use a length of timber to gently lever the engine upwards. This will take the weight of the engine and allow the bolts to be removed easily. Allow the engine to sit in the frame cradle, having wrapped some rag around the frame tubes to protect the paint finish. Check that 1 7 The engine is now ready to be removed from the frame the working area to the right of the machine is clear, then with the help of an assistant, lift the unit and slide it out to the right. Place the engine on the workbench to await further attention. 18 The engine is installed by reversing the removal sequence Note that the mounting bolts are inserted from the right side. Fit all the bolts loosely, then tighten them to the specified torque. 1 bolts 4 1 cables, wires and hoses as reassembly none will be trapped by steering movement or by the seaf-or fuel tank. Check that all electrical connections are secure. Before installing the fuel tank and seat, refit the battery and 19 Check the routing Lug on seat nose (arrowed) hooks under bracket on frame. Make of all sure that check that the electrical system functions normally 20 Refit the exhaust system, using new sealing rings at the exhaust ports. Fit the system loosely, then torque down from the front. 21 Install the seats and the fuel tank On California models do not forget to connect the tank breather line On all models, connect the fuel line and check for leaks 22 Check that the crankcase dram plug is fitted and tightened to the specified torque Replenish the crankcase with the recommended If the quantity of SAE 10W/40 type SE or SF motor oil (see Chapter 1 engine has been overhauled, a slightly greater amount of oil will be required. Check the oil level after the engine has been run for a few minutes. Refer to the end of this Chapter for information on the initial start-up after major engine work and on the recommended break-in ) procedure. 4 2a Rear of tank is secured by single rubber-bushed bolt Bolts retain rear of each seat 4.2b Front of tank steering head is held by dome-headed bolt on each side of the 4.3a Right side cover is secured by a single bolt 4.3c 4.5 Exhaust pipe retainer is secured by two 4.7b The sprocket and drive chain can domed now be ... then disconnect the battery leads nuts slid off the shaft 4 9 Release the starter motor cable from the motor terminal (arrowed) carburetor body 4 12 Wedge down or remove brake pedal, then remove footpeg assembly 4 13 Release adjuster and free the clutch cable from operating arm 4 14 Release the two bolts (arrowed) to free the electrical panel 4 11c Unscrew the choke plunger and pull assembly out of right side 4 18a Check and clean front engine nnount assembly before installing 4.1 4.18b Front engine mount is fitted as shown it Be Assemble engine hanger plate in position shown 4.19a Check that drain and breather hoses are routed through guide on underside of crankcase Chapter 2 Engine and transmission 46 4 19b Fit wiring and grommet through slot in crankcase 4.19c 5 Install A the drive chain and sprocket, then general outer cover is to keep all mated parts and also the valves and springs must during disassembly rule together. Items like the pistons, be installed refit in their original positions. This means marking parts as they and a permanent type felt marker being useful here Small parts are best k^ept in marked containers and stored well away from the work area to avoid disturbance. Any shims, spacers or washers should be placed on the end of the shaft from which they were removed. 6 When carrying out work with the engine in the frame, remove the fuel tank as described earlier in this Chapter to improve access. During a full overhaul, the disassembly operation should be carried out in the are removed, a small container filled with solvent for degreasing, following sequence, referring to the appropriate Sections for details: 4.20 Use M 5 new sealing rings in the exhaust ports the cylinder head cover and camshaft the cylinder head^''^9t^\ the cylinder the AC and pistons^ generator the starter drive and motor the clutch and primary gears the oil pump the external selector components Separate the crankcase halves Remove the transmission shafts, shift drum and forks Remove the crankshaft assembly Remove the crankcase bearings and fittings Engine disassembly and reassembly - general note Before disassembly commences, carefully clean off any residual dirt 1 with degreaser and rinse with water. A clean engine will make the job easier and prevent the possibility of dirt entering the engine internals. 2 In addition to the hand tools and equipment required for each operation, you will need a torque wrench, oil line brushes for internal cleaning and a valve spring compressor. If available, a motorcycle piston ring removaf and installation tool will make this operation much easier, but it is possible to do the job without one. 3 You will also need some engine oil (SAE 10W/40 type SE or SF), some molybdenum disulfide grease, and some thread locking compound (Loctite or similar). Other specific expendable items will be mentioned in the text, where they are required. 4 If the engine is on the workbench it is advisable to construct a stand which will support the engine in a number of different positions. A simple engine stand can be constructed from short lengths of 2 x 4 in lumber, in the form of a shallow box with no base. A simpler method is to collect a selection of wood blocks so that the engine can be propped in Remove Remove Remove Remove Remove Remove Remove Remove the required position. 6 Camshaft and rockers - removal, inspection and installation Removal 1 If the frame, pull off the spark plug caps and loosen the two cylinder head cover bolts and lift off the cover is stuck, tap around the gasket faces with a the engine the spark plugs. is in Remove the cover If soft-faced hammer, or use a conventional hammer and a hardwood block. 2 Slacken the cylinder head holding bolts and nuts in the reverse order of the sequence shown in the accompanying line drawing. The bolts and nuts should be slackened m several stages to avoid warping the cylinder head. Remove the nuts which secure the camshaft holders, then lift away 3 the holders. Remove the locating doWels and place them with the holders for safekeeping. Prepare marked boxes to hold each cam holder and rocker parts: the rockers must not be interchanged bolt into the 4 Working on one camshaft holder at a time, fit a 5 end of each rocker shaft and use this to pull the shaft out Place the mm Chapter 2 Engine and transmission Use locking agent on the bolt threads, and tighten to the prescribed torque setting. 21 Turn the crankshaft counterclockwise until the remaining bolt can be installed and tightened to the recommended torque setting. Turn the crankshaft counterclockwise until the T' mark is in alignment, and rocker and spring together in a marked box. Repeat this procedure on the rehnaining rockers, keeping them separate. Remove the spark plugs, then plug the holes with rag to prevent 5 dirt falling into the cylinders. Remove the large inspection cap in the center of thtf left crankcase side cover (AC generator cover). Pass a socket through the inspection hole and turn the crankshaft counterclockwise until one of the cam sprocket bolts is accessible. Pack some clean rag around the cam chain tunnel area to pi^vent either of the bolts falling into the engine if inadvertently dropped^ Remove the bolt, then continue turning the crankshaft counterclock-wise and shaft, remove the second bolt. The cam chain tensioner should 6 -This requires a riv^t to 7 2 mm now be released and 'locked pin for locking purposes - we found a small fitted. check that the cam sprocket marks If upwards, at the remove the sprocket parallel to the cylinder head face. and reposition the chain on the lie bolts the marks align correctly. the valve adjusters, and fit the dowels into their holes in the cylinder head. Install the camshaft holders with the 'F' mark towards the front of the engine. Fit the cylinder head bolts, nuts and until 22 Loosen fully washers. Tighten off, in several stages to prevent sequence same time pressing the lower assume its normal position automatically. 23 Prime the camshaft lubrication system by pouring oil into the pockets around each camshaft lobe until it is partially submerged. If the cylinder head cover seal is damaged or broken, fit a new one. Offer up the cover, then fit and torque tighten the holding bolts. 24 Complete reassembly by reversing the removal sequence. Start the engine, and allow it to run while checking for leaks. Stop the engine and allow it to stand for some time. Check the engine oil level and top up as required tensioner will wedge down. When the small hole in the upper wedge aligns with the tensioner bracket, slip the pin into place to lock it, 8 Slide the camshaft sprocket to the left until it comes off the shoulder .Disengage the sprocket from the cam chain. Pull the camshaft ouT^^rom the right side and remove the sprocket. Place a piece of wire througtKthe chain loop to stop it dropping down into the crankcase. Inspection 9 Clean all parts carefully with solvent and dry them. Again, make sure that the various parts are kept separate in their marked containers. 10 Examine the camshaft lobes for wear, scoring or discoloration. If worn damaged, the camshaft must be renewed. Check also the pad at the end of each rocker which runs on the camshaft lobe. If the cam lobes are scored or badly worn it is likely that similar damage will have been sustained by the rockers If so, the rockers must also be significantly or ' renewed. 1 1 Check the height of each camshaft lobe and compare the readings with those given in the Specifications. If below the service limit, renew the camshaft. This measurement is made using a micrometer; if you do not possess this equipment, have the measurement made by a dealer service department. 12 Inspect the bearing surfaces at each end of the camshaft, and also the inner surface of the camshaft bushes Note that the left bush is retained by a circlip and spacer. If damage is found, renew the camshaft and bushes. 13 Measure the camshaft bush inside diameter (ID) and the camshaft journal outside diameter (OD) using the appropriate micrometer, or have this work carried out by a dealer service department. If either part is outside the service limit, it is in need of renewal. 14 Support the camshaft between V-blocks and set up a dial gauge so that the probe rests on the sprocket shoulder. Turn the camshaft and check the amount of runout indicated. If this is outside the service ' limit, renew the camshaft. 15 Check the rocker inside diameter and rocker shafts for wear or damage. Check that the oil holes in the rockers are clean. Measurei'the>. rocker bores and shafts and compare wttfi the specifications. ^enew i the rockers and/or shafts if worn or damaged. i . Installatian 16 Check that all parts are clean. Assemble the rocker arms, springs and shafts, noting the following points. Lubricate the shafts with engine oil before installing them Make sure that the threaded end of each shaft faces outwards. 17 Fit the bushes, after lubricating them with engine oil, on the ends of the camshaft. Fit the spacer to the left end of the camshaft, engaging its tab in the slot provided. Fit the circlip to retain the spacer and bush. 18 Pass the camshaft from the right side through the cam chain loop, noting that the shoulder for the sprocket must face the left side. Place the sprocket over the cam as it is positioned in the cylinder head. The timing marks on the sprocket should face the left side. Align the knock pins In the cam bushes with their slots in the cylinder head. 19 Remove the timing inspection plug from the left side cover Turn the crankshaft counterclockwise until the T' mark coincides with the index mark at the top of the inspection hole. 20 Fit the cam sprocket into the chain loop so that the timing marks align with the cylinder head surface (photo). Position the sprocket over the cam shoulder, then turn the cam until one of the bolts can be warpage following the shown in the accompanying illustration. Tighten all fasteners to the recommended torque. Check and adjust the valve clearances (refer to Chapter 1 ). Remove the tensioner locking pin; the pop be ideal (photo). it not, sprocket M the top of the tensioner are two wedges. Grasp the upper wedge with pliers and pull 47 6 6 Lock cam chain tensioner with a 2 mm pin 6.19 Align the T' mark with the index line at top of inspection hole 6.20a Lines on sprocket face should be parallel with gasket surface 6 23 Install cylinder head cover, using new gasket if needed 1 50 .OS.' Fig. 2.1 2 Camshaft Bushing 2 3 4 Knock pin Washer 5 6 Circlip 7 Left side 7 off 2 off 8 9 Front dowel pin Rear dowel pin Right side camshaft holder 10 Nut - 8 off 1 camshaft holder Camshaft and valves (Sec 6 and Washer - 8 off 12 Rocker arm - 2 off : <• 13 14 15 16 8) Spring - 2 off Rocker shaft - 2 off Locknut - 2 off Adjuster screw - 2 off 1 7 Keepers - 4 off 18 Retainer - 2 off 19 Inner valve spring - 2 off 2 off valve spring 21 Seal -2 off 22 Spring seat - 2 off 23 Exhaust valve 20 Outer 24 Intake - valve Chapter 2 Engine and transmission Fig. 2.3 51 Cylinder head nut tightening sequence (Sec 6) Reverse the sequence when slackening Fig. 2.2 Cam chain tensioner locking method (Sec 6) Inspection 7 Cyhnder head - removal, inspection and installation I Carefully remove all traces of the old cylinder head gasket from the and cylinder gasket faces. Use pieces of rag to prevent cylinder head debris falling into the cylinders. Removal the engine from the frame (Section 4) Remove the cylinder head cover, camshaft holders and camshaft (Section 6) 1 Remove 2 Remove the intake adaptor from the rear of the cylinder head (four nuts). 3 Remove the cam chain tensioner upper bolt and slacken, but do not remove, the tensioner lower bolt. 4 Remove the three remaining bolts which secure the cylinder head. Note that the single front bolt screws into a captive nut held in the cylinder casting. This nut may drop free when the bolt is removed retrieve it and screw it onto the bolt for safekeeping. 5 The cylinder head can now be lifted off the cylinder block. It may be found that the gasket tends to stick it firmly to the top of the cylinder block. If this occurs, try using engine compression to break the seal, on no account attempt to lever the joint apart. Refit and tighten the spark plugs. Lift the cam chain loop and pass a bar through it. If this is kept taut during this operation it will stop the chain bunching around the crankshaft sprocket and jamming it. 6 Using a socket on the AC generator nut, turn the crank to apply compression pressure on the underside of the head. With luck, this will force the head away from the cylinder. 7.2 Intake adaptor is retained by tour studs and nuts Remove the accumulated carbon from the combustion chambers 8 using a brass scraper to avoid scoring the soft aluminum alloy. Wash all traces of debris off the cylinder head with solvent and dry it, If the cylinder head gasket has blown, check the cylinder head 9 gasket face carefully for erosion near the break in the gasket. Check the head surface for warpage by placing it on a flat surface (a sheet of glass will suffice) and checking for clearance with feeler gauges. If the head IS damaged or warped beyond the service limit, it must be skimmed flat in an engineering shop, or renewed. Installation 10 Check that the gasket faces are clean, and fit a new cylinder head gasket onto the cylinder gasket face. Fit the dowel pins into their recesses m the top of the cylinder Fit new seals around both right outer studs and the left rear outer stud, II Fit the cylinder head, feeding the cam chain through the center tunnel. Fit the cam chain tensioner upper bolt and then tighten both tensioner bolts. Refit the intake adaptor, using new 0-rings if the old ones are flattened or broken 12 Install the camshaft, camshaft holders and cylinder head cover as described in Section 6. 7.5 Lih head clear of holding studs. Use wire to stop chain dropping into crankcase 52 Fig. 2.4 Cylinder head and block (Sec 7 and 9) Chapter 2 Engine and transmission 8 53 compound and repeat the process. 14 Periodically remove the valve and clean its contact face and that of the valve seat. Inspect both parts, checking that there is an unbroken matt gray line denoting the contact area. If this turns out to be deeply redistribute the Valves: disassembly, inspection and installation Before attempting an overhaul of the valves, note that a valve is essential. Without this tool it is not possible to remove and install the valves safely. If you do not have a suitable compressor, valve servicing is best left to a dealer service department. If a compressor is available, it is possible to disassemble the valves, 2 check them visually for wear or damage, check the valve seats and to reassemble them. To carry out a full dimensional check of the various parts specialist measuring and reconditioning equipment is essential. If a full valve job is needed this is best left to a dealer service department. Despite this limitation, a good proportion of the repair bill will have been saved by doing the preliminary work yourself. 1 spring compressor pitted or scored, do not continue the lapping operation further; either renew the valve or have the valve seat renewed and recut, then resume the lapping operation. 15 When the lapping operation is finished, carefully remove every compound from the cylinder head and valves. On no account allow any trace of the compound to remain or it will cause serious damage to the engine. trace of the abrasive Reassembly 16 Lubricate and install guides, pressing each new valve stem seals on each of the valve one down squarely and firmly over the end of cylinder head and carry out initial cleaning and inspection as described in Section 7. If the cylinder head is seriously damaged or cracked, the valve job need not progress further since a new or reconditioned head will be needed. 4 Before removing the valves, have ready marked boxes in which each valve, spring, keepers and retainers can be stored separately. Mark each box to identify the valve in question, eg 'left intake' and 'right exhaust'. Assemble the valve spring compressor making sure it is located Tighten the compressor until the retainer moves down enough to allow the keepers to be dislodged and removed. Do not over compress the valve springs. If the assembly seems stuck, tap the end of the compressor to free it rather than applying excessive pressure. 6 Use a magnet or pliers to remove the keepers. Do not use your fingers in case the compressor slips out of position. Remove the retainer and the valve springs. Displace and remove the valve. If it sticks in the guide, remove any carbon present around the head of the 5 securely. removed. 17 Lubricate the valve stems with molybdenum disulfide grease and install them in their respective guides. Fit the spring seats and springs with their tightly-wound coils facing the cylinder head. Refit the retainers, then assemble the compressor, tightening it just enough to allow the keepers to be fitted. A small dab of grease will hold the keepers in place on the valve stem while the compressor is removed. Carefully remove the compressor, then tap the end of each valve once or twice to make sure that the keepers are seated correctly. 18 The reassembly operation is concluded by refitting the cylinder head and camshaft, as described in Sections 6 and 7. Do not force the valve through the guide or the guide bore will be damaged. Place them in their marked box, then repeat the removal operation on the remaining valves. valve. Inspection Clean each part in solvent and dry it with lint-free rag. The valve 7 springs should be checked for length and renewed if they have compressed to or beyond the service limit. This is best done using a vernier caliper, but if care is taken an accurate rule will give a good indication of the free length of the springs. 8 or Inspect the valve for wear or damage. If the stem is scored or bent, the valve contact face is pitted, renew the valve concerned. Honda if recommend grooved or that the valve contact face pitted. A new valve is cannot be ground if worn, the only cure. Inspect each valve guide bore for damage or scoring. Check the fit each valve stem in its guide. To assess wear accurately, you will need to have the valve stem diameters and guide bore diameters measured at a dealer service department. Subtract the valve stem OD from the guide ID to obtain the stem-to-guide clearance. If this exceeds the service limit, the valve and/or the guide must be renewed. Renew the guide first, and if this does not bring the clearance within 9 of Compress valve springs removed 8.5 just enough to allow keepers to be renew the valve. 10 Valve guide renewal requires the use of a stepped driver and a reamer to finish the new guide to the correct size (5.47 mm). The guides must be removed and refitted after heating the cylinder head to 100°C (212°F) in an oven, taking appropriate precautions to avoid burns. The operation requires considerable expertise to perform, and it is quite easy to ruin the cylinder head if things go wrong. For this reason, it is advisable to have the work done professionally. limits, 1 1 If its guide. Note that the seals should not be re-used after they have been Disassembly Remove the 3 the valve seats are scored, burnt or pocketted, or if the valves and/or valve guides have been renewed, the valve seats must be recut to suit. This operation requires a set of valve seat cutters and experience in their use. Once again, entrust the work to an expert. 12 Before reassembly commences, the valves should be lapped to ensure a good seal between them and the valve seat. You will need some fine lapping compound and a hand lapping tool. These can be obtained from most auto parts stores. 13 Apply a small amount of the compound to the valve contact face, keeping it well away from the stem. Fit the valve into its guide, using a little oil on the valve stem as it is inserted Fit the lapping tool to the valve head (the valve head must be clean or the tool will not stick to it). Applying slight pressure on the valve, turn the tool back and forth between the palms of the hands. After a while you will notice that the grinding action of the compound cannot be felt. Lift the tool slightly to 8.6a Lift away the retainer, then the inner and outer valve springs Chapter 2 Engine and transmission 54 JBam 8.6b Displace and remove the valve 8.16 new Fit valve stem oil 8.7 seals to top of valve guides Check the 8.17 Fit free length of each valve spring valve springs with close-wound coils nearest to cylinder head 9 suit. Cylinder block - removal, inspection and installation Removal 1 Refer to tfie previous sections and remove the cylinder head cover, camshaft and cylinder head. 2 Remove the cylinder head gasket, then lift out the dowel pins and stud seals. 3 Lift out the tensioner guide blade. mounting bolt. 4 Tap around the base Remove the tensioner lower hammer to bores. off the gasket faces of the crankcase and the the cylinder in degreaser and dry it. Carefully clean cylinder. Wash Inspection 1 will for scoring or other damage. If found, this reboring to the next oversize and the fitting of new pistons to Examine the bore surface mean reboring is required, take the cylinder to a dealer service calculated. of the cylinder with a soft-faced loosen the joint. Lift the cylinder by an inch or so, then pack rag into the crankcase mouth to catch any debris which might otherwise drop into the crankcase. 5 The cylinder can now be lifted clear of the pistons. Take care to support the pistons as they emerge from the bottom of the cylinder 6 If department to have the work done. 8 If there are no obvious signs of damage, check the condition of the cylinder bores by measurement. This operation requires the use of an accurate bore micrometer. If you do not have access to this equipment, have the measurements taken by a dealer service department who will be able to advise on reconditioning the cylinder, and may be able to arrange any necessary work. If you take this course of action, take the pistons so that they can be measured and the piston to bore clearances 9 The bore measurements are taken at three points; near the top of the bore, at the center and near the base. At each point, measure along the piston pin axis, and at right angles to it. Compare the readings taken with the specifications. If the bore surface is excessively tapered department or motorcycle repair shop to be rebored and honed 10 If the cylinder bores prove to be within the specified limits and undamaged, honing the bore surfaces is all that is required. The honing operation is designed to lightly roughen the bore surface so that it will hold a certain amount of oil It is especially important if new piston rings are to be fitted. Without honing, the new rings will never bed m to the bore surface, and the top ring may be damaged if it hits against the inevitable wear ridge at the top of each bore. or out-of-round, take the cylinder to a dealer service Chapter 2 Engine and transmission 55 To perform the honing operation you will need the correct size of hone with fine stones, some light oil or honing oil and an electric drill motor. Hold the cylinder between soft jaws or wood blocks in a vise. Fit the hone into the drill motor. 2 Lubricate the cylinder thoroughly, compress the honing stones and slip the tool into the cylinder Turn on the drill and move the hone up and- down the bore at a rate which will produce a fine Crosshatch pattern on the cylinder wall with the honing marks intersecting at about 60°. Use plenty of oil, and remove no more metal than is 1 1 flexible 1 essential to cover the entire bore surface. 13 Periodically, stop the drill with the hone still in the bore, then withdraw the hone and check the bore surface Sometimes fhe honing operation will highlight the step near the top of the bore If this seems deeper than it first appeared, it may be necessary to have it removed with a de-ridging tool. Most repair shops can carry out this work for you, and will also hone the bores if you do not have the necessary equipment 14 After the honing operation, wash the cylinder thoroughly to remove all traces of the abrasive grit produced during the honing The cleaning operation should include the stud holes. After and drying the cylinder, apply a coating of light oil to prevent rusting of the machined surfaces. process. rinsing t Installation 15 Before commencing installation, be sure to check the pistons and piston rings as described in the following section 16 Make sOre that the gasket faces are clean and dry. Fit the dowel pins into their recesses in the crankcase Place a new cylinder base gasket over the studs, feeding the cam chain loop through it. 17 Position the ends of the piston rings at 120° intervals If using piston ring clamps, fit these over the rings, following the manufacturer's instructions If fitting the pistons into the cylinder bores by hand, it is preferable to have an assistant to control the cylinder while new 9.16a Fit a 9.16b Install 9.20a Do cylinder base gasket the rings are fed into the bores. 1 8 Attach a length of wire to the cam chain loop. Apply a coat of oil to the bore surfaces. Position the cylinder above the pistons and feed the cam chain through the center tunnel with the attached wire. 19 Lower the cylinder down over the studs, keeping the cam chain As the bottom of the cylinder bores near the tops of the pistons, carefully feed the rings into the tapered lead-in at the bottom of each one. Make sure that the rings enter fully and that no part remains outside the taper, then push the cylinder down slightly and repeat the operation on the remaining rings. 20 If using ring clamps, tap the barrel downwards until the rings have engaged in the bores, then remove the clamps Remove the rag from the crankcase mouths, then tap the cylinder down onto the base taut. gasket. Refer to the appropriate Sections, and install the cylinder head, camshaft and cylinder head cover. 9.19 Lower cylinder base of bores down over studs. Feed rings into lead-in at the dowel pins in crankcdse gasket face not omit dowel pins and seals on top surface of cylinder Chapter 2 Engine and transmission 56 face and position on the piston. Place the rings and the piston \ marked container before removing the rings from the other in a piston. Inspection 10 Carefully clean each piston to remove the carbon deposits on the crown and around the ring grooves. Remove heavy crown deposits by scraping, then use a hand-held wire brush to remove the remainder Do not use power tools or anything which might score the soft aluminum material. 11 The piston ring grooves can be cleaned out by careful scraping A piece of broken piston ring makes an ideal tool for this job (ask your shop if you do not have anything suitable). Be very careful removing any of the piston material at the sides of the grooves, local repair to avoid or nicking or scoring them. 12 Once the crown and ring grooves are clear of deposits, clean the iji solvent and dry it thoroughly. Check that any oilways are cleaned out. 13 Inspect the piston surface for scoring or scuffing damage. General wear or scuffing may be due to the high mileage covered by the engine, or on a newer engine, to dirty oil or infrequent oil changes, or to poor piston 9.20b Fit a new head Arrows indicate gasket and insert the dowels over the studs. seal positions 10 Pistons - removal, inspection and installation Removal 1 Refer to the previous sections and remove the cylinder head cover, camshaft, cylinder head and cylinder Make sure that the crankcase mouth is completely covered by rag to prevent a dropped circlip from falling into the crankcase. 2 Each piston is supported on a piston pin which passes through the piston bosses and the connecting rod small end eye. The pin is located in the piston by a circlip at each end of the piston bore. 3 Using pointed-nose pliers, grasp the circlip at the removal slot and remove it. Note that new circlips will be needed during installation. Check that the piston pin bore is clean, and remove any accumulated carbon so that the pin will come out easily. The pin can now be pushed out from the inside face of the piston. 4 The pin should normally come out easily, but if it proves to be tight, do not try to drive it out or the piston or connecting rod may be damaged. Instead, warm the piston by wrapping a rag soaked in nearly boiling water around it. Wear protective gloves when doing this and be careful to avoid scalding yourself The heat will cause the aluminum piston material to expand, allowing the pin to be removed easily. 5 In rare cases, more effort will be needed to remove the pin, for which a piston pin removal tool will be needed. These can be purchased from tool and auto parts stores, and should be used in conjunction with the manufacturer's instructions. Alternatively, use a length of threaded bar or studding to make up the simple drawbolt tool shown in the accompanying drawing. 6 As each piston is removed, mark it to denote the bore to which it belongs. This can be done by marking the inside of the piston skirt with a scriber or felt-marker. Note that if grevious inspection of the cylinder bores has indicated that a rebore is required, do not continue with piston inspection or ring removal. 7 .'The piston rings should be removed from the piston before inspection. Use a proprietary ring removal tool. These can be obtained "from a tool or auto part store, and should be used in conjunction with the manufacturer s instructions. 8 With experience, the rings can be slipped off the piston after gently spreading the ring ends with the thumbs. This technique is fine for the professional mechanic, who does the job often, but for home use, play safe and slip old feeler gauge strips between the ring and the piston at three or four equidistant points around the ring. This will spread the ring enough to allow it to be removed, but without the risk of breakage due to spreading the ring too far. 9 As each ring comes off the piston, note that the top ring should have a plain working face, and the 2nd ring a tapered one. In each case, the top face of the ring should carry a number or mark near one of the ring ends. If this is indistinct, mark each ring to denote its upper . , oil circulation due to a worn or damaged oil pump. If the latter is suspected, check the oil pump or the wear problem will soon reappear (Section 12). 14 Streaks of burnt oil deposits on the piston skirt can often indicate wear in the piston rings and/or cylinder bores. Serious damage, like a hole burnt through the piston crown or a deformed piston crown, are usually due to pre-ignition caused by carbon build-up, or to spark knock (detonation). 15 Check the entire piston surface for mechanical faults, such as cracking around the bottom of the skirt, at the piston pin bosses, and around the ring grooves Reject any piston damaged in this way or it may fail if re-used, resulting in extensive engine damage 1 6 Measure the piston diameter at a point 1 0 above the bottom of the piston skirt and at 90° to the piston pin bore. Check that this does not exceed the specified service limit, then use the diameter figure in conjunction with the cylinder bore diameter measurements (see Section 9) to calculate the piston-to-cylinder clearance. Provided that this is within the service limit figure, the piston can be re-used if it is serviceable in all other respects. 1 7 Use a bore micrometer to measure the piston pm bore (check both sides). Measure the piston pin, then compare both measurements with the specified service limits. Renew the piston pin or the piston assembly as required Measure the inside bore of the connecting rod small end. If this exceeds the service limit, the crankshaft must be removed for reconditioning or renewal. Note that if you do not have the necessary measuring equipment for the above checks, have the work done by a dealer service department or repair shop. 18 Check the piston-to-groove clearance (top and 2nd rings only) with feeler gauges. If the clearance exceeds the service limit, check again with new rings. If this fails to cure the excess gap, renew the mm piston. 19 To check ring wear, push each one into the make sure bottom of its cylinder square to the bore and about 10 mm from the bottom of the bore surface. Check the installed end gap of the ring using feeler gauges and compare with the bore, using the top of the piston to specified service it sits limit. checks on the rings do not apply to the oil ring people prefer to renew the rings as a precautionary measure each time the engine is overhauled. In view of the limited cost of the rings and the amount of work required to disassemble the engine should the rings fail later, this can be considered a wise move if finances permit. 20 Note that the expander. Many Installation new rings are to be fitted, check their end gaps as described unusual for these to be outside the specified range. In cases where the end gap is bigger than specified, this can be due to wear in a used bore, or poor machining tolerances if the cylinder has been rebored. On a used bore this is acceptable, unless of course the end gap exceeds the service limit, in which case a rebore will be needed, rather than new rings. 22 On a rebored cylinder, however, you may wish to check the finished bore size by accurate measurement and then discuss the situation with the engineering shop or dealer service department before proceeding further. The other possible cause of the problem is that the wrong rings have been supplied and that they are just too big 21 If above. It is Chapter 2 Engine and transmission or too small. Again, check 57 this with the supplier before progressing further. 23 Check that the piston is clean and lubricate the ring grooves with engine oil. Fit the rings in the reverse order of removal. Place the oil ring expander in its groove, making sure the ends butt together and do not overlap. Work the lower rail into place first, then the upper rail. Do this by hand, not with the ring removal/refitting tool, and check again that the ends of the expander do not overlap. 24 Fit the 2nd ring next, then the top ring, each with its marked face upwards. Check that the top (plain faced) and 2nd (tapered face^ rings are fitted to their correct grooves. Check that all rings rotate smoothly grooves, and position the ring ends at 1 20° intervals. In the case (3/4 - 1 V4 in) of the oil ring, the ends of its rails should be 20 - 30 in their mm apart. 25 Apply molybdenum disulfide grease to the connecting rod small Fit the pistons to the connecting rods with the IN' marking on the piston crowns facing the intake side, and retain them by sliding the piston pins into place. Fit new circlips to retain the piston pins. Never reuse old circlips or they may work loose in use and cause serious engine damage. Position the ends of the circlips opposite the removal ends. slots. 26 Continue installation by refitting the cylinder, cylinder head, camshaft and cylinder head cover as described in the previous 10.3a Pry out the sections. 10.3b Piston pin can now be displaced and removed 10.19 Using feeler gauges to measure ring end gaps circlip with pliers or a scriber 10.9 Note markings on upper surface of rings, near gap 10.25 Fit pistons with 'IN' marking on intake side Chapter 2 Engine and transmission 58 Piston pin removal drawbolt tool (Sec 10) Fig. 2.5 11 '4 Drawbolt 1 2 3 5 6 Piston pin Tube Washer Nut Rubber washer Fig. 2.6 Clutch - removal, inspection and installation Note: If primary drive gear removal is intended it is necessary to slacken the retaining nut before the clutch is removed This can be accomplished by utilising the tool described in the following section to lock the engine via the clutch Remo val This operation can be undertaken with the engine in or out of the If the engine is in the frame, the engine oil should be drained and the clutch cable disconnected, before proceeding further. 1 frame 2 Slacken and remove the right side cover screws. If they seem tight, use an impact driver to avoid damage to the screw heads. Sketch the outline of the cover on a piece of cardboard, and push each screw, complete with any retaining clip, through the card in the appropriate position. This will keep the screws safe and in the correct sequence. Lift away the right side cover, if necessary having tapped around 3 the gasket face with a soft-faced hammer to help break the seal. Use a rag to mop up any residual oil. the clutch release lever requires attention, free the cam on the inside of the cover by removing the retaining pin. The release lever and 4 If shaft can then be withdrawn. Unless obviously worn or broken, the need not be disturbed. Withdraw the lifter rod and lifter rod guide from the center release lever parts 5 lifter plate. Remove the clutch lifter plate bolts, slackening of the them in a diagonal sequence and in three or four stages. Lift away the lifter plate and bearing and the clutch springs. 6 The clutch center nut is retained by staking it to a slot in the shaft end. Before it can be removed, this staking must be released by drilling or grinding it away. Be careful not to damage the shaft threads during this operation 7 To release the clutch center nut, you will nee a clutch center holder and a special wrench, available from a dealer service department. We improvised these tools, using the home-made clutch holding tool shown in the accompanying drawing and photograph, and a fabricated Once away the 8 wrench made up from a length of steel tubing. the clutch center nut and washer have been removed, lift clutch center, judder seat, judder spring, friction and plain plates, pressure plate and splined washer. The clutch outer can now be the shaft, followed by the outer guide and thrust washer. Note may be impeded if the oil pump and primary gear teeth do not coincide. If this happens, turn the assembly until the outer can be slid off. Reassemble the clutch parts to keep them slid off that removal of the clutch outer together and in the correct sequence. of removing piston rings (Sec 10) corresponding outside diameter of the c),uter guide. If worn beyond the specified limit renew the part(s) concerned. 11 Check the gear teeth around the clutch outer. If these are worn, chipped or broken, renew the clutch outer and the primary drive gear as a pair. Measure the If compressed to the renew the springs as a set. 13 Check the clutch plain and friction plates for signs of damage. 1 4 Check the plain (metal) plates for warpage by placing each one flat on a surface plate and measuring any gap with feeler gauges. Renew any plate which exceeds the service limit. _ 15 Measure the thickness of the lining material on each friction plate. If any are worn down to the service limit, renew the plates as a set. 16 Check the condition of the clutch lifter bearing by turning it. If it feels loose or gritty when turned, or if it seems unusually stiff, it should be renewed. Warm the lifter plate in near boiling water to expand the 1 2 free length of the clutch Springs. service limit or beyond, precautions to avoid burns. Support the plate on wood drift. Fit the new bearing by reversing the procedure, making sure that it enters the plate square to the bore, and it seats fully. Drive it in using a socket against the outer race only. alloy, taking blocks, then drive the bearing out using a socket as a Installation 17 Lubricate the thrust washer and outer guide with engine oil and place them over the shaft end. Install the clutch outer, making sure that the gear teeth engage with 1 8 those of the primary gear. Fit the splined washer with its sharp edge towards the clutch outer 19 Fit the flat judder spring seat onto the clutch center, then fit the conical judder spring. Assemble the clutch plates on the clutch center, starting with a plain (metal) plate and fitting thepi alternately. Finish off with a friction plate. Note thai if new plates are being fitted, soak ., them in engine oil for a while before fitting. , 20 the pressure plate to the inner face of the clutch center,''fhen^ arrange the tangs of the friction plates so that they align 21 Install the center assembly in the clutch outer. Fit the lock washer With the face marked OUTSIDE' visible. Fit a new clutch center nut, hold the clutch center with the tool used during removal, and tighten Fit the nut down to the specified torque figure. Stake the collar section of the nut into the shaft groove using a punch and a hammer. 22 Fit the clutch springs, then install the four bolts by hand only. Continue tightening in stages in a diagonal sequence until each bolt stops. 23 Fit lifter the headed lifter guide into the center of the bearing, then fit the rod. the dowel pins into the gasket face, if these were removed. new cover gasket in position. If disassembled, refit the lifter lever components in the clutch cover using a new retaining pin and 0-ring. Offer up the cover, then fit and tighten the retaining screws. Reconnect the clutch cable, then adjust the clutch free play (Chapter 24 Inspection 9 Check the Method Fit Place a caused by the corrected by deeply indented or slots in the clutch outer for indentations action of the clutch plate tangs. Light damage can be carefully filing the sides of the slots smooth. If cracked, renew the outer. 10 Measure the inside diameter of the clutch outer boss and the 1) Replenish the engine oil and test run the engine. Check that the clutch operates smoothly and that there are no oil leaks. 11.4 Clutch release arm cam is retained by a pin (arrowed) 4 11.15 Measure the friction plate 11.17b Lubricate and install thicknesses the clutch outer guide 1 1 1 1 1 7a 1 8a Install Install the thrust washer over shaft end the clutch outer 1 1 .1 8b Fit the splined washer over shaft splines 1 1 .1 1 1 .1 1 1 1 9d Finish with a friction plate 9a Place the judder spring seat onto clutch center 9c Assemble the plain and 11.21a Fit friction plates alternately the pressure plate, align tangs and install assembly b Tighten down the clutch center nut, then stake shaft groove to lock it 1 1 .21 11.22b Install the lifter plate over springs it into the 1 1 1 1 22a Place the clutch springs over the posts 22c Tighten bolts in a criss-cross pattern in small steps Fig. 2.7 7 2 3 4 5 6 Clutch (Sec 11) L/fter lever 0-ring Return spring Lifter cam Pin Lifter rod 7 Headed 8 9 bearing Bolt - 4 off 10 Lifter plate lifter rod Lifter Spring - 4 off 12 Clutch center 13 Spring seat 14 Judder spring 15 Splined thrust washer 16 Friction plate - 6 off 1 7 Plain plate - 6 off 18 Pressure plate 19 Clutch outer 20 Outer guide 1 1 1 1 .24 Install the cover using a new gasket. Do not omit dowel pins 21 Thrust washer Chapter 2 Engine and transmission — 63 Clutch center To remove the primary gear retaining nut it is necessary to devise a method of preventing the crankshaft from turning. The official method uses a gear holder to lock the primary gear and clutch outer gear together. The tool consists of a piece of metal shaped like a sector of a gear. Its teeth are engaged in those of the gears to be locked. This tool 4 Judder spring - Fig. 2.9 Spring seat Clutch judder spring and seat fitting details (Sec 11) 12 Oil pump, primary drive gear and removal, inspection and installation oil pump drive gear - Removal 1 in The items covered the frame or on the in this section can be workbench worked on with the engine engine oil and is available from an authorized dealer service department. In the absence of the correct tool, you could make up a suitable 5 device in the workshop from scrap materials. If you take this approach, make sure that that tool fits correctly and does not place undue loadings on the gear teeth. 6 Another method can be applied if the cylinder head, cylinder and pistons have been removed. Place small wood blocks across the crankcase mouth on each side of one of the connecting rods. Pass a smooth round steel bar through the connecting rod small end eye, resting its ends on the wood block. Turn the crankshaft counterclockwise until the bar prevents further movement If none of the above methods is possible, take the engine to a repair shop or an authorized dealer service department and have them remove the nut for you. 7 Once the retaining nut is slackened, remove the clutch assembly as detailed in section 11. Now run the primary drive gear nut off the crankshaft threads, and remove the locking washer. Displace and remove the small pin which locates the oil feed quill in the crankshaft end, and place it with the quill. Remove the oil pump drive gear and the primary drive gear. Start by draining the disconnecting the clutch cable (if the engine is in the frame), then remove the right side crankcase cover For details, refer to Section 11.lt should be noted that the clutch must not be removed until the primary drive nut has been slackened. 2 Lift out the oil feed quill from the end of the crankshaft and put it in a container for safekeeping. Turn the crankshaft until the oil pump securing screws are visible through the holes in the outer cover Slacken and remove the screws (using an impact driver if necessary), then lift the pump away from the crankcase. 3 Remove the pump filter screen. Remove the single screw which retains the pump cover to the underside of the pump body. Lift away the cover, then tip out the pump rotors. The pump gear cover and gear can be removed for inspection. The cover is retained by two bolts. Wash the pump components in solvent, then when dry, store them together in a marked container. Inspection 8 Inspect the condition of the gear teeth, looking for chipping, breakage and general wear. Note that the primary drive gear teeth should be checked in conjunction with the corresponding teeth on the clutch outer, as described 9 Check the oil in section 11. pump body and Scoring indicates that rotors for scoring or other contaminated damage. has been circulating in the engine, and if this type of damage is found, disassemble the rest of the engine to check for other damage and clean out all oil passages, before fitting a new oil pump and reassembling the engine. 10 Fit the rotors into the oil pump body, then check the inner rotor to outer rotor clearance by measuring between the rotor tips with feeler gauges. Measure the gap between the outer rotor and the body in the same way Check the rotor to cover clearance (rotor end clearance) by placing a straightedge across the pump face and measuring between it dirty or oil Chapter 2 Engine and transmission 64 and the rotors with service limits, fit a feeler gauges. If the readings obtained exceed the new pump. Installation the pump gear shaft through its bore in the pump casing. Fit the gear over the shaft, then fit the gear cover and its retaining bolts. Fit the pump rotors into the pump body recess. Lubricate the rotors 1 2 with engine oil and check that they turn smoothly. Fit the pump cover using a new gasket. Fit and tighten the cover screw. Refit the oil pump pickup strainer. 13 Install the primary drive gear and oil pump drive gear on the crankshaft end Install the clutch assembly (Section 11). 14 Fit the oil feed quill locating pin through the hole in the crankshaft end. Place the lock washer over the crankshaft end with the 1 1 Fit pump 'OUTSIDE' marking visible. 15 Lock the primary gear and clutch outer to prevent the crankshaft from turning. Fit and tighten the retaining nut to the specified torque figure. Install the oil feed quill and spring, locating the quill over the locating pin in the end of the crankshaft. 16 Install the oil pump, using a new 0-ring in the pump outlet recess in the crankcase. Complete reassembly by refitting the right side cover and connecting and adjusting the clutch cable as described in Section 1 1 of this Chapter. 12.3a Remove the oil pickup filter for cleaning 12,14a Note 'OUTSIDE' marking on washer 12.14b Refit oil quill locating pin Fig. 2.10 Oil 1 2 3 4 Screw Cover Gasket Inner rotor 5 6 Pump body 7 Filter 8 Filter Outer rotor screen screen retainer pump (Sec 12) 9 0-ring 10 Locating pin 1 1 Screw - 3 off 12 Gear 13 Gear shaft 14 Gear cover 15 Bolt - 2 off Chapter 2 Engine and transmission 66 13 Gearshift linkage - Removal 1 The shaft removal, inspection and installation gearshift linkage can be worked on with the engine m the frame or on the workbench. Start by draining the engine oil and disconnecting the clutch cable, if the engine is in the frame. Remove the right side crankcase cover, the oil pump and the clutch assembly (see Sections 11 and 12). If this work is being undertaken prior to separating the crankcase 2 halves, slacken and remove the primary gear nut and remove the oil pump drive gear and the primary drive gear. For details, refer to Section 1 2. Note that the clutch should not be removed until the primary drive nut has been slackened. If still in place, release the external gearshift linkage from the left 3 side of the engine. 4 if bent, or if the claw ends are worn or deformed. and stopper arm roller for wear. Check the drum pins, stopper plate claw back against spring pressure towards the then slide the assembly out of its bore in the crankcase. Remove the selector drum stopper arm bolt and lift away the arm. Remove the drum stopper plate bolt. Lift away the plate and the Pull the gearshift Installation 8 Fit the drum pins into their holes in the end of the drum Place the stopper plate over the pins, making sure that they engage correctly. Note that the pins are positioned so that the plate will fit correctly in one position only. Install the stopper plate bolt and tighten it to the specified torque setting. 9 Place the stopper arm in position, checking that the spring is positioned properly. Fit and tighten the stopper arm bolt Make sure that the arm fits correctly over the shoulder on the bolt when tightening it. 10 Install the gearshift shaft assembly in the crankcase. Pull the claw back against spring pressure to allow it to fit over the end of the drum If nec^sary, turn the drum so that the claw clears the projections on the stopper plate Check that the centering spring locates over the pin the crankcase. shaft, in 5 6 Refit the external gearshift linkage and check that the gearshift assembly operates correctly Note that you may have to turn the gearbox sprocket to allow the gears to engage normally 12 Complete installation by fitting the primary and oil pump drive pinions (if removed), oil pump, clutch and the right side crankcase cover (Sections 11 and 12). drum pins. Inspection Check the 1 13 4 Pull gearshift shaft assembly for claw back to wear or damage. Renew the clear stopper plate during removal 11 13 5 Stopper arm is held by a single pivot bolt. Note spring end positions 13,6a Remove bolt and lift away the stopper plate^ 13 6b Lift out the pins and place them with the stopper plate Chapter 2 Engine and transmission 13.7 Check claw ends and spring condition 67 13.10 Install selector shaft. Note that ends of centering spring each side of locating pin in case fit on ® 0 Fig. 2.11 AC drum and 5 6 Bolt 3 Selector drum Neutral contact Pin - 4 off 7 Bolt 4 Stopper plate 8 Return spring 7 2 14 Selector generator and starter drive 9 Fork shaft 10 Left side fork 1 7 Center fork 12 Right side fork Stopper arm removal, inspection and installation Removal 1 Before work commences, note that you will need two special tools - a rotor holder (part number 07725-0040000) and a rotor puller (part number 07733-0020001 or gearshift shaft (Sec 13 and 14) 07933-21 60000). Commercially available versions of these tools are available from tool store or repair shops, and resourceful owners may be able to improvise their own tools. The AC 13 14 15 16 Gearshift shaft Centering spring Spring post Spring generator and starter drive can be worked on with the out of the frame. If the engine is installed in the frame, be sure to disconnect the battery (negative lead first) to isolate the electrical system before work commences. Disconnect the gearshift pedal linkage and remove the rear section of the left side crankcase cover (sprocket cover). Trace and disconnect the AC generator and ignition pickup wiring. 3 Remove the front section of the crankcase left side cover, lifting it away complete with the generator stator and wiring. Assemble the rotor holder according to the manufacturer's instructions and remove 2 engine in or Chapter 2 Engine and transmission 68 In the absence of the correct holding tool, a chain or strap wrench may be used provided care is taken not to damage the rotor. 4 Screw the rotor extractor into the large thread in the center of the rotor. Holding the rotor with the appropriate tool, tighten the extractor to draw the rotor off the end of the crankshaft. In the absence of the correct extractor it is possible to employ a large bolt of the correct diameter and thread. We used an old van wheel stud to good effect the rotor retaining bolt (photo). 5 Do not, however, attempt to use a legged puller. This will not apply pressure [O the center boss of the rotor and may cause damage to the rotor assembly. 6 Lift the rotor off the crankshaft and place it to one side with its retaining bolt and washer. 7 Remove the single bolt which retains the starter driven sprocket locating plate The starter chain and the drive and driven sprockets can now be slid off their respective shafts and placed to one side. 8 If required, the starter drive backing plate and dowel can be removed for inspection or cleaning. 9 The starter motor is retained by four bolts to the front of the crankcase and must be removed prior to crankcase separation. 10 The AC generator stator assembly and the ignition pickup are housed inside the outer cover and need not be disturbed unless renewal is necessary. The stator is retained by three screws and the pickup coil by two screws. Note the position of the wiring grommets so that they may be correctly refitted when installing the assembly. 14 4 Van wheel studs make instant home-made extractor! Inspection 1 1 Check the teeth of the starter drive and driven sprockets for wear or damage. If necessary, renew the chain and both sprockets to restore normal operation. 1 2 Check the oil seal at the center of the driven sprocket for damage. If renewal is required, lever out the old seal, then press in the new one using a large socket against the outer edge of the seal. Check that the seal enters the sprocket bore squarely, and apply some molybdenum disulfide grease to the seal lip. 13 Measure the inside and outside diameters of the driven sprocket boss. If either dimension is outside the service limit, renew the sprocket. 14 If starter engagement problems have been noted, or if the outside diameter of the driven sprocket boss is scored or badly worn, disassemble the starter clutch to check for wear or damage. Use a small screwdriver or a scriber to prise out the clutch rollers, then remove the spring caps and springs. If these are worn or damaged, renew them. 15 Release the starter clutch cover screws, using an impact driver if necessary. Do not strike the rotor with a hammer or it may become partially demagnetised. Lift off the cover, the clutch body and the side plate. Check the clutch body for wear, looking for indenting or scoring of the roller slots Renew the body if wear is found. 14.6a Release bolt and lift away sprocket guide Installation Assemble the 1 6 starter clutch by reversing the disassembly sequence. Note that if a new rotor is to be fitted, the clutch locating dowel must be transferred from the old rotor. Check that the clutch side plate and the clutch body engage over the locating dowel during installation. Use the clutch screws and use a locking agent on the threads. Tighten the screws to the specified torque setting. 17 Using a small screwdriver and a good deal of patience, fit the clutch springs and caps, then work each of the rollers into position. Temporarily fit the driven sprocket into the clutch and check that the clutch operates smoothly. If fitting proves difficult, try turning the sprocket slightly as it fits into the clutch. 18 Refit the starter motor. Stick a new gasket onto each side of the starter drive backing plate using gasket compound. Check that the dowels are in place, then position the backing plate on the crankcase. Fit the sprockets and chain, then fit the driven sprocket locating plate and bolt. Fit the AC generator rotor and tighten its retaining bolt to the specified torque setting. 19 Complete installation of the left side crankcase covers by reversing the removal sequence. Check that the wiring grommets are positioned correctly and that the wiring is connected properly before reconnecting the battery leads. Start normally. and run the engine to check that it operates 14.6b Chain and sprockets can be lifted away plate p 14.8 Remove backing plate and dowels 14.14b Plungers and springs can 14.18b Install chain, now for cleaning, if required be removed from hub sprockets and sprocket guide plate 14 14a Use scriber to pry out the clutch J 4.1 8a Use new rollers gasket on each side of the backing plate 14 19a Check that locating pin is in place on crankshaft taper Fig. 2.12 7 Bolt 2 Washer 3 4 Generator rotor Dowel AC generator rotor and starter drive (Sec 14) Backing plate 9 10 Screw - 3 off 7 Spring - 3 off Spring cap - 3 off 8 Roller - 5 6 3 off 11 Starter clutcf) Oil seal 12 Starter driven sprocket 13 Sprocket locating plate 14 Bolt 15 Drive chain 16 Starter drive sprocket Chapter 2 Engine and transmission 15 Crankcase - disassembly and reassembly Disassembly To gain access to the crankshaft, the transmission shafts and gears, drum and forks and the cam chain tensioner assembly, the crankcase halves must be separated. Before separation can be carried out, the following components and assemblies must be removed: 1 the selector engine from the frame (Section 4), camshaft (Section 6), cylinder head (Section 7), cylinder block (Section 9), pistons (Section 10), clutch (Section 11), primary drive gear and oil pump (Section 12), gearshift linkage (Section 13), and AC generator and starter drive (Section 14). 2 The crankcase halves are secured by a total of ten bolts, two of which are fitted from the left side of the unit. Slacken and remove the two bolts first, then turn the engine over and support it on blocks with the right side facing upwards. Slacken the eight remaining bolts in stages. Once all the bolts are 3 loose, run them out of their threads. To speed up reassembly, draw the outline of the crankcase on a piece of card and push each bolt through the card at the appropriate position. 4 The crankcase halves are now ready for separation, but will probably be stuck firmly together by the gasket compound on the mating faces. To help break the seal between the two cases, tap around the joint with a soft-faced hammer, or use a hardwood block and a metal hammer, if the joint fails to separate at one point, check that no fasteners have been overlooked. Never apply excessive force if the case 71 14 Fit the dowel pins into the holes in the left case, and place a new gasket in position. Lower the right case half over the left case half. Tap the case down with the palm of the hand until the gasket faces touch. Do not use force if the right case will not contact the left case, remove and check that the transmission shafts, selector drum and selector it fork shaft are positioned correctly. 15 Fit the eight retaining bolts and tighten them down progressively and in stages to avoid warping the cases. No torque figure is specified, but try to tighten the bolts evenly and securely. Turn the engine over and fit and tighten the remaining bolts 1 6 At this stage, check that the transmission shafts and the crankshaft can be turned normally. If any shaft seems stiff when turned, it may not be seated correctly. Disassemble the case halves and correct this before proceeding further. 17 Complete reassembly by refitting the external components and assemblies in the reverse order of removal. seem unduly tight. Use the reinforced pry point on the underside halves of the crankcase to the seal has broken, lift the right crankcase half upwards, leaving the internal shafts in place in the left half. 6 Pull out the selector fork shaft, leaving the forks engaged in the 5 aid separation. gear grooves. Once Remove each fork in turn and fit it on the shaft in its correct position. Lift out the selector drum. 7 Lift out the transmission mainshaft and countershaft assemblies and place them with the selector forks, shaft and drum to together, await inspection. 8 The crankshaft assembly is retained in the crankcase left side case by five bolts and a nut These pass through the center mam bearing block. Remove the bolts and nut, then lift the crankshaft out of the case. Leave the cam chain and tensioner attached to the crankshaft at this stage and place the assembly to one side. Reassembly 9 Reassembly should not commence until all crankcase components, including bearings and seals, have been checked. The cases should be thoroughly cleaned by steam or pressure washing, or using solvent, and should be dry Remove the neutral switch prior to cleaning the crankcases. It is located in the center of the left casing and is retained by a bolt and retaining plate. Check that all traces of gasket and gasket compound are removed from the gasket surfaces. Be careful not to scratch or gouge the gasket surface or oil leaks will result. It is advisable to use a gasket removal product to help with this task. This is available in spray can form from most auto accessory stores and repair shops. 10 Install the crankshaft, complete with cam chain and tensioner, into the crankcase left half. Note that wood blocks must be placed under the case to allow the shaft end to protrude through the bearing. Fit the center bearing block bolts and nut and tighten them to the specified torque figure. Install the cam chain guide blade in the center bearing block hole. 11 Coat the transmission gear shafts with engine oil and check that they turn smoothly. Fit the two shafts together with the gear teeth meshed, and install the shafts into the case. 12 Fit the selector drum into, the case, aligning the neutral switch contact blade with the tip of the neutral switch. 13 Fit each selector fork into its groove in the appropriate gear, and position the guide pin in the selector drum groove. It may be necessary to lift the gear(s) a little so that the guide pin can be located. Align the selector fork bores and slide the shaft through them. Check that the gear shafts turn smoothly and that the selector mechanism operates correctly. 15.10a Install 15.10b Fit the crankshaft assembly into the left crankcase half and tighten the crankshaft retaining bolts and nut 15.10c Install 15.13a Fit the cam chain guide in center bearing block hole the selector forks into the transmission gear grooves 15.13c Slide the selector fork shaft through' the. forks 1 5.1 1 Fit 15.13b 15.14a the transmission shafts as a pair Install Fit the selector drum and engage crankcase dowels and a new fork pins gasket 73 Chapter 2 Engine and transmission 15.14b Lower the crankcase right half over the assembled left half 16 Crankcase and bearings - inspection Once the crankcase halves have been separated and the transmission shafts, selector drum, selector forks, neutral switch and crankshaft 1 have been removed, the cases should be thoroughly cleaned by steam washing, or by using a solvent. Use brushes to clean out any recesses or oil passages. 2 The cleaned cases should be dried, preferably by using compressed air. The oil passages should be blown through with compressed air or cleaned with oil line brushes to remove any residual oil or solvents. 3 Check that all traces of gasket and gasket compound are removed from the gasket surfaces. Be careful not to scratch or gouge the gasket surface or oil leaks will result. It is advisable to use a gasket removal product to help with this task. This is available in spray can form from most auto accessory stores and repair shops. 4 Check both cases for signs of damage such as cracking. If serious, cracks will mean a new pair of cases. Less serious damage can be repaired by welding, but this is a professional repair operation. Consult an authorized dealer service department or repair shop who may be able to carry out the repair work or suggest a reliable repairer. 5 Damaged threads or broken off screws and bolts should be dealt with at the same time. Once again this is specialised work outside the scope of the average home workshop. 6 Once the general condition of the cases has been checked, attention can be turned to the various bearings and crankcase fittings. Note that some or all of these will have to be removed before any repair work on the cases is undertaken. Start by removing the oil through plate from the inside of the left case. This is secured by three screws which should be released using an impact driver. 7 The oil seals should be renewed each time the cases are separated, and should have been purchased along with the gasket set. Check that you have all the seals and that each one is the right size and type. 8 Check each of the bearings by turning them by hand. A worn or damaged bearing will usually feel coarse or gritty when turned, and any bearing which does not move smoothly and easily requires or pressure 15.15 Carefully trim off excess gasket at cylinder joint face bearing remover will be needed. These can be obtained from tool stores. 11 Heat the crankcase evenly to 212°F (100°C) in an oven, or by immersing the case in boiling water. Never use a torch or other form of localised heat, or the case may be distorted and ruined. Take suitable precautions to avoid burns, making sure that the arms are covered and that heat-resistant gloves are worn. 12 Support the area around the bearing boss with wood blocks to minimise the stress on the castings. Tap out the old bearing using a socket as a drift against the outer race. Alternatively, assemble the bearing remover and drive it out of the case. 13 Re-heat the case as required, then tap the new bearing into its bore, driving on the outer race only. Make sure that the bearing is fitted facing in the right direction, and that it enters its bore squarely and fully. Grease the lip of the new oil seal (where fitted) and press this into the bore. When fitting the countershaft oil seal do not position its outer face below the outside of the crankcase because this will block the countershaft oil way Refit any circlip or retainer removed during the overhaul. through plate to the inside face of the left case. First, fit O-ring to the case recess, then place the plate in position. Use thread locking compound on the retaining screws. 1 a 4 Refit the oil new renewal. Before proceeding, check that a new bearing of the correct type is fitted. Make a note of any numbering on the bearing race - it is essential that the new bearing is fitted so that it faces in the same direction as the old one. 10 The procedure for bearing renewal is dependent on the location and whether the bearing is retained in some way. In some instances the bearing is simply pressed into a recess in the case, while in others a circlip or retainer plate may be used to secure the bearing after it has been fitted. Start by removing any retainer or circlip as required. Note that where a bearing is fitted into a blind hole, a slide hammer type 9 available, together with a new oil seal, where 16.10a Check bearings for wear or damage Chapter 2 Engine and transmission 74 isr J 16 10b Blind bearings like this one require a slide hammer type 16.13a Lever out the old seals with a screwdriver oil extractor 16 13b Tap the new seals into place using a large socket 16 14a Fit a new oil through plate 0-nng 17 Selector forks and drum - inspection 1 To gain access to the selector drum and crankcase halves as described in Section 15. forks, separate the Examine the selector forks for wear and damage. Look for damage 2 on the fork ends which engage in the transmission gear grooves. If these are bent or badly scored, the fork must be renewed. Measure the thickness of the fork ends and the fork bore inside 3 diameter If worn beyond the service limit in either area, renew the fork. Check the pins which engage in the selector drum tracks. If these are badly worn, the fork should be renewed. Alternatively, an engineering shop may be able to build up the worn pin by welding, and re-machine It to 4 like its original dimensions. Check that the fork shaft a sheet of glass, and is not bent by placing rolling it. it on a flat surface, Any bending should be easily detected. If it is worn beyond the renew the shaft. 6 Check the grooves in the selector drum for wear or damage, paying particular attention to the high spots which will wear down quickest. If badly worn, the drum should be renewed. 5 Measure the outside diameter service limit at any point along 16,14b Install the oil through plate and fit the retaining screws its of the shaft. length, Chapter 2 Engine and transmission 75 18 Transmission gears and shafts - disassembly, inspection and reassembly 1 To gain access to the transmission gears and shafts, separate the crankcase halves as described in Section 1 5. To carry out disassembly and reassembly of the shafts you will need a pair of circlip (snap rmg) pliers. It is preferable to fit new circlips during reassembly, and these should be ordered in advance. Commence disassembly with the countershaft (output shaft). 2 Remove the thrust washer from the right end of the shaft, then lift away the 1st gear and its headed bush. 3 Now remove the 3rd gear, placing it in sequence on top of the 1st gear. Using circlip pliers, open the circlip just enough to allow it to be slid off the shaft. Remove the splined washer, the 4th gear and the 5th gear. 17.2 Check the selector forks and shaft for wear and damage Fig. 2.13 1 2 3 4 5 6 Mainshaft with 1st gear Mainshaft right side bearing Mainshaft 3rd gear Splined thrust washer -2 off Circlip - 2 off Mainshaft 4th gear 4 Note that the 2nd gear should be considered integral with the shaft and should not be removed Place the disassembled shaft and gears in a marked container to keep them separate from the mamshaft components. 5 Moving to the mainshaft (input shaft), remove the thrust washer from the left end of the shaft assembly, followed by the 2nd and 5th gear. Slide off the splined washer, then remove the circlip and 4th gear. Remove the next circlip, the second splined washer and 3rd gear. The Transmission shafts (Sec 18) Mainshaft 5th gear Mainshaft 2nd gear Thrust washer 10 Mainshaft left side bearing 1 1 Countershaft with 2nd gear 12 Countershaft left side 7 8 9 bearing 13 14 15 16 17 18 Oil seal 19 Bushing Countershaft 5th gear Countershaft 4th gear Splined thrust washer 20 Countershaft Circlip Countershaft 3rd gear 1st gear 21 Thrust washer 22 Final drive sprocket 23 Retainer 24 Bolt - 2 off Chapter 2 Engine and transmission 76 is machined into the mainshaft and thus cannot be removed. Examine each gear in turn, checking for wear and chipped teeth. If damage is found, check for corresponding damage on the corresponding gear of the other shaft. Always renew the gears as a pair 7 Check also the engagement dogs and holes on the sides of the gears. If these become badly worn or rounded, there may be a tendency for the machine to jump out of gear in use. The affected gear(s) should be renewed. 8 Measure the inside diameter of the countershaft 1st and 4th gears and the mainshaft 5th gear and compare it with the specified figure. Renew any gear which is worn beyond the service limit. 9 Measure the inside and outside diameter of the countershaft 1st gear bush. Renew it if it is worn beyond the service limit. 10 Measure the outside diameter of the countershaft at the point where the 1 st gear and the 4th gear run. Renew the shaft if worn down 1st gear 6 to the service limit. 1 1 Measure the outside diameter the service where worn down to of the mainshaft at the point the 5th gear and the clutch outer run. Renew the shaft if limit. 12 Reassemble the shafts using new circlips. These should be fitted carefully, avoiding spreading the clip any more than necessary to work it over the shaft. Lubricate each gear with engine oil during fitting. Study the accompanying photographic sequence and illustration for a guide to the reassembly sequence. 18.12a Countershaft 2nd gear cannot be removed from shaft 18.12b Fit countershaft 5th gear with dogs towards 2nd gear 18.12c 4th gear 2d Fit a splined thrust 18.1 washer ... 18.12e ... is fitted with groove inwards and secure the assembly with a circiip 18 12) Mainshaft 1st gear is machined into the shaft 18,12k Install the 3rd gear as shown 18.121 Fit a 18.12n Fit 18.12p ... splined washer 18 12m ... 4th gear with selector groove inwards and then slide a thrust washer over shaft ... and secure with a circlip 18.12o Install a circlip in shaft 18 12q Fit the 5th gear ... groove as shown ... Chapter 2 Engine and transmission 79 noise was evident during running, or the chain is obviously loose or worn, it should be renewed. 6 Check that the tensioner operates smoothly with no sign of sticking. Check the locking action of the lower wedge. Installation 1 Check that the center bearing block correctly (see diagram), then place the on the crankshaft is positioned cam chain loop around its drive sprocket. 8 Fit the tensioner on its support pin. Fit the plain washer, then insert the locking pin. 20 Crankshaft - inspection for inspection or renewal requires its Section 15. For an accurate check of crankshaft condition, you will need feeler gauges, V-blocks and a dial gauge. In the absence of the necessary equipment, you may choose to have the measuring work carried out by an authorized dealer service department or a repair shop. 2 Check the side clearance of each connecting rod by inserting feeler gauges between the rod big end and the crankshaft. A certain amount of side-to-side movement is necessary here, but if it exceeds the service limit, the crankshaft will require attention. 3 Set up the crankshaft between V-blocks, then assemble the dial gauge and stand so that the big end bearing radial play can be checked. Measure any movement in line with the connecting rod and at 90° to it. If this exceeds the service limit, worn big end bearings are Access to the crankshaft 1 removal as detailed 18.12r 19 ... Cam and the 2nd gear, followed by a thrust washer chain and tensioner - removal, inspection and installation in indicated. inspection requires the removal of the crankshaft as detailed 4 Move the dial gauge assembly to the ends of the crankshaft and check for runout by turning the crankshaft. The measurement point is 39.5 mm (1 .56 in) out from the outer flywheel face on the right side. On the left side, the measurement point is 55.0 mm (2.17 in) out from 15. the outer flywheel face. Removal 1 Access to the cam chain and tensioner mechanism for renewal or in Section • With the crankshaft on the workbench, pull out the lock pin and slide the plain washer and the tensioner assembly off its support pin on 2 the center bearing block. 3 Position the bearing block in relation to the crankshaft balance weights as shown in the accompanying diagram. The cam chain can now be disengaged from its drive sprocket and removed. Inspection 4 Check the working surface of the tensioner blade and the cam chain guide blade for wear or damage. If deeply grooved or if the surface is showing sign of disintegration, renew the tensioner and the guide. 5 No service limit figures are available for the 19.2 Tensioner blade is retained by lock pin cam chain, but and washer if chain Check the runout at the crankshaft center by resting the dial gauge probe on the center bearing block. Hold the block to stop it turning, and rotate the crankshaft. If the crankshaft is outside the service limits in any of the above 6 checks, or if the big end or center main bearings are obviously worn or damaged, the crankshaft assembly will have to be renewed. The crankshaft is available only as an assembly, and therefore cannot normally be overhauled. 7 The only possible alternative to renewal is to find an engineering shop which will undertake the reconditioning work. This is a possibility which will have to be investigated on a local basis, and your local dealer service department or repair shop may be able to offer advise on this point. 5 19.3 Position center bearing block and crankshaft as shown, then disengage the cam chain Chapter 2 Engine and transmission 80 19.5 If crankshaft sprocket teeth are damaged, a new crankshaft will be needed Fig. 2.14 TENSIONER PIN H 20055 CRANK WEIGHT BALANCER Fig. 2.15 Correct crankshaft position for cam chain removal and installation (Sec 19) chain and tensioner (Sec 19) Bolt - 2 off Camshaft sprocket Cam chain Guide blade Tensioner Bolt - 2 off 1 2 3 4 5 6 21 Cam 7 Washer 2 off 8 9 Spring Spring sleeve 70 R-pin 1 7 Washer start-up after major repair Initial Note; Before attemptmg to start an overhauled or repaired engine, engine adjustments and settings are correct. For details, refer to the appropriate parts of Chapter 7. In particular, the valve clearances and spark plugs should be checked, and the engine oil should be topped up to the correct level. make sure that all 1 Temporarily remove the spark plug caps and spark plugs. Set the engine stop switch to 'OFF', then switch on the ignition and crank the engine for 1 0 to 1 5 seconds. Refit the plugs and plug caps, and set the engine stop switch to 'ON', 2 Check that there is fuel in the tank, and set the petcock to the 'ON' or 'RES' position as appropriate. Wait a few seconds to allow the float bowl to fill. Set the choke control to 'ON'. Switch on the ignition and check that the transmission 3 neutral. Operate the seconds of cranking, leave starter. it If the engine for a fails is shifted to to start after a few seconds, then attempt few to start it again. 4 check that fuel is reaching the carburetor (see and 3) and that the plugs are sparking normally (see 1 and 4). 5 Once the engine starts, allow it to run at a moderately fast idle for a few minutes to reach normal operating temperature During this time, check around the engine closely for signs of leaks. 6 Before test riding the machine, check the operation and adjustment of all controls, especially the brakes, clutch and throttle. Refer to the following section for information on the correct break-in procedure. If it still Chapters Chapters 22 1 fails to start, 1 Recommended break-in procedure After major engine work involving the fitting of 20.2 Check gauges th( iM] rod big end side clearance with feeler new parts such as important that the new parts are allowed to wear in a controlled fashion to other parts with which they are in contact. The process is known as break- in and applies as much to an overhauled engine as to a new one. piston rings, a crankshaft or transmission parts it is Chapter 2 Engine and transmission 2 The general principle is to allow the engine to spin freely under it or allowing it to run at not allow the engine to lug at loadings, but without over revving light constant speed for any length of time. Do low speeds with large throttle openings, or to idle for long periods. 3 The break- in procedure should be followed for at least 600 miles (1000 km). When this point is reached, carry out an initial service (see Chapter 1 ). In particular, be sure to carry out an oil change to remove the small metal particles which will be carried into the oil system during Fig. 2.16 1 2 3 4 5 6 Crankshaft Piston - 2 off Piston pin - 2 off Circlip - 4 off Piston ring set - 2 off Locating pin Neglecting or postponing the initial service will cause premature engine wear. 4 After the 600 mile mark, gradually increase engine speeds and loadings until normal use is resumed. The length of this second stage is discretionary, the point being to gradually increase pressure on the engine, rather than suddenly. As a rough guide, consider the engine fully broken-in after about 1000 miles. break-in. Crankshaft and pistons (Sec 20) 7 Right side main bearing 8 9 Bolt - 5 off Stud 70 Nut Primary drive gear 12 Oil pump drive gear 11 13 14 15 16 17 Locking washer Nut Spring Oil feed quill Locating pin 39.5 mm (1.56in) Fig. 2.17 Measuring big end bearing 81 radial play (Sec 20) Fig. 2.18 18 Oil through plate 19 Screw - 3 off 20 0-ring 21 Left side main bearing 22 Oil seal mm 55. 0 (2.17in) Measuring crankshaft runout (Sec 20) 1 Chapter 3 Fuel system Contents General description Fuel tank - removal and installation Carburetor overhaul - general information Carburetor - removal and installation Accelerator pump - disassembly, inspection and reassembly Carburetor vacuum chamber - disassembly, inspection and reassembly 1 2 3 4 5 6 Carburetor float bowl components - disassembly, inspection and reassembly Float height - check and adjustment Pilot screw - adjustment High altitude adjustment - general information Air cleaner assembly - removal and installation Crankcase breather separator removal, cleaning and installation Purge control valve - inspection (California models) Specifications Carburetor Make number: 49 State model California model Keihin Identification Venturi diameter VEOSA VEISA mm (1.00 ± .0 Float height 25.2 18.5 Main jet number: 1985 model 1986 on models Slow jet number Idle speed Pilot screw initial setting 135 128 35 1300 ± 100 rpm 2^4 turns out Throttle grip free play 1 2-6 mm mm in) (0.73 (Vs - in) Fuel tank Capacity: Overall 2 8 Reserve 0.6 US US gal (10.5 gal (2.5 liter) liter) ± 0.04 in) 7 8 9 10 1 12 13 Chapter 3 Fuel system 1 work area system comprises the fuel tank, petcock, carburetor and air Gasoline is fed via the manual petcock to the carburetor float bowl Here, the carburetor jets atomise and meter the fuel mixing it with air drawn in through the air cleaner assembly. The resulting mixture is then delivered to the engine by way of the intake fuel cleaner assembly. and valve. The various carburetor jet sizes and the position of the throttle valve determine the volume and strength of the mixture at various engine speeds and loads. In addition, there is an accelerator pump which provides temporary richening of the mixture under acceleration. The pump allows the general mixture strength to be set leaner, and thus ensures good fuel economy and minimum exhaust emission levels. The carburetor is also equipped with a manually operated port bypass-type cold body is start (choke) system A plunger controlled by a handlebar lever and cable. raised, the cold-start circuit necessary for the drawn initial is the carburetor in When the plunger is opened, providing the fuel-rich mixture start-up from cold engine through the air cleaner. The air cleaner case ensures that the incoming air is drawn in well away from most road dust and water. It then passes through an air filter to remove any remaining contaminants. The filter is made from porous foam sheet, impregnated with oil to catch dust particles. To limit air pollution a crankcase emission control system is fitted. A breather hose from the crankcase passes through a separator in which most of the oil vapor condenses into a drain tube. The drain tube has a removable plug to allow periodic draining. Remaining oil vapor is drawn into the intake system and passed through the engine, where it IS burnt along with the normal fuel For California market models, an evaporative emission control system is fitted When the machine is parked, any fuel vapor vented from the fuel tank due to temperature fluctuations is passed to a charcoal canister for storage. When the engine is next started, a vacuum-operated purge control valve opens, allowing the stored fuel to be drawn through the carburetor and burnt. The system minimises the venting of unburnt hydrocarbons direct to the atmosphere. The intake system, along with the exhaust system, form part of the noise emission control system as required by Federal law. Note that removing, tampering with or modifying parts of the machine which affect either noise or hydrocarbon and carbon monoxide emission, may Air is into the one or more EPA or CARB laws. For full details of local legal requirements, consult the relevant local enforcement agency. violate 2 commences, ensure that nobody in the smoking, and that there are no sources of flames or bare light bulbs present. Do not work in any building containing a gas appliance with a pilot light Gasoline vapor is heavier than air and will collect in poorly ventilated corners of buildings Avoid getting gasoline in the eyes or mouth, and try to avoid skin contact In case of accidents, flush the affected area with copious quanties of water and seek prompt medical advice. the fuel system Before work General information The Fuel tank - removal and installation is Remove two bolts at the rear of the passenger seat. Lift the back and pull it rearwards to disengage the front mounting. Repeat the above procedure to remove the rider s seat Remove the single bolt at the rear of the tank, and the two front 2 bolts which are located on each side of the steering head. 3 Check that the petcock is turned to the OFF' position. Disconnect the fuel line by squeezing together the ends of the retaining clip and sliding it along the line. Use a small screwdriver to work the line off the 1 the of the seat petcock stub. 4 On California market models, the vent pipe from the underside of the tank must be disconnected. This is done in the same way as described for the fuel line. Lift the tank up and back, taking care to avoid paint damage. Place 5 the tank on some soft cloth until it is required. 6 The tank is installed by reversing the above procedure Check that the vent pipe (where applicable) and the fuel line are fitted correctly and that the clip is slid back over the stub to secure them. Turn the petcock to the ON' or RES' positions and check carburetor overhaul must be determined on an based on the symptoms noted. As a general indication, poor engine performance and fuel economy, erratic throttle response and little or no response to idle mixture adjustment, point to the need for overhaul. 1 The need individual for basis, 2 Do not consider the carburetor as a discrete component. Its operation is affected by the condition of the air cleaner and exhaust system, and other engine faults such as, incorrect valve clearances, worn or fouled spark plugs or fuel contamination. Faults in these components can often be inadvertently attributed to the carburetor. Check these areas before overhauling the carburetor. Most carburetor problems are caused by water, dirt or varnish 3 deposits in the fuel passages and jets Other problems can arise due to air or fuel leaks caused by worn or shrunk gaskets and 0-rings. 4 Before commencing the overhaul, purchase a rebuild kit containing all the 0-rings, gaskets and other parts liable to wear or deterioration. The carburetor can then be dismantled, cleaned, checked and then without any risk of extremely flammable, particularly when in the form of vapor Precautions must be taken when working on any part of formulated to remove 2.5a Petcock can be detached after fuel tank has been 2.5b is removed for fuel leaks. Carburetor overhaul - general information 3 rebuilt Warning: Gasoline 83 It IS subsequent leaks or undetected seal failures. also worth purchasing a spray can of carburetor cleaner. This If tank is dirt and varnish deposits quickly and to be flushed out, is effectively. disassemble the petcock and clean it Chapter 3 Fuel system 84 4 Carburetor - removal and installation Warning: Gasoline is extremely tiammable. particularly when m the lorm ol vapor. Precautions must be taken when working on any part ol the luel system. Before work commences, ensure that nobody in the work area is smoking, and that there are no sources of flames or bare light bulbs present Do not work in any building containing a gas appliance with a pilot light Gasoline vapor is heavier than air and will Avoid getting gasoline eyes or mouth, and try to avoid skin contact In case of accidents, flush the affected area with copious quantities of water and seek prompt medical advice collect in poorly ventilated corners of buildings 5 Check the pump stroke adjustment as follows. Back off the throttle stop screw until the butterfly valve is fully closed Measure the gap between the adjusting arm and the pump rod If this exceeds the zero clearance specified, adjust the clearance by carefully bending the end of the arm. Measure the clearance between the adjusting arm and the carburetor body stop; this should be 6.5 (0.26 in). If adjustment is required carefully bend the end of the arm 6 Install the carburetor (Section 4) and check all adjustments (Chapter 1). Note that the throttle stop screw must be reset to its mm normal position. in the Removal 6 Carburetor vacuum chamber and reassembly Remove the passenger s and rider s seats and remove the fuel tank (Section 2). Note that carburetor removal and installation can be performed with the fuel tank in position, but access is severely limited, Note? Before proceeding, refer to the warnings given concerning gasoline. - disassembly, inspection 1 and there is some risk of paint damage If the fuel tank has not been removed, turn the petcock to OFF and 2 disconnect the fuel line Trace the float bowl drain hose and place a container below its end Slacken the drain screw at the base of the float bowl (left side) and allow the fuel in the float bowl to drain into a metal container Tighten the drain screw Make a simple sketch of the carburetor vent, breather and drain 3 hoses to act as a guide during installation. You may wish to mark the end of each hose with masking tape as an aid to identification. 4 Remove the pulley cover, slacken fully the throttle cable lower adjusters and disengage both cables from the bracket and pulley. Pull back the rubber boot at the bottom of the cold start (choke) cable Unscrew the cold start plunger and withdraw it from the carburetor body Tie the cables clear of the carburetor. 5 Slacken the clips which retain the carburetor to the air cleaner connector and to the intake adaptor. Pull the carburetor body back against the air cleaner case until the intake stub clears the adaptor Twist the carburetor until it can be pulled clear of the adaptor and removed. Installation 6 The carburetor is installed by reversing the removal procedure. held vertically between the intake and air cleaner adaptors, then secure the retaining clips Install the cold start plunger assembly and the throttle cables. Check the cable adjustment (Chapter Check that it is 1). Reconnect the dram, vent and breather pipes, following the sketch removal. Refit the fuel tank and turn the petcock to the 'ON' or RES' position. Check for leaks. If the carburetor was dismantled, check the idle speed and mixture settings (Chapter 1) 7 made during Accelerator reassembly 5 pump - disassembly, inspection Note: Belore proceeding, concerning gasoline. refer to the Disassembly Remove the four screws which retain Carefully lift away the cover and spring, 1 in Section 4 the vacuum chamber cover taking care not to tear the diaphragm. If it is stuck to the cover, gently peel it away. Remove the cover and vacuum piston spring. Lift the diaphragm edge away from the carburetor body. Once free, 2 withdraw the diaphragm and vacuum piston assembly. 3 To free the needle holder from inside the piston, depress the needle holder with an 8 holder, spring mm socket, then twist it through 60° Remove Inspection 4 Check the needle bending. Check the diaphragm for scored or bent it is likely that the needle jet will also be damaged (see Section 7). Check the condition of the vacuum piston and the bore in which it runs If either or both parts are scored or distorted, air leakage or sticking may occur. If badly worn, or if the piston sticks in its bore, renew the piston assembly. splits or holes. If for scoring or the needle is Reassembly 5 Install the vacuum chamber components by reversing the disassembly sequence. When fitting the diaphragm, check that the tab on its edge locates in the cutout in the carburetor body and that the edge of the diaphragm locates correctly If the diaphragm cannot be refitted, Honda recommend that it should be allowed to dry out fully and then installed. Fit the vacuum chamber cover, being sure not to move diaphragm. and warnings given in Section 4 Disassembly Release the three screws which retain the accelerator pump 1 diaphragm cover. Carefully lift away the cover, taking care to avoid tearing the diaphragm which may adhere to the carburetor body and/or the cover. If this occurs, carefully peel the edge of the diaphragm off the surface to which it is sticking. Remove the diaphragm and pump rod assembly, the spring and the 2 rubber boot. Inspection Check the diaphragm for splits or pin holes. Check the rubber boot 3 for similar damage. Check the pump rod for scoring or bending. If any damage is found, renew the pump rod and diaphragm, the rubber boot pump cover as an assembly. Note that these parts are not supplied separately. and the Reassembly 4 the pump parts pump mechanism Install that the the reverse order of disassembly. Check operates smoothly. in the and needle. 4.4 Release the throttle and choke cables. Disconnect dram and breather hoses the 6.1 Remove the vacuum chamber cover and spring 6.2 Peel away the diaphragm and remove valve assembly Fig. 3.1 7 Throttle cable bracket 11 Needle jet holder Screw - 4 off Vacuum cfiamber cover 12 13 14 15 16 17 18 19 2 3 4 5 6 Jet needle 7 Diaphragm and piston 8 Fuel pipe Spring Needle 9 Clip 10 Needle fiolder jet 20 Main Slow jet Pilot screw jet Spring Washer 0-ring Float Float valve Float pivot pin Carburetor (Sec 5, 6 and 7) 21 0-ring 22 23 24 25 26 27 28 29 30 0-ring Float bowl Screw - 4 off Drain screw 0-ring Overflow hose _ Clip Throttle stop Accelerator screw pump 31 32 33 34 35 36 37 Choke plunger Rubber cover Adjusting arm retainer Throttle link Throttle pulley cover Screw - 2 off Emission control hoses California - state A 49 models only models only Chapter 3 Fuel system 7 Carburetor float bowl components - disassembly. Inspection and reassembly Note: Before proceeding, concerning gasoline refer to ttie warnings given in Section 4 in the float bowl has been drained which secure the float bowl to -the underside of the carburetor body and lift it away. Displace the float pivot pin, and lift away the float and float valve 2 3 Remove the cheese-headed mam jet, then unscrew thg needle jet holder, located directly beneath the main jet. Invert the carburetor and tip out the needle jet. Note that it is small and easily lost - place the removed jets in a clean container to avoid loss. 4 Unscrew the slow jet from the recess adjacent to the main jet bore. 5 Turn the pilot screw clockwise until it seats lightly, counting the number of turns and part turns so that it can be refitted in the original position. Make a note of the setting and then unscrew and remove the 1 Check pilot that Remove any residual fuel the four screws screw. Inspection 6 Carefully clean the carburetor parts in solvent and blow them dry with compressed air. A carburetor cleaner can be used to good effect to remove varnish deposits from the carburetor body but check that it is safe to use on the plastic parts and seals, or remove them before cleaning. 7.1 Float bowl is secured by four screws . 7.2b Remove Note that the jets must not be cleaned by pushing wire through 7 them, the wire will damage the jet drillings and upset the mixture strength. If blocked with sludge or dirt, clean with compressed air, or as a last resort, use a fine nylon bristle from a brush to clear the obstruction. If examination of the vacuum chamber parts revealed needle wear (Section 6), check the condition of the needle jet. It is advisable to renew the needle and needle jet as a pair 9 Check the fuel inlet (float) valve for wear at the tip If this is scored 8 Disassembly fully. 87 s or ridged, fit a new valve. 10 Check the float for leaks or other damage. Renew the float if it is found to be defective 1 1 Check the end of the cold-start plunger for wear If it is indented or split, renew it. Reassembly 12 Reassemble the float bowl parts by reversing the disassembly sequence. Use new gaskets and 0-rings throughout Be sure not to omit the needle jet when fitting the needle jet holder. 13 Before refitting the float bowl, check the float height setting as described in section 8 14 Refit the pilot screw until it just seats, then back it out by the number of turns or part turns noted during removal. Check the pilot mixture screw adjustment as described in Section 9, If a new pilot screw IS being fitted, fit a new limiter cap, using Loctite 601 or equivalent to retain it. The tab on the limiter cap must be positioned so that further counterclockwise movement is prevented 7.2a Push out the float pivot pin to release the float • the float valve for inspection 7.3a Unscrew mam jet from needle jet holder Chapter 3 Fuel system 88 8 Float height - check and adjustment Note: Before proceeding, concerning gasoline refer to tfie warnings given m Stclion 4 If the carburetor has been overhauled, or if flooding or starvation problems have been noted, the float height should be checked. Start by removing the carburetor and removing the float bowl as described in the preceding sections. 1 2 The measurement required is the distance between the carburetor gasket face and the bottom face of the float A special gauge is available from an authorized dealer service department, but the check can be carried out using a rule or vernier caliper if care is taken. 3 Hold the carburetor on its side so that the float hangs from its pivot Slowly turn the body so that the float tang just contacts the end of the float -^/alve (it must not compress the valve pin) and make the measurement check. 4 If the measurement is outside that specified, try fitting a new valve If this does not bring the float height within limits, fit a new float. 7.3b Remove the needle jet holder ... 9 Pilot screw - adjustment 1 This operation is required whenever the pilot screw setting has been disturbed, and before a new limiter cap is fitted. You will require a test tachometer capable of accurately indicating an engine speed change of 100 rpm or less. If you do not have the required equipment, have a dealer service department or a repair shop carry out this check. 2 Set the screw to its initial position (2'',4 turns out). Start the engine, and ride the machine for at least ten minutes to reach normal operating temperature. 3 Connect the test tachometer according to the manufacturer's instructions. Set the idle speed to 1300 ±100 rpm using the throttle stop screw. 4 Slowly turn the pilot screw in or out until the highest engine speed IS obtained. At this point readjust the idle speed to 1300 ± 100 rpm. Turn the pilot screw slowly clockwise until the engine speed falls by 100 rpm. Now back the screw off by one full turn. The pilot screw is now set to the correct position for minimum exhaust emissions. 5 If a new pilot screw has been fitted, fit a new limiter cap, using Loctite 601 or equivalent to retain it. The tab on the limiter cap must be positioned so that further counterclockwise movement is prevented. 7.3c ... and tip out the small needle jet 10 High altitude adjustment - general information cases where the motorcycle is operated continuously at altitudes feet (2000 m) or more, the carburetor must be adjusted to compensate. If the setting is not altered, the mixture may be too rich, causing poor fuel economy and high exhaust emission levels. 2 turn 2 The adjustment requires the pilot screw to be turned by clockwise, and the fitting of a Vehicle Emission Control Information Update Label on the frame downtube. Reset the idle speed to 1 300 ± 1 00 rpm after pilot screw adjustment. 3 If the machine is subsequently used exclusively at low altitudes, the pilot screw setting must be restored to the normal position, or rough idling and stalling may occur. These adjustments should be carried out by an authorized dealer service department who will have access to the 1 of In 6500 ^ update 11 labels. Air cleaner assembly - removal and installation Removal Although removal of the air cleaner case is unlikely to be necessary the normal course of an overhaul, it provides access to the crankcase breather separator and increases access to the purge control valve and 1 in 7 4 Slow jet IS located next to the mam/needle jet bore Chapter 3 Fuel system hoses (California models only). Cleaning of the air cleaner filter should be carried out at the recommended interval, and is described in Chapter 1 Start by supporting the machine upright on a stand or wood blocks, 2 then remove the rear wheel (Chapter 6) and the rear fender (Chapter 5). 89 reconnect the Finally, clip which retains it to the carburetor intake. hose from the crankcase breather stub to the separator unit-. Remove the air cleaner case mounting bolts. There are two bolts 6 below the rider's seat area, and a further three on the right side machine. Two of these are positioned inboard of the battery holder, and the third is normally covered by the fuse box. Disconnect the turn signal relay and wiring connectors at the rear 7 of the ' of the air cleaner case. 8 Slacken the clip ) 1^1^ 1 — 1 1 which secures the air cleaner case to the and out from the frame recess carburetor, then pull the case back through the gap normally covered by the rear fender. 1 Installation 9 The case is installed by reversing the removal operation. In view of the disassembly work involved m removing the case, it is suggested that the breather separator (all models) and the purge control valve (California models) are checked before installation commences. These procedures are described later in this Chapter. 10 When installing the air cleaner case, place it in position and Fig. 3.3 Air 7 Cover 2 Screw 3 4 Cover seal Emission information label 5 6 Separator to 7 Clip - 8 9 Spring retainer Element support 10 Air - 4 off Vacuum hose 2 routing label' air filter hose off California models only filter element 11 Air cleaner case 12 13 14 15 16 17 Air intake hose Bolt - 5 off Clamp hose Hose clamp Air outlet Separator cover the breather separator hose, the turn signal relay, the fusebox, the battery, the seats, the fender, the rear wheel and the side covers. Remove the passenger's and rider s seats. On the right side of the machine, hinge down located fit bolts loosely the battery cover and remove the battery (Chapter 1, section 17). 4 Remove the single bolt which retains the fuse box. 5 On the left side of the machine, remove the left side cover and the air cleaner case cover. Remove the air filter element and disconnect the 3 Now and check that the case is located correctly. tighten the mounting bolts, then refit the air filter element and mounting f T &b Fig. 3.2 1 Checking the float height (Sec cleaner (Sec 11 and 12) 18 Seal 19 Element support plate 20 Separator element 21 Separator body 22 23 24 25 26 Clip 27 Crankcase hose 28 Clip - 2 off 29 Drain hose 30 Clip - 2 off Screw Nut 31 Plug Grommet 32 Screw Drain hose - 4 off 8) Chapter 3 Fuel system 90 12 Crankcase breather separator removal, cleaning and 13 Purge control valve inspection (California models) installation 1 Removal The crankcase breather separator is located just in front of the air attached by a short stub. Its function is to intercept the oil vapor expelled from the crankcase, where a small filter element traps the heavier elements in the vapor, routing them down to a closed drain hose. The remaining vapor is passed through a second hose to a stub on the air filter element, which is bypassed. The vapor is then drawn into the engine and burnt. 2 The crankcase breather separator requires occasional cleaning, the precise frequency of which is dependent on operation conditions In cool damp areas, water vapor will tend to combine with the oil mist from the crankcase to form an emulsion. This will obstruct the separator relatively quickly 3 Constant full-throttle operation will produce a higher volume of oil vapor passing into the separator If the system is not drained frequently, this too can cause obstruction of the separator 4 The separator can be detached for cleaning after the air cleaner case has been removed (Section 11). 5 Remove the separator hoses, then release the four screws which hold the separator halves together 1 The purge control valve requires attention cleaner case, to which it is in the event of poor when the engine is hot Before investigating the valve itself, check that none of the emission control hoses have become blocked or kinked and that all connections are secure. starting 2 If the check on the hoses does not rectify the fault, the operation of the valve must be checked. This requires the use of a vacuum pump and a pressure pump. In view of the cost of this equipment and its infrequent use, it is recommended that the machine be taken to a dealer service department or a suitably equipped repair shop to have the check carried out. is removed, or if any of the emission control hoses are check that they are reconnected and routed properly, following the routing label attached to the machine. 3 If the valve removed, Cleaning Wash out the separator and its element using a non-flammable or high flash-point solvent Squeeze out the element and then allow it and the separator halves to dry. Remove and wash out the separator dram hose. 6 Installation 7 Reassemble the separator by reversing the removal sequence the separator on the check that all Fig. 3.4 air cleaner case Install the air Refit cleaner case and hose connections are secure. Evaporative emission control system operation (Sec 13) 13.1 A: Purge valve B: Charcoal canister (California only) Fuel tank 1985 Purge control valve cleaner ^ Fresh — Fuel air vapour Chapter 4 Ignition system Contents General information 1 Checking the ignition system - general information Spark plug - inspection and renewal Spark plug - checking operation Wiring and switch problems - troubleshooting 2 3 4 5 AC generator charge (source) and pickup coils - testing 6 Ignition coils - testing 7 unit - testing 8 9 CDI Ignition timing - checking Specifications Ignition charge coil 274 - 336 ohms Resistance Ignition pickup coil 90 - Resistance 1 10 ohms Ignition coil resistances 0.17 - 0.19 3.7 - 4.5 K 3.75 - 6.25 Primary coil Secondary coil Spark plug cap ohms ohms ohms Ignition timing Initial 5° setting BTDC at 1300 rpm Spark plug Standard type Extended high speed use Electrode 1 NGK CR6HS NGK CR7HS . gap The ignition system is of the fully electronic CDI (capacitor discharge Ignition) type When the engine is running, electrical power is fed from the ignition charge (source) coil to the CDI unit, where a charge is stored in a capacitor. In this sense the capacitor can be regarded as acting rather like a small battery. When the CDI unit receives a trigger pulse, the capacitor discharges through the ignition coil or ND U20FSR-U ND U22FSR-U (0.024 - 0.028 in) electrodes to earth, the resulting spark igniting the fuel/air mixture the cylinder. General information The mm 0.6 - 0.7 or primary windings. This in its stored current turn induces a high tension pulse in the ignition coil secondary windings, and this is applied to the spark plug. The high tension pulse jumps across the plug trigger incorporated in pulse is provided by the flywheel generator; a past a small pickup coil, sufficient trigger the a small magnet in in magnetic pickup the rotor sweeps generating a tiny signal voltage. This is unit, discharging the capacitor. The absence of mechanical parts in the system means that no maintenance IS required, and In fact no adjustment is possible. This type of ignition system is well established and can be expected to be reliable over a long period of service. Where faults do occur, they tend towards failure of a single component in the system, and can be resolved by the simple expedient of renewing the affected component. to CDI Chapter 4 Ignition system 92 IGNITION COIL PICKUP COIL G/W SPARK PLUGS SWITCH Fig. 4.1 Ignition Bl Black Bu Blue 2 G W system circuit (Sec equipment It IS particularly important that fault in the ignition home many more detailed tests requiring specialised test equipment unavailable to the owner by virtue of its cost Whilst this means that in some cases it will be necessary to resort to an authorized dealer service department or a repair shop for testing work or for confirmation of a suspected fault, it is quite reasonable for the owner to establish the general nature of the problem and to effect a cure in most instances. 3 A certain amount of specialist equipment will be needed to carry is distinctly limited, Y of this Chapter for details. fault is similar, whether the Caution: When dealing with the ignition system, treat it with caution, when switched on. A shock from the GDI system can be unpleasant or even dangerous to the owner, and also risks damage to the GDI unit itself. Check 1 ) Spark Plug of the checks 4 A stroboscopic timing lamp is well worth purchasing in view of its relatively low cost and general usefulness. A small multimeter (or pocket tester should also be considered, since it will prove generally useful for all sorts of electrical tests. A suitable meter can be ordered though Honda dealers or similar types can be purchased from auto accessory shops or electronic hobby shops. 5 Note that when making specific resistance checks, Honda advise that the only meters which can be expected to give the quoted figures using other makes or models of meters, resistance readings may well vary from those specified Either obtain one of the specified meters, or if using another type, have your results confirmed by an authorized dealer service department. can be divided into two main categories; partial or and complete failure. In the case of the former, the problem will often have developed gradually, starting perhaps with unreliable starting, poor running or misfiring. Complete failure is less usual, and often indicates the failure of an individual component. Having decided which type of fault has occurred, follow the 7 sequence of checks as listed below, referring to the relevant Sections it rest of the system. It is preferable to fit a new plug as a precautionary measure. Spark plugs can sometimes prove faulty while appearing quite normal. Fit a new plug into the plug cap and arrange it so that the body of the plug is in firm contact with a good ground point, such as an unpainted part of the engine/transmission unit. Switch on the ignition and operate the starter while watching the plug electrodes. In a normal system, a fat, regular bluish spark should be seen. A weak, irregular or yellow spark, or no spark at all, indicates a fault 3) ignition and engine stop switches are working correctly (refer to Chapter 7). Using the wiring diagram at the back of the book, check through the ignition wiring, looking for damaged or broken leads. Check all connectors for looseness or corrosion. Remember that ground connections are as important as the wiring connections. Check the coil connections as described Ignition coil, HT lead and plug cap above. Test the coil resistances as described in Section 7. Check the pickup coil resistance as described Pickup coil in Section 6. Renew coil if defective. Check the charge coil as described in Section Charge (source) 6 Renew if defective. coil Check the CDI unit resistances, see Section 8. CDI unit If fault persists, have system checked by an authorized Honda dealer service department. Ignition timing The ignition timing should be checked in cases where an intermittent fault or poor running cannot be traced to another cause Inaccurate timing means renewal of the CDI unit. somewhere 4) If Defining the type of fault is the simply out, unlike the first; failure Spark are as follows: Sanwa Electric Tester 07308-0020000 Kowa Electric Tester TH-5H Digital multimeter KS-AHM-32-003 Details Always check the spark plug single most likely cause of because it will eventually wear 2) ) Ignition faults Note that the checks are partial or total. out the tests described in this Chapter. For example, a stroboscopic timing lamp is needed to check the ignition timing, and one of the specified test meters will be required to make accurate resistance 6 Yellow especially any attempt to check a suspected system is approached in a logical and methodical fashion. A haphazard attempt at resolving the fault is likely to prove time consuming, confusing and often inconclusive. It should be noted that the range of tests which can be performed at 2 1 1) Green White Checking the ignition system - general information Test ENGINE AC GENERATOR STOP SWITCH IGNITION 5) 6) 7) intermittent failure 8) Switches, wiring and connectors Check that in the system. the Chapter 4 Ignition system 3 1 In normal circumstances a spark plug of the standard grade should be used, but if the machine Is constantly ridden hard in hot conditions, a change of grade may be required. If problems are experienced it is advisable to consult an authorized dealer service department for advise on any proposed change. 2 When fitting a new plug, always set the electrode gap to the (0.024 - 0.028 in) as described below. prescribed 0.6 - 0.7 clean and readjust a used plug, which can quite permissible to It is 3 then be reused. Many owners, however, may prefer to renew the plug in preference to cleaning. Plugs are not expensive, and this choice of action precludes any risk of being let down by a tired' plug at a later date. If cleaning and refitting is preferred, this is described below. 4 Before cleaning or discarding the plug, refer to the color section which accompanies Chapter 1. This gives useful information on diagnosing general engine condition and mixture strength based on the appearance of the plug electrodes, and can be a helpful troubleshooting aid. 5 The plug electrodes can be cleaned by carefully scraping away the accumulated carbon deposits. This is best done using a combination of a small knife blade and assorted small files and abrasive paper. Take great care to avoid straining the center electrode or the ceramic insulator nose may be chipped or broken. Alternatively, the plug can be cleaned by abrasive blasting, either in a full size garage machine or with one of the small DIY models now available. 6 Once clean, file the opposing faces of the electrodes flat using a mm file. A magneto file or even a nail file can be used for this purpose. Whichever method is chosen, make sure that every trace of abrasive and loose carbon is removed before the plug is refitted. If this is not done, the debris will enter the engine and can cause damage or rapid wear. Whether a cleaned or new plug is to be fitted, always check the gap before it is installed. Use a spark plug adjusting tool or feeler gauges to measure the gap, and if adjustment is required, bend the outer, earth electrode only. Never bend the centre electrode or the porcelain insulator nose will be damaged. 7 electrode 8 Before the plug is fitted, apply a fine coat of PBC or molybdenum disulfide grease to the threads. This will help prevent thread wear and damage. Fit the plug finger-tight, then tighten it by a further V'* turn ensure a gas-tight seal. Beware of overtightening, and always use a plug wrench or socket of the correct size. only, to 4 Using the wiring diagram at the back of this manual, trace through the ignition wiring and check each connector for security, corrosion and the presence of water, paying particular attention to the GDI unit connector. You will need to remove the fuel tank to gain access to the CDI unit. 2 Look for chafed or broken wires and renew or repair these as necessary. Check the ignition switch and engine stop switch for water contamination (see Chapter 6). 3 A quick cure for water in switch or wiring connectors is to spray them with a silicone-based maintenance aerosol. A better long-term measure is to dismantle all connectors, pack them with silicone grease, and then reassemble them. Done properly, the machine will run virtually submerged in water, and there should be no further trouble of fault. Spark plug - inspection and renewal small fine 93 Spark plug - checking operation This IS an essential first step in tracing any suspected ignition fault. 1 With the ignition switched off, remove both spark plugs from the cylinder head and refit them in the plug caps. Place the metal body of each plug in firm contact with a good 2 ground point, such as the unpainted metal of the engine, and in a position where the plug electrodes can be viewed while the engine is cranked over with the starter motor. Switch on the ignition and operate the starter while watching the 3 plug electrodes. If all is well, a regular, fat blueish spark should be seen jumping across the electrode gap. A thin, yellowish or irregular spark is this type. 6 AC generator charge (source) and pickup coils - testing 1 The ignition charge (source) coil is mounted on the flywheel generator stator plate and provides power for the system. Mounted externally to the rotor is the pickup, or pulser coil, which provides the trigger signal which controls the ignition spark 2 If it is suspected that a fault lies in the above coils this can be checked by using a multimeter to test the coil resistances. Start by removing the left side panel to gain access to the various wiring connectors. 3 Trace the AC generator wiring back to the connectors, and separate them. Using a multimeter set on the appropriate resistance range, measure the resistance between the black/red wire and ground. 4 If significantly outside the specified figure, the charge (source) coil should be considered defective. If the test shows a reading of zero ohms, the coil insulation will have broken down, allowing the coil to short to ground. If on the other hand, a reading of infinite resistance is shown, this indicates that the coil windings have broken. Either fault will require the renewal of the stator assembly, but 5 before ordering a new item it is worth having your findings confirmed by an expert. 6 The only renewal are to consult an autobe able to rewind the faulty coil, or to consider buying a used stator from a motorcycle breaker. Removal and refitting of the generator is described in Section 14 of Chapter 2. 7 The pickup coil is separate from the stator assembly and can be renewed individually. To check its resistance, trace back the green/ white and blue/yellow wires to their connector and separate it. Measure the resistance between the two wires. Again, if the reading obtained is significantly different to that specified, the pickup coil must be renewed. The pickup coil is secured by two screws to the inside of the crankcase left side cover. real alternatives to electrical specialist, who may indicative of a fault. 4 If new plug, having set the improve the spark, check the the spark looks weak, try fitting a electrode gap correctly. If this fails to ignition coil resistances as described in Section 7. 5 Where no spark at all is evident, check for a break system wiring or for a fault switch on and off a few times in the ignition the ignition switch. Try turning the it is suspected that the switch contacts in if are dirty or corroded. 6 If the fault persists it will be necessary to check through the ignition system components as described in the following Sections until the cause of the problem is isolated. 5 Wiring and switch problems - troubleshooting id 6 7 Ignition pickup (pulser) A broken or badly connected wire, or dirty or contaminated switch contacts can often be traced as the cause of an ignition or electrical 1 side cover. It is retained by independently of the AC coil is mounted inside crankcase two screws and can be renewed generator stator left Chapter 4 Ignition system 94 8 CDI unit 1 1 In tank. possible at home, given access to a suitable multimeter (see the remarks at the beginning of this Chapter concerning the choice of 7 Ignition coils - testing The ignition coils are mounted on the frame tube, below the fuel To gam access to the coils it will first be necessary to remove the fuel tank (see Chapter 3^. Disconnect the plug lead and low tension wires and remove the coil. If it is suspected that a fault lies in the ignition coil this can be checked by using a multimeter to test the coil resistances. Using a of the primary 7.1 the event of a suspected fault testing in the CDI unit, a certain amount of is meter.) To gain access to the CDI unit, remove the fuel tank (see Chapter The unit is mounted next to the finned alloy regulator/rectifier unit Trace the wiring back to the connector below the unit and unplug it, taking care to pull on the connector body only, not on the wiring 2 3). multimeter set on the resistance range, check the resistance windings by connecting one probe to each of the small low tension terminals. If the reading obtained differs significantly from the specified figure, the coil is defective and must be renewed. 3 Next, measure the secondary resistance by connecting one probe to the ground terminal (green wire) and the other to the plug lead (plug cap removed). 4 If the test gave incorrect resistance readings, the coil is suspect. Note that the resistance tests are not exhaustive: for a more accurate diagnosis, have the coil tested at a repair shop or an authorized dealer service department, on a coil testing machine 2 testing 3 for Before performing the resistance tests, check the wiring connector water contamination or corrosion, these being the most likely faults. Check the various resistances as shown in the accompanying table. The CDI unit terminals are identified in the line drawing which 4 accom;^anies the table. 5 It must be stressed that the above test gives only a rough indication of the condition of the unit, unless one of the specified meters is used. Despite this, most meters will give some indication of significant faults such as open or shorted internal connections. 6 If you are unsure whether your test results are accurate, have the readings confirmed by a repair shop or an authorized dealer service department, or check the unit by substitution. Ignition coils are attached to electrical plate under the fuel tank 8 2 CDI unit PC E is located below fuel tank X RANGE FOR SANWA TESTER USE THE X100 RANGE FOR KOWA TESTER SW EXT SW Fig. 4.2 rubber holder USE THE SW IGN2 in EXT CO PC 00 00 50-300 50-300 CO 2-100 00 0.5-50 PC 50-30 CO E 0.5-50 CO 0.5-50 00 CO CO CDI unit test table (Sec 8) IGN1,2 00 EXT IGN1,2 E CO 00 Chapter 4 Ignition system 9 Ignition timing - checking 1 The ignition timing check need only be performed if there is some reason to suspect its accuracy. It should be noted that no adjustment is possible, and that the only reason for a timing error is a fault in the CDI uni.t. 2 The test requires the use of a stroboscopic timing lamp (strobe), preferably of the xenon tube type, rather than the cheaper and less accurate neon variety. You will also require a test tachometer. In the absence of this equipment, have the test carried dealer service department or a repair shop. out by an authorized 95 Remove the inspection cap near the top of the crankcase left side 3 cover to reveal the rotor edge. Identify the timing F' mark on the rotor, and the fixed index mark on the cover, at the top of the inspection hole. 4 Connect the strobe and the test tachometer, following the manufacturer s instructions, start the engine and direct the beam of the strobe at the fixed index mark. 5 The timing is correct if the 'F' mark aligns with the index mark with the engine running at 1300 rpm. Now increase the engine speed to 3500 rpm and check that the advance lines lie on each side of the fixed index mark. 6 If the timing seems incorrect, check the CDI unit and the charge and pickup coils as described above. Chapter 5 Frame and suspension Contents General information Frame - inspection and repair Handlebar assembly - removal, inspection and installation Front forks - removal and installation Front forks - disassembly, inspection and reassembly Steering head bearings - disassembly, inspection and installation Rear suspension units - removal and installation 1 Rear suspension units - overhaul 2 3 4 Swingarm bushings - checking Swingarm - removal and installation Swingarm bushings - removal and installation 10 5 Rear fender - removal and installation Side stand - maintenance 12 13 6 8 7 Specifications General Frame type Welded tubular Front suspension type Oil-damped telescopic forks 1 40 mm (5.5 in) Front suspension travel Rear suspension type Rear suspension travel Gross vehicle weight rating Vehicle capacity load steel, semi-cradle Swingarm 70 mm (2.8 in) 304 kg (670 lb) 156 kg (344 lb) Front forks 58° Castor angle mm 120 Trail Damping oil 235.5 - 240.5 cc (7.96 - capacity (per leg) Fork spring free length Service limit Oil Fork tube runout (4 7 in) ATF grade 546 mm (21 .5 in) 535 mm (211 m) 0 2 mm (0.008 in) (maximum) 8.1 3 US fl oz) Steering head Bearing ball size 3/16 in Number (per bearing) 21 0.9 - 1.25 kg (1.98 Bearing preload Rear suspension mm mm 187 183 Rear suspension unit spring free length Service limit (7.36 in) (7.20 in) 2.76 lb) Torque specifications Component kg-m Handlebar holder bolts Handlebar holder to upper triple Front axle holder nuts Front axle nut Upper Lower clamp pinch clamp pinch Steering stem nut clamp bolts . ft-lb 14 - 22 2.0 - 3.0 2.7 - 3.3 1.8 - 2.5 5.5 - 7.0 20 - 24 13 - 18 40 - 51 triple bolt 0.9 - 1.3 6.5 triple bolt 3 0 4.0 22 9 0 43 6.0 - 9.4 29 - 65 9 11 Chapter 5 Frame and suspension Component 97 kg-m ft-lb 3.0 - 4.0 0.25 - 0.35 1 .5 - 3.0 22 - 29 Steering head bearing adjuster nut: Initial Final Fork tube cap bolt Fork damper Allen bolt Front turn signal mounting nut Headlight mounting nut Rear Rear Rear Rear Rear Rear brake torque arm nut axle nut brake arm bolt brake pedal pinch bolt suspension unit locknut 0.8 - 'Apply 1 6-9 .2 O "7 O 12. 1 3 - 1 o 22 - 33* 3.8 - 4.8 17-22 27-35 8.0-10.0 58 - 72 2.4-3.0 a locking 1 13-18 CO DO bolts: pivot bolt - 22 - 29 25 - 29 3.0 - 4.5" suspension unit mounting 1 1 .8 2.9 - 3.6 1.8- 2.5 Upper Lower Swingarm 1 - 2.5 - 22 1 1.5- 2.5' 0.4 - 0.5 3.0 - 4.0 3.5 - 4.0 1 .8 - 2.5 8.0 - 1 0.0 Footpeg bolts 1 1 agent 2 General information Free the wiring and control cables from the handlebar by releasing which retain them. Remove the bolts which retain the clutch and front brake lever 3 assemblies to the handlebar. These can be left connected and tied clear of the steering area. Do not allow the front brake master cylinder to hang from its hose. 4 Slacken off the throttle and choke cable adjusters. Remove the screws which retain the left and right handlebar switch assemblies the clips The welded tubular steel frame is of semi-cradle design. At the front frame is the steering head assembly comprising the upper and lower triple clamps, the steering stem and the steering head bearings. The front forks are of the conventional oil-damped telescopic type. Rear suspension is by swingarm supported by dual oil-damped suspension units. The units are adjustable for spring preload. of the Disconnect the choke and throttle cables. Remove the handlebar end plugs after releasing the single screw which retains each one. 6 Remove the handlebar clamp bolts. Lift away the holders and 5 2 Frame - inspection and repair remove the handlebar. 1 The frame is unlikely to require attention unless accident damage has occurred. In most cases, frame renewal is the only satisfactory course of action. A few frame specialists have the jigs and other equipment needed for frame straightening, but even if a suitable repairer can be located, remember that stress damage may not always be visible. 2 Unless the damage is very minor it is usually safer to purchase a new frame. Although the work required to transfer the rest of the engine and frame parts to the new frame is considerable, it can be accomplished in the home workshop. 3 After the machine has covered a high mileage, or if regular cleaning and maintenance has been neglected, rusting will tend to develop around the welded frame joints. The frame joints are high stress areas of the frame, and are also prone to cracking and splitting due to fatigue damage Clean and degrease the frame thoroughly, then check the joint areas carefully for signs of damage damage discovered it may be possible to repair this by welding. If you are experienced in welding and have the necessary equipment, then this can be undertaken at home. Remember that your safety, as well as that of other road users, is dependent on the safety of the machine; it may be preferable to have the welding work carried out by a frame repair specialist 5 After welding has been carried out, or if rusting is found around the frame joints, rub the area down and repaint it. The painting can be done by brush. This avoids the need for extensive disassembly or masking, and the problem of brush marks in the paint is less noticeable on the frame tubes than on large flat areas 4 3 If is Handlebar assembly - removal, inspection and installation Removal Place the machine on a level surface and arrange wood blocks, a machine to raise the front wheel clear of the ground. Make sure that the machine is supported securely before proceeding Remove the fuel tank to avoid paint damage (Chapter 3), or place some thick cloth over it for protection. 1 jack or a stand, beneath the Remove the speedometer, ignition switch, wiring connection box and the front turn signals (see Chapter 7). 8 Remove the single nut which secures each handlebar holder lower section to the upper triple clamp Lift away the holder lower sections and rubber bushes. 7 Inspection 9 If the handlebar has been bent or twisted as the result of an accident, fit a new one. 10 Check the rubber bushes which isolate the holders from the upper triple clamps. Renew them if they have split or deteriorated. Installation 1 1 The handlebar assembly is installed by reversing the removal sequence, noting the following points 12 Align the punch mark on the handlebar with the top of the handlebar holder lower section. Fit the holder upper halves, tightening the bolts to the specified torque figure. Tighten the front bolts first and then the rear bolts. 13 When refitting the throttle twistgrip and cables, grease the twistgrip cable groove and the cable ends. 14 When fitting the right side handlebar switch, locate the pin on the lower switch half in the hole in the handlebar. Fit the front screw first, it before the rear screw is fitted. 15 Fit the front brake lever and master cylinder, noting that the UP' mark on the bracket must face upwards. Align the punch mark on the handlebar with the edge of the bracket. Tighten the upper bolt first, tightening then the lower. 16 Install the choke cable and left side handlebar switch, locating the pin on the lower switch half in the hole in the handlebar. Fit the front screw first, tightening it before the rear screw is fitted. 17 Fit the clutch lever assembly, noting that the 'UP' mark on the bracket must face upwards. Align the punch mark on the handlebar with the edge of the bracket. Tighten the upper bolt first, then the lower 18 Refit the cable/wiring clips to the handlebar. Check that the turn signals and switches work normally. Check and adjust the throttle and choke cables. Check the operation of the front brake before riding the machine. Chapter 98 3 3 Remove 5 Frame and suspension the clutch lever (2 bolts) and separate the switch 4 1 Place the machine on a level surface, leaving plenty of working space around the front end. Support the machine on wood blocks, a stand or a jack, placed under the crankcase to raise the front wheel clear of the ground Make sure that the machine is stable and in no danger of toppling over before starting on the fork removal operation. Remove the front wheel (Chapter 6). 2 Disengage the front brake hose from the guide clip on the front 3 fender Remove the four bolts which retain the fender and lift it away. Slip the speedometer cable through its guide clip as the fender is withdrawn Remove the front brake caliper mounting bolts and lift the caliper hose from being strained Slacken the upper and lower pinch bolts and then pull and twist the 5 fork tube downwards until it comes clear of the triple clamps. 6 Note that if you intend to remove the fork top bolts it is advisable to slacken them before the forks are removed completely Pull the fork tubes down until they are clear of the upper triple clamp Temporarily tighten the lower pinch bolt, then slacken the fork top bolts by ^2 - 1 clear of the fork. Tie the caliper to the frame to prevent the brake turn. Installation 7 Install the fork legs by reversing the removal operation Note that the upper edge of the fork tubes must align with the top surface of the upper 5 triple clamp. Front forks - disassembly, inspection and reassembly Disassembly 1 Remove the fork legs as described in Section 4 Work on one assembly at a time to avoid interchanging parts. 2 Hold the fork tube between soft jaws in a vise, or wrap some soft cloth around it before tightening the vise. Take great care not to scratch the tube surface or to overtighten the vise. Position the fork leg so that the top of the fork tube is inclined upwards. 3 Unscrew the Apply pressure to the bolt Take care to avoid injury or damage as fork top bolt using a socket. comes free from the fork tube. Once spring pressure is released, lift away the top bolt and the fork spring Remove the assembly from the vise and invert over a drain tray to allow the damping oil to dram. Pumping the fork leg will assist the bolt 4 it in expelling the 6 the Work oil oil. rubber mounted and retained by a single nut clamp the dust seal out of recess at the top of the slider Pry out its seal retaining clip with a small screwdriver, taking care not to scratch the fork tube. Separate the slider and fork tube by pulling them sharply apart. The impact between the top and bottom bushes will drive the oil seal, backing ring and top bush out of the slider. 8 Remove the damper seat from the end of the damper rod (If it has remained inside the slider, invert it to tip out the damper seat 9 Remove the circlip from the end of the damper rod. Tip the damper rod and rebound spring out of the fork tube. 10 Slide the dust seal, oil seal retaining clip, oil seal, backing ring and top bush off the fork tube. Do not remove the bottom bush at this 7 ) stage. Inspection 11 Measure the down free length of the fork spring. to the service limit, renew If it has compressed it. 12 Examine the fork tube, slider and the damper rod for signs of abnormal wear or damage. Renew parts as required. 13 Check the damper rod piston ring for wear or scoring. Renew it if damaged. 14 Place the fork tube on V-blocks and check for runout using a dial gauge. If runout exceeds the service limit, renew the fork tube. 15 Inspect the fork bushes for signs of scoring or wear If scoring is noted, or if the Teflon coating has worn through to the copper-colored backing metal on more than three-quarters of its surface, renew the bush(es). (fork tube) bush, spread the bush apart and tube end. When fitting the new bush, do not spread Never attempt to reuse a it any more than necessary to allow fitting bush which has been removed from the fork tube. 16 To remove the bottom slide to counter fork spring pressure. is triple Clamp the lower leg between soft jaws in a vise Using a 6mm hex 5 wrench, remove the damper Allen bolt from the underside of the slider. If the damper assembly turns inside the leg, temporarily install the spring and top bolt to hold it. Front forks - removal and installation Removal 4 3.8 Each handlebar below the upper halves It off the fork Installation 17 Wash all parts in a high flash-point solvent and dry with compressed air or a lint-free cloth. Fit the rebound spring over the damper rod and install the assembly 1 8 in the fork tube. Fit the circlip to the damper rod, and place the damper seat over the end. 19 Insert the fork damper rod damper rod top bolt. bolt tube into the and tighten it slider. Apply a locking agent to the specified torque setting to the If the turns during tightening, temporarily install the spring and Chapter 5 Frame and suspension 99 20 Fit the top bush and backing ring over the fork tube. The fork top bush should be fitted using a driver tool if possible. Failing this, if great care is taken, the bush can be tapped into place using a parallel punch, working around the bush as it is fitted to ensure that it stays square to its bore in the slider. If this method is chosen, be very careful to avoid scoring the fork tube. 21 Fit a new fork seal using the fork seal driver with the appropriate attachment available from an authorized dealer service department. Again, if great care is taken, this operation can be improvised, but be careful to avoid scoring or distorting the seal. 22 Check that the retaining clip the seal, then fit groove is visible above the top edge of the retaining clip. Press the dust seal into place. 23 Measure out 238 cc (8.0 US fl oz) of ATF (automatic transmission and pour this into the top of the fork tube. Work the fork up and down a few times to expel air bubbles. 24 Install the fork spring, noting that the tightly-wound spring coils should face towards the bottom of the fork. Clamp the fork upright between soft jaws in a vise, then fit and tighten the cap bolt. Renew the cap bolt 0-ring if it is damaged. If desired, the final tightening can be left until the fork tube is clamped securely in the lower triple clamp, fluid) during installation. 4.3 Front fender 4.5 Slacken pinch bolts, then twist and pull fork tube out of the triple 5.5 clamps Use Allen screw is secured by four bolts 4.7 Align upper edge of fork tube with triple clamp, then tighten pinch bolts to remove damper rod bolt 5.6 Pry out the wire clip to allow bush and seal to be knocked out 5.24 Fit spring with tighter coils downwards Chapter 5 Frame and suspension 102 H 20062 Fig. 5.1 7 Top bolt 2 3 4 5 6 Damper rod Rebound spring 7 Forl< 0-ring Spring Piston ring 8 9 Bottom bush 70 Damper 77 Dust seal Front forks (Sec 5) 74 75 76 77 78 79 Circlip seat 72 Retaining 73 Oil seal clip Left slider Reflector Dram bolt Sealing washer 20 Damper Allen bolt 27 Sealing washer 22 23 24 25 Right fork leg Stud - 2 off Axle clamp Nut - 2 off tube 6 Steering head bearings installation disassembly, inspection and Disassembly The steering head bearings should be disassembled and checked wear whenever steering operation becomes suspect, or if play or stiffness can be detected. To gain access to the bearings, carry out the 1 for following: Remove Remove Remove Remove Remove Remove Remove Backing ring Top bush the front wheel and brake caliper (Chapter 6) the handlebar assembly (Section 3) the front forks (Section 4) the headlight (Chapter 7) the speedometer (Chapter 7) the wiring connection box (Chapter 7) the front turn signals (Chapter 7) 2 To release the steering stem nut you will need a 30 x 32 mm wrench This can be ordered from an authorized dealer locl^nut service department, or a commercially available equivalent can be used. Remove the steering stem nut, then tap the upper triple clamp 3 upwards until it can be lifted clear of the steering stem. 4 Place an old blanket or similar below the steering head area. This will catch any of the steering head balls which might drop free as disassembly progresses. Note that if the steel balls land on a hard floor, they will bounce away and will almost inevitably be lost. 5 Support the lower triple clamp, then slacken and remove the bearing adjuster nut. Use either the Honda steering stem socket tool or a pin-type spanner wrench. 6 Run the adjuster nut off the steering stem, then carefully lower the lower triple clamp/steering stem assembly clear of the frame. With luck, the top cone and the upper 21 bearing balls will remain in position. The lower bearing balls will usually come away with the steering stem, but some may remain stuck to the lower bearing cup. These should be collected and stored safely. 7 Wash the bearing balls, the steering stem and all removed parts in solvent and allow to dry. Wipe out the bearing upper and lower cups, these being pressed into the steering head. Chapter 5 Frame and suspension Inspection 8 Examine the bearing balls for signs of wear, pitting or corrosion If the balls are marked in any way, renew them as a set. Each bearing race contains 21 -^/le in balls. 9 The bearing cones and cups (races) should be checked for wear and damage. The working surfaces of these parts is hardened, and any marking of this surface finish Indicates the need for renewal. 10 To remove the lower cone from the steering stem, work it up the stem by tapping around the base with small cold chisel or punch. The new cone can be tapped into place (after fitting the washer and dust seal) using a length of steel tube placed over the steering stem 11 The bearing cups can be displaced by passing a long drift punch through the steering head, and tapping the cups out of their bores. The new cups can be tapped Into place. Make sure that they enter their bores squarely. Installation 1 cup and the lower cone with grease. Place 21 steel the groove of each, using the grease to hold the balls in 2 Pack the upper balls in 1 3 Slide the steering stem up through the steering head, taking care to avoid dislodging the balls. Place the upper cone over the end of the steering stem, then fit the adjuster nut, screwing it down finger-tight. Temporarily reinstall the fork legs to align the triple clamps. 14 Check that the assembly turns smoothly. If you are using the Honda steering stem socket, tighten the adjuster nut to the initial torque setting, then turn the steering assembly from lock to lock five times to seat the bearings. The adjuster nut should now be backed off and then retightened to the final torque setting. 1 5 If you are using a pin-type spanner wrench, tighten the adjuster nut down hard, and turn the steering assembly from lock to lock five times to seat the bearings The adjuster nut should now be backed off and then tightened until all detectable free play has just been eliminated, but no more 16 Continue reassembly up to the stage where the forks and front wheel are in place, then check the bearing preload as follows. With the wheel clear of the ground, and pointing straight ahead, hook a spring scale to the fork tube, just above the lower triple clamp. Measure the force required to turn the steering If this Is outide the specified range, check and readjust the bearing preload before completing the Installation operation. position. Fig. 5.2 1 2 3 4 5 6 7 8 9 10 1 1 12 13 14 15 16 17 18 19 20 Steering head assembly (Sec 6) Upper triple clamp Bolt - 2 off Steering stem nut Bearing adjuster nut Top cone Upper bearing balls -21 off Top cup Lower cup Lower bearing balls 21 off Lower cone Dust seal Washer Steering stem I lower triple clamp Bolt - 2 off Cap - 2 off Bolt - 2 off Handlebar clamp - 2 off Rubber bush - 4 off Cap - 4 off Nut - 4 off 103 Chapter 5 Frame and suspension 104 7 Rear suspension units removal and installation Place the motorcycle on level ground, supporting it upright on blocks or a stand placed beneath the crankcase. Check that the machine is stable and that the rear wheel is clear of the ground. 2 Set the spring preload adjuster to the softest setting. Remove the suspension unit upper and lower mounting bolts and remove the unit. If both units are removed, note that the rear wheel will be unsupported and will rest on the ground. Install the unit(s) and tighten the bolts to the specified torque 3 figure. Note that final tightening is best done with the machine on its wheels and mounts. a person seated normally to prevent stressing the rubber 1 wood 8 Rear suspension units 1 In overhaul the event of a problem with the suspension units, little can be of overhaul without suitable workshop equipment This done by way includes a compressor tool and the appropriate attachment to fit the Without this tool, the springs cannot be compressed safely units. 2 It is recommended that any overhaul work is left to an authorized dealer service department or a repair shop. Note that the springs can be replaced if damaged, or worn to the service limit, and that the damper insert can be renewed if it is leaking or bent. The damper is not If any part is renewed, this must apply to both units, never rebuildable one. •» 3 An alternative to renewing parts of the original units is to consider purchasing aftermarket replacements. These often offer improved performance over original equipment parts. Remember that nonoriginal parts may invalidate any remaining warranty on the machine A good repair shop or accessory store can provide information and advice on choosing suitable units. 9 Swingarm bushings - checking Place the motorcycle on level ground, supporting it upright on blocks or a stand placed beneath the crankcase. Check that the machine is stable and that the rear wheel is clear of the ground. 2 Grasp the ends of the swingarm and attempt to move it from side to side. If you can detect any free play, the bushings are worn and should 1 wood be renewed. 10 Swingarm - removal and installation 1 7.2 Suspension units are retained by bolts Place the motorcycle on level ground, supporting it upright on blocks or a stand placed beneath the crankcase Check that the wood machine and that the rear wheel is clear of the ground. wheel as detailed in Chapter 6. the suspension unit lower mountings (Section 7). drive chain guard and brake pedal return spring. 3 Slacken and remove the swingarm pivot bolt nut. Support the weight of the swingarm and withdraw the pivot bolt. If- it is tight, use a long piece of bar as a drift and tap it out Lower the swingarm clear of the frame, disengage it from the chain and place it to one side 4 Before installing the swingarm, check that the pivot sleeves and dust seal lips are greased. Refit the swingarm by reversing the removal operation. Grease the bushings using the grease nipples provided. is Remove the 2 Remove Remove the Fig. 5.3 1 2 3 4 5 6 7 stable rear Rear suspension unit (Sec 8) Top mounting bolt Washer Bushing - 2 off Top mounting 8 9 Spring cover Spring Spring lower seat 12 Lower mounting bolt 13 Inner sleeve Locknut Bump stop 10 Preload adjuster 1 1 Damper 10.2 Use screwdriver and wire loop to disengage brake pedal return spring Chapter 5 Frame and suspension 10.3 Remove pivot shaft and lift the swingarm away 10.4 Tighten swingarm pivot to specified torque Fig. 5.4 7 2 3 4 11 1 to Pivot bolt Dust seal ~ 4 off Pivot sleeve ~ 2 off Bushing - 4 off Swingarm bushings - Swingarm (Sec 10 and 11 Nut 9 Grease nipple - 2 off 10 Swingarm 7 Ctiain slider 1 1 8 Screw 12 End plate - 2 off 5 6 3 off removal and installation Rennove the swingarm (Section 1 0). Wash the swingarm in solvent all old grease and road dirt. Remove the chain slider (three remove 105 Collar - 3 off Ctiain adjuster - 2 off 13 Washer - 2 off 14 Adjusting nut - 2 off 15 Locknut - 2 off screws) and the brake torque arm (cotter pin and single nut). Lift off the dust seal caps and push out the collars from the inside of 2 the bushings. To extract the bushings you will need a slide hammer and adaptor set. These can be obtained locally, or as Honda parts from an authorized dealer service department. . Chapter 5 Frame and suspension 106 You may be able to avoid the requirement for special tools with a ingenuity The bushes are headed and there is a small gap at the centre of the bore, between the two You can use this to lodge a parallel punch against the edge of the bushings, which can then be driven out. Alternatively, carefully hacksaw through the bushing wall taking care not to cut into the metal of the swingarm. The bushings can then be partially collapsed and pushed out. 4 The new bushings can be drawn into position using a drawbolt arrangement made up from a length of threaded rod, and some nuts and washers. A similar tool is shown in the accompanying drawing. Note that whichever method of removal is chosen, the bushings must 3 little not be reused. 12 Fenders - removal and installation Front fender 1 The front fender will requiie removal to permit removal of the front fork legs from the triple clamps. Support the machine securely on a stand with its front wheel clear Chapter 6 and remove the front wheel. Slip the speedometer cable through its guide on the fender and disengage the hydraulic hose clamp. Release the four mounting bolts and remove the 2 of the ground. Refer to 1 1 2a the dust seal caps Lift off fender. Rear fender 3 You will need to remove the rear fender only on rare occasions, for example to allow removal of the air cleaner case. Start by placing the motorcycle on level ground, supporting it upright on wood blocks or a stand placed beneath the crankcase. Check that the machine is stable and that the rear wheel is clear of the ground. 4 If required, remove the rear wheel as detailed in Chapter 6. Remove the suspension units (Section 7). Remove the passengers seat {2 bolts) and the rider's seat (2 bolts). 5 Disconnect the wire connectors to the turn signals and taillight. Remove the turn signals. Remove the six bolts which brackets. Remove the brackets and 6 7 Install secure the fender to the fender the fender the fender by reversing the removal sequence. 13 Side stand maintenance These models are equipped with a side stand only, so regular maintenance is essential to avoid any risk of its failure. Check the condition of the pivot and spring, and renew the rubber pad when it has worn down to the service limit line. For details, refer to Chapter 1 1 1 .2b Push out the inner collars for inspection 5 Fig. 5.5 Swingarm bushing installation drawbolt tool (Sec 11) 7 1 1 .3 them Tap out the old swingarm bushes - do not attempt to reuse 2 3 4 Nut Thick washer 5 6 Thick washer Bolt Tube 7 Bushing Swingarm Chapter 6 Wheels, brakes and tires Contents General information Wheels - inspection and repair Wheels - alignment check Front wheel - removal and installation Front wheel bearmgs ~ inspection and renewal 1 Front brake master cylinder - disassembly, inspection and 2 installation 3 Front brake hydraulic system - draining, refilling and 4 10 Front disc brake - inspection 6 Front disc brake - pad renewal 7 Front brake disc - removal and installation Front brake caliper - disassembly, inspection and installation 8 bleedmg Rear wheel - removal and installation Rear wheel - disassembly, inspection and bearing renewal Rear brake - inspection and overhaul Tires - removal and installation 9 Tire tubes - repair 5 Wheels Wire spoked, chrome plated limit) - axial and radial Axle runout (maximum) 2.0 0.2 mm mm (0.08 steel rim in) (0.008 in) Front brake Type Swept Single hydraulic disc 179.8 cm^ (27.9 sq in) 4.0 (0.16 in) 3.5 (0.14 in) 0.3 (0.012 in) Dual piston, floating area mm mm mm Disc thickness Service limit Disc runout (maximum) Caliper type Caliper piston outside diameter Service limit Caliper inside diameter Service limit Master cylinder piston outside diameter Service limit Master cylinder bore inside diameter Service limit mm (0.9987 in) mm (0.9961 in) 25.4 mm (1.00 in) 25.450 mm (1.002 in) 12.7 mm (0.5 in) 12.64 mm (0.498 in) 12.7 mm (0.5 in) 12.755 mm (0.5022 in) 25.368 25.300 Rear brake Type Swept Single leading shoe area Rear brake drum inside diameter Service limit Rear brake lining thickness Service limit Tires Type 123 cm^ (19.1 sq 130 mm (5.12 in) 131 4.0 2.0 mm (5.16 in) mm (0.16 in) mm (0.08 in) Tubed Rear Tire pressures (front and rear) (sis) in) Size: Front 12 13 14 15 1 Specifications Type Rim runout (service 1 3.00-18-4PR 1 30/90-1 5-66P 28 psi (2.00 kg/cm' drum Chapter 6 Wheels, brakes and 108 tires Torque specifications Component kg-m 1.8 - 2.5 13 Front axle nut Front brake disc nnounting bolt 5.5 - 7.0 40 Front brake caliper mounting bolts Front brake caliper pad pin bolt Front brake master cylinder clamp bolts 0.4 - 0.7 2.4 - 3.0 1.5 - 2.0 17-22 11 - 1 .8 - 2.5 8.0 - 10.0 6.0 - 7.0 0.8 - 1.2 1.8 - 2.5 wheel sprocket nuts brake arm bolt brake pedal pinch bolt General information The wheels are of the conventional wire spoked type, with plated Tubed tires are fitted at the front and rear. The front brake is a single hydraulic disc arrangement which employs a floating dual piston caliper. The rear brake is a mechanically operated single leading shoe drum unit. steel rims. 58 - 72 43 - 51 6-9 13 - 18 Wheels 3 - alignment check 1 Misalignment of the wheels, which may be due to a cocked rear wheel or a bent frame or triple clamps, can cause strange and possibly serious handling problems If the frame or triple clamps are at fault, repair by a frame specialist or replacement with To check the alignment you will or a perfectly straight piece of Wheels - inspection and repair Spoked wheels should be checked periodically to ensure that the true. The spoke tension should be checked and if necessary adjusted, to prevent damage to the wheel or inner tube from loose or broken spokes. The wheels should be checked carefully after even 1 wheels run minor accidents, or if an obstacle in the road has been run over. 2 The wheels should be checked after they have been cleaned thoroughly. The routine checking procedure for the wheel and tire condition is described in Chapter 1 Further checks are detailed below. Place the machine on level ground, and raise the front wheel clear 3 of the ground by placing wood blocks, a jack or a stand, below the crankcase area. Make sure that tne motorcycle is stable in this position. 4 Make up a simple pointer from a length of stiff wire and attach it to the fork leg so that the end of the pointer is almost touching the side edge of the wheel rim. The pointer does not need to be sophisticated, and can be held in place with modelling clay or similar 5 Turn the wheel, and check the amount of axial play (side-to-side wobble) Now relocate the pointer so that it runs next to the inside face of the rim and repeat the check to assess radial play (up and down wobble). If the play exceeds the service limit the spoke tension must be adjusted to pull the rim back into shape. The check can be repeated on the rear wheel, this time with the pointer attached to the swingarm. 6 In cases where the runout is significant, or the rim is obviously buckled or dented due to impact damage, a new rim will have to be built onto the hub. This is skilled work and best left to a specialist wheel builder. Depending on the wheel condition, a wheel builder may be able to true an apparently badly damaged wheel, but if this is not possible, he will be able to advise on the best course of action and carry out the work quickly and economically. 7 Alternatives to rebuilding are to buy a complete wheel, either new or used. If a used wheel is considered, check it very carefully for damage before buying. 8 The method of trueing a bent, or out of round wheel, are to slacken spokes on one side of the hub and then tighten the corresponding spokes on the other side of the hub This sounds easy, but is in fact a . new parts are the only alternatives. 2 2 14 7-10 18-25 13-18 1.0-1.4 2.5 - 3.5 Front brake hose union bolt brake torque arm nut axle nut Rear Rear Rear Rear Rear 18 - 51 27 - 31 2.9 - 5.1 3.7 - 4.3 Front brake caliper bleed valve 1 ft-lb Front axle holder nuts need an wood and assistant, a length of string a ruler graduated in V64 in weight will also be required. Have an assistant hold the motorcycle upright, then measure the 3 width of both tires at their widest points. Subtract the smaller measurement from the larger measurement, then divide the difference by two. The result is the amount of offset that should exist between the front and rear tires on both sides. 4 If a string is used, have an assistant hold one end of it about half way between the floor and the rear axle, touching the rear sidewall of increments. the A plumb bob or other suitable tire. 5 Run the other end of the string forward and pull it tight so that it is roughly parallel to the floor. Slowly bring the string into contact with the front sidewall of the rear tire then turn the front wheel until it is parallel with the string. Measure the distance from the front tire sidewall to the string 6 Repeat the procedure on the other side of the motorcycle. The distance from the front tire sidewall to the string should be equal on both sides. 7 As was previously pointed out, a perfectly straight length of wood may be substituted for the string. The procedure is the same. 8 If the distance between the string and tire is greater on one side, or Drive chain if the rear wheel appears to be cocked, refer to Chapter 1 , and check the alignment of the rear wheel in the swingarm. Also, refer to Chapter 5. Swingarm bushings - checking, and make sure the swingarm is tight. adjustment, very skilled operation. 9 Tightening or loosening spokes results in movement of the rim in both the axial and radial planes, and it is easy to get the wheel in worse shape than when you started. Also, the end of any spoke that has been tightened by more than about one turn will tend to protrude into the rim well area, and may puncture the tube if the end is not filed back. For these reasons, all but routine and minor spoke tension checks should be left to an expert. 10 Finally, where the wheel is being checked after impact damage, remember that the tire may have also been damaged. This damage may not be easily visible, and damaged internal plies could mean sudden failure at a later date. A new tire is the safest course of action here. Fig. 6.1 Method A and C of checking the wheel alignment (Sec 3) - Incorrect B - Correct Chapter 6 Wheels, brakes and 9 If the front-to-back alignment is correct, the wheels still may be out of alignment vertically. 10 Using the plumb bob, or other suitable weight, and a length of check the rear wheel to make sure it is vertical. To do this, hold the string against the upper tire sidewall and allow the weight to settle just off the floor. When the string touches both the upper and lower tire sidewalls and is perfectly straight, the wheel is vertical. If it is not, have the assistant tilt the machine accordingly. 1 1 Once the rear wheel is vertical, check the front wheel in the same manner. If both wheels are not perfectly vertical, the frame and/or major suspension components are bent. Front wheel - removal and installation Removal 1 Place the machine on level ground, then raise the front wheel clear ground by placing wooden blocks or a jack below the crankcase. of the Use ropes or webbing straps to hold the machine securely and vertically in this position Fig. 6.2 2 Axle Brake disc 3 Bolt 1 6 off Remove the single screw which secures the speedometer cable to gearbox. Disconnect the cable and lodge it clear of the wheel. Remove the axle clamp nuts, then unscrew the axle. The wheel can 3 now be lowered until the disc clears the caliper, and removed. To prevent the caliper pistons being expelled accidentally, place a wood 2 its string, 4 109 tires 4 5 6 wedge between the pads. 4 Remove the spacer from the right side of the hub and the speedometer gearbox from the left side. Installation 5 Check that the disc surface is free from grease or dirt. Fit the spacer to the right side of the hub. Pack the speedometer gearbox with grease and install it on the left side of the hub, making sure that the drive tangs engage in the slots in the gearbox. 6 Remove the wood wedge from between the caliper pads. Place the wheel m position and turn the speedometer gearbox so that the raised tang rests against the back of the lug on the left fork slider. 7 Fit the axle holder with the arrow mark facing forward. Fit the holder nuts loosely. Install the axle and tighten to the specified torque. Evenly tighten the holder nuts to the specified torque. Reconnect the speedometer drive cable. Operate the front brake several times to settle the pads and pistons. Front wheel (Sec 4 and 5) Spacer 7 Spacer Oil seal 8 Speedometer Bearing - 2 off 9 Oil seal 10 Speedometer drive gear drive ring 1 1 Washer - 2 off 12 Speedometer gearbox J Chapter 6 Wheels, brakes and 110 4.2 Speedometer drive cable 4.3b Remove the axle and is lift retained by a single screw the wheel clear of forks tires 4.3a Slacken or remove the axle holder nuts 4.5 Speedometer gearbox slots must align with driving tabs 5 Front wheel bearings - inspection and renewal 1 The wheel bearings can be checked for wear or damage after the wheel has been removed from the machine as described in Section 4. Turn each bearing inner race with a finger, feeling for any roughness or tight spots. If the bearing does not turn smoothly and evenly, or if there is obvious free play in it, renew both bearings as a set. The bearings locate in bores in the light alloy hub unit and are 2 separated by a tubular spacer. Start by removing the dust seal and spacer from the right side of the hub, using a screwdriver to prise the It will probably be damaged during removal and should be renewed during installation. The dust seal on the left side of the hub should also be prised out 3 seal out. 4.6 Position raised section of speedometer gearbox as shown and the speedometer drive ring lifted out. 4 To remove the bearings, place the wheel on its side on the workbench, supporting the hub on blocks so that the lower bearing Chapter 6 Wheels, brakes and 111 tires can be driven out Pass a long drift punch through the upper bearing and displace the tubular spacer by levering it to one side. 5 Lodge the end of the drift against the edge of the inner race of the lower bearing, then drift it downwards, working around the bearing to keep it square in its bore. When it comes free, remove it and the spacer, turn the wheel over and repeat the process on the remaining bearing. 6' Note that removal will probably cause damage to even a good bearing; so do not reuse bearings once they have been removed from the hub. Lubricate the 7 new bearings by packing them with grease. Tap the Ensure that the drift bears only on the bearing outer race. Note that it is vital that the bearing enters the bore squarely, and thats its sealed face is fitted outermost. Turn the wheel over and fit the spacer, then install the left right side bearing into position, using a socket as a drift. side bearing. 8 new dust seal on the right side of the hub, and remember to the spacer which sits in the seal. Place the speedometer drive ring the left side hub recess, then fit a new dust seal. Fit a refit in 5.5 Bearings can be driven out of wheel 5.7a Fit first bearing, invert wheel and 5,7c Use large socket to drive bearing fit hub spacer home 5.8a Install new seal on right side of hub 1 Chapter 6 Wheels, brakes and 112 Do 5.8b not omit to fit tires 5.8c Place speedometer drive ring against bearing the spacer operation of the machine, the disc may be warped. Attach a dial indicator set up to the fork slider and check the disc runout. If the runout IS greater than specified, replace the disc with a new one. If a dial indicator is not available, an authorized dealer service department or 7 motorcycle repair shop can make a new seal to left side of 6 Front disc brake 1 Carefully hub as shown inspection examine the master cylinder, the hoses, and the caliper Pay particular attention to the hoses. If they are cracked, abraded, or otherwise damaged, renew them. If leaks are evident at the master cylinder or caliper, they should be overhauled by referring to the appropriate Sections in this Chapter. 2 Check the lever for proper operation. It should feel firm and return to its original position when released. If it feels spongy, or if lever travel is excessive, the system may have air trapped in it. Refer to Section 1 unit for evidence of brake fluid leakage. and bleed the brakes. 3 Check the brake pads for excessive wear by referring to Chapter 1, Tune- up and routine maintenance. 4 Examine the brake disc for cracks and evidence of scoring. Measure the thickness of the disc and compare it to the specifications. If it has worn beyond the service limit, it must be renewed. 5 If the brake lever pulsates when the brake for you. friction material contains asbestos, which is inhaled in dust form. When working on the brakes, wear a particle mask. Do not work in an unventilated area and do not use compressed air to clean brake dust off the brake parts Warning: Brake fluid will damage paint and most plastics Any fluid spills must be washed off immediately. Take care to avoid excessive skin contact and on no account allow the fluid to enter the eyes or mouth Seek medical advice if this occurs dangerous Fit check Front disc brake - pad renewal Warning: 5.8d this is applied during Bral<.e if 1 If the brake pads become worn (see Chapter 1 ) or contaminated with brake fluid, oil or dirt, they must be renewed. Failure to do so will result in damage to the disc and seriously impaired stopping power 2 Remove the pad pin bolt plugs from the caliper. Loosen the pad pin bolts. Remove the caliper mounting bolts and lift the caliper assembly clear of the disc and fork slider. Support the caliper after it has been withdrawn from its mountings and do not allow any undue strain to be placed on the hydraulic hose. 3 Remove the pad pins and lift out the pads and pad spring, noting the position of the pad spring so that it can be located correctly on reassembly. Clean the caliper and pad spring with a solvent-moistened shop towel. Beware of inhaling brake dust (see above warning) and dispose of the used shop towel safely. 4 Push the pistons fully back into the caliper. When doing this, make sure that the displaced fluid does not get expelled from the master cylinder reservoir. Place the pad spring back into its original position, then fit the new 5 pads. Secure the pads by fitting the pad pin bolts. 6 Install the caliper over the disc edge and fit the caliper mounting bolts. Tighten the mounting bolts and the pad pin bolts to the specified torque settings. Install the pad pin bolt plugs and tighten them securely. 7 pads and the back to the normal working position. Operate the front brake lever repeatedly to pistons. During the first few settle the strokes, the lever will pull right handlebar as the pistons are pushed to their 7.2a Remove plugs and 7.3a Withdraw pad pm slacken pad pin bolts bolts and remove inner pad 7.3c Remove 7.2b Remove caliper mounting bolts 7.3b Note position of pad spring outer pad and clean the assembly and lift caliper clear of disc . 114 Chapter 6 Wheels, brakes and Fig. 6.3 1 2 3 4 Front brake caliper (Sec 7 and 9) Plug - 2 off Pad pin bolt Bolt - 2 off - 2 Caliper Bhed 7 Bleed valve cap 8 9 Lower pin bolt Wave washer Boot Upper pin bolt Boot Nut - 2 off Piston - 2 off 1 1 72 13 14 off 15 Piston seal - 2 off 16 Dust seal ~ 2 off 17 Pad spring 18 Pad - 2 off Mounting bracket 5 6 10 tires valve J^^H. 20065 8 Front brake disc - removal and installation The attached to the front wheel hub by six after the wheel has been removed as described in Section 4. 2 When installing the disc, fit the mounting bolts loosely, then tighten in a criss-cross pattern in small steps until the specified torque setting is achieved Check that all traces of grease are removed from the disc surface before installing the wheel. 1 front brake disc is Allen-headed bolts and can be detached Remove the caliper bracket and the caliper bracket pin boots. Wrap shop towel around the caliper and position it so that the pistons face downwards. Remove the plug from the brake hose union hole, and then apply short bursts of compressed air to expel the pistons. Be 4 a careful to avoid trapped fingers as the pistons emerge. and piston Clean the diassembled (do not use regular solvents). Each of the internal surfaces must be clinically clean before reassembly commences. Carefully pry out the dust 5 seals. caliper parts in clean brake fluid or isopropyl alcohol Inspection 6 Check the and piston surfaces for scratches, scoring or due to dirty or degraded brake fluid and mean that new parts must be fitted There is no point rebuilding a scored caliper; it will leak and it is dangerous to do so in view of the risk caliper bore corrosion. These are usually 9 Front brake caliper - disassembly, inspection and installation Warning; of brake failure. friction material contains asbestos, which is inhaled in dust form When working on the brakes, wear a particle mask Do not work in an unventilated area and do not use compressed air to clean brake dust off the brake parts. Warning: Brake fluid will damage paint and most plastics. Any fluid spills must be washed off immediately Take care to avoid excessive skin contact and on no account allow the fluid to enter the eyes or mouth Seek medical advice if this occurs. dangerous Brake if Removal and disassembly If 2 Remove same thread renew Check the figure, 8 If the fit is it. fit of the caliper bracket pins in their bores in the caliper. loose or sloppy, renew the caliper bracket pins, bush or the caliper as necessary to restore Reassembly and Check Use new 9 smooth operation. installation that the caliper bores caliper seals and dust and pistons are clean and dust free. seals, coating them with new fresh the union bolt from the caliper. brake fluid before installing in their grooves. 10 Apply new fresh brake fluid to the pistons and fit them into the bores with the open end facing outwards. 1 1 Fit the pad spring into position in the caliper recess. 1 2 Apply silicone grease to the caliper bracket pins and their boots. Fit size to plug the caliper hole, the the caliper is to be removed completely, as in the case of a caliper overhaul, or if the brake hose unions need to be detached, drain the brake fluid as described in section 1 1 1 7 Measure the caliper bore and piston diameters and compare them with the specified dimensions. If either part exceeds the service limit Use a plain bolt of the and tape a plastic bag over the end of the hose to exclude dirt. 3 Slacken the pad pin bolts and remove the caliper mounting bolts. Remove the pads and the pad spring (Section 7). new boots and then fit the caliper bracket. 13 Install the pads and refit the caliper (Section 7). 14 Reconnect the hose union using new sealing washers. 15 Refill and bleed the hydraulic system (Section 11) Chapter 6 Wheels, brakes and 10 Front brake master cylinder and installation Inspection - disassembly, inspection Warning: Brake fluid will damage paint and most plastics Any fluid must be washed off immediately Take care to avoid excessive skin contact and on no account allow the fluid to enter the eyes or if this occurs. Removal and disassembly 1 if the master cylinder a full overhaul, or if is to be removed completely, as in Clean the dismantled parts in clean brake fluid or isopropyl alcohol use regular solvents Each of the internal surfaces must be clinically clean before reassembly commences 6 Check the piston and its primary and secondary cups for scoring or deterioration. Note that the piston and cups are supplied only as an assembly and must be renewed as such. 7 Check the master cylinder bore for scoring or scratches. Fit a new master cylinder if any damage is found. 8 Measure the piston outside diameter and the cylinder inside diameter. Renew either or both parts if worn beyond its service limit. 5 - spills mouth. Seek medical advice 115 tires the case of do not the brake hose unions need to be detached, drain the brake fluid as described in Section 1 1 You will also need to remove the rear view mirror (right side), the front brake switch wires and the front brake lever Cover the fuel tank and instrument area with an old . blanket or similar to avoid contact with brake fluid spills 2 Disconnect the brake hose union at the master cylinder end whilst holding a shop towel beneath the union to catch any drops of fluid. Tape a plastic bag around the union to keep dirt out of the system. 3 Remove the front brake switch from the master cylinder, then release the master cylinder mounting bolts and clamp and remove the master cylinder Wipe off all external dirt and place the unit on a clean bench area for disassembly. 4 Remove the boot from the end of the master cylinder. Press in on the end of the piston with a thumb and remove the circlip which retains the piston assembly. Remove the piston assembly and the spring. Reassembly and installation 9 Coat the piston assembly and the cylinder bore with new fresh brake fluid. Place the spring in the cylinder bore, narrower end outwards. Fit the piston assembly, being careful not to turn the cup lips inside out during fitting. 10 Compress the piston against spring pressure and install the circlip, ensuring that it seats fully. Fit a new dust boot. 1 1 Continue reassembly and installation by reversing the removal sequence. Note that the edge of the master cylinder clamp must align with the punch mark on the handlebar and that the UP' mark should face upwards. Tighten the upper bolt first, then the lower bolt. 12 Reconnect the brake hose using new sealing washers. Fill and bleed the hydraulic system as described in Section 1 1 Refit the brake switch and the rear view mirror. . 12 (0 Fig. 6.4 1 2 3 4 5 Screw - 2 Front brake master cylinder (Sec 10) 6 Clamp Reservoir cover 7 Diaphragm Diaphragm 8 9 Bolt - 2 off Protector off plate Spring 10 Piston 1 1 Circlip 12 Boot 13 Brake lever 14 15 16 17 Pivot bolt Nut Brake switch Screw Master cylinder J 116 Chapter 6 Wheels, brakes and 10 3a Release front brake light switch from lever assembly 10.3b Release master cylinder clamp bolts (arrowed) 5 Front brake hydraulic system - draining, refilling and bleeding 11 Warning: Brake fluid will damage paint and most plastics. Any fluid must be washed off immediately. Take care to avoid excessive skin contact and on no account allow the fluid to enter the eyes or spills mouth. Seek medical advice the disc if this occurs. If brake fluid contaminates and pads, renew the pads and make sure that the disc is cleaned Draining and mstrument area with an old blanket or brake fluid spills. Connect a length of plastic tubing to the head of the caliper bleed valve, placing the open end into a dram tray or similar container. 2 Open the valve by about V2 - 1 turn, then operate the brake lever repeatedly until no more fluid emerges. Close the bleed valve. 3 Collect and dispose of the old fluid safely. Never attempt to reuse it, even if it looks clean. Hydraulic fluid is hygroscopic (it absorbs water vapor from the atmosphere). This degrades the fluid, lowering its boiling point and promoting internal corrosion in the hydraulic system. 1 Cover the fuel tank similar to avoid damage from and bleeding Remove the reservoir cap and diaphragm. new fresh DOT 3 or DOT 4 hydraulic fluid. Filling 4 1 1 .9 Connect tubing Fill or brake bleeder to bleed valve tires the reservoir with Connect a brake bleeder to the bleed valve. Honda recommend the MITYVAC or a similar equivalent which has a hand operated suction pump to draw the fresh fluid through the system 6 Open the bleed valve, then operate the bleeder pump to draw the fluid through. Check the level of the fluid and keep in the reservoir at frequent topped up. Note that if air enters the system from the reservoir the operation must be started again. 7 Once all signs of air bubbles have vanished, tighten the bleed valve. Operate the brake lever. If it feels spongy, there is still air in the system and it should be bled again. If you find that air is drawn in around the bleed valve threads, remove the valve and seal the threads with Teflon intervals, it tape. If you do not have a brake bleeder, follow the following alternative 8 procedure. 9 Connect a length of plastic tubing to the bleed valve and place the open end in a jar containing enough fluid to submerge the open end. 10 Operate the brake lever a few times until air stops flowing from the small inlet hole in the reservoir and some lever pressure can be felt. Hold the lever in, and open the bleed valve briefly by about V2 turn. Now release the lever and wait for several seconds to allow the fluid level to stabilise. Top up the reservoir as required. 11 Repeat the sequence detailed in paragraph 10 until the fluid emerging from the tubing contains no air bubbles. At this stage, check that the lever feels normal with no sign of sponginess. If all is well, fill the reservoir to the upper level mark and install the cap. 1 1 .1 Oa Remove reservoir cover and diaphragm Chapter 6 Wheels, brakes and stable in this 117 tires position and use ropes or webbing straps to secure it if required. R-pin or cotter pin which secures the brake torque arm the nut and free the torque arm from the brake backplate. Unscrew the brake adjusting nut from the brake arm. Disengage the 3 brake rod by depressing the brake pedal. Fit the trunnion and adjusting nut onto the brake rod for safekeeping until the wheel is installed. 4 Remove the axle nut, then back off the chain adjusters and push 2 nut. Pull out the Remove the wheel forward. Lift the chain off the rear wheel sprocket, then pull out the axle and lower the wheel to the ground. 5 Remove the spacer from the right side of the wheel and lift the wheel clear of the frame Installation 6 If removed, Check fit and swingarm. the chain adjusters into the ends of the swingarm is fully inserted into the damper that the final driven flange headed collar is in place. around the rear wheel sprocket. Lift the wheel into position and fit the spacer on the right side, then slide the axle through the adjusters, wheel and spacer from the right side. 8 Fit the axle nut finger-tight only. Fit the torque arm to the brake backplate and secure it with the nut, plain washer and rubber washer. Fit a new cotter pin or R-pin Reconnect the brake rod and fit the rubbers, and that the 7 1 1 .1 Ob Keep reservoir drive chain adjuster nut loosely. topped up during bleeding operation 9 Adjust the drive chain tension and check that the rear wheel aligned correctly Torque tighten the rear axle nut 12 Rear wheel - removal and installation Removal 1 Loop the Raise the rear wheel clear of the ground by placing a stand, jack or blocks under the crankcase. Make sure that the motorcycle is wood 10 It is important to check that the brake adjustment is set correctly. There should be 20 - 30 mm (0.8 - 1 .2 in) free play at the pedal end. Make any adjustment with the brake rod adjuster nut. Check also that the rear brake lamp comes on just before the brake starts to take effect. If adjustment is needed, slacken the switch body nuts, and raise or lower the switch body until the lamp comes on at the required point. Tighten the locknuts. iFWD Rear wheel (Sec 12 and 13) Fig. 6.5 ; 2 3 4 Nut 5 6 Spacer Nut -4 off Sprocltet 9 Final driven flange 10 Damper rubber - 4 off Oil seal Bearing 7 Headed 8 Stud ~ collar 4 off is 0-ring 12 Bearing - 2 off 11 13 Spacer 14 Spacer 15 Axle Chapter 6 Wheels, brakes and 118 tires contamination should be identified and rectified before the new shoes are fitted. The lining material should not be less than 2 0 mm (0 08 in) thick any point. If it has worn to, or beyond, this service limit, renew the shoes as a pair 4 If the lining material is within limits, but has become glazed, it is permissible to roughen the surface with abrasive paper to restore braking efficiency. This job must be done outside, and a dust mask should be worn to avoid inhaling any of the dust, which contains asbestos This applies equally when removing dust from the drum or 3 at the brake backplate. The drum will not wear very quickly, but if it has reached the service If the drum surface has become scored it is it must be renewed. permissible to have it skimmed on a lathe to correct the scoring, provided that this does not take the diameter beyond the service limit. Drum ovality is usually due to badly tensioned wheel spokes Have 6 this checked by an authorized dealer service department, a repair shop or by a wheel specialist. As a last resort, this too can be corrected by skimming if it is not too severe. Fitting a new drum/hub assembly is a job for a professional wheel builder; it is not recommended that this be tackled at home. 7 To remove the shoes, remove the cotter pin and washer from the pivot and turn the brake arm through 90" so that the shoes are pushed fully outwards by the cam Remove the shoes by folding them inwards until they can be disengaged from the pivot and cam, and the return 5 limit 1 2.8 Secure torque arm nut with new cotter pin springs released. 8 Remove the pinch bolt which retains the brake arm to the cam, lifting the arm off the cam splines Lift off the wear indicator and the then push the cam out of its bore in the backplate Clean the brake backplate components thoroughly with solvent, removing all traces of old grease and brake dust Allow the various parts to dry before reassembly commences. Before the new shoes are fitted, apply strips of masking tape or similar to the lining surface This will prevent them from getting grease or oil spots on them during felt seal, 9 13 Rear wheel - disassembly, inspection and bearing renewal Disassembly With the rear wheel removed as described in Section 12, pull the wheel sprocket hub away from the damper rubbers. Lift away the rear brake backplate assembly. Remove the headed spacer from the center of the hub unit Do not separate the sprocket from the hub unit. 1 rear Inspection Check the condition of the 2 damaged, the sprocket will have sprocket When if this is similarly installing the new wheel sprocket teeth. If worn or renewed, together with the drive worn. The sprocket is retained by four nuts. rear to be sprocket, tighten the nuts criss-cross pattern until the specified torque figure in is small steps reached. in a 3 The sprocket hub contains a bearing and an oil seal. Check the bearing by turning it with a finger. If it seems rough, stiff or unusually loose and noisy, renew the bearing. Support the hub on wood blocks and drive out the old bearing using a large socket as a drift. 4 Pack the new bearing with grease and then tap it squarely into the hub. Use a socket to fit the new bearing, driving it in by the outer race only. Fit a new oil seal and then fit the headed spacer. Examine the damper rubbers. These are intended to absorb 5 transmission shocks and drive chain snatch. If the rubbers are worn or deteriorated, or if the sprocket hub is a loose fit in the rubbers, renew them. Renew the 0-ring around the left side bearing housing if it is installation. 10 Apply a trace of grease to the brake shoe pivot pin and to the operating cam. Refit the cam, followed by the felt seal Note that the felt seal should be renewed if damaged, and should be soaked damaged. 6 Check the wheel bearings by turning them with a finger as described above. If the bearings are worn drive out the old ones and fit new ones after packing them with grease. The general procedure is similar to that described for the front wheel bearings in Section 5. 14 Rear brake - Inspection and overhaul Warning: wtiichi is friction material contains asbestos, inhaled in dust form Wfien working on tfie brakes, wear a dust mask Do not work in an unventilated area and do not use compressed air to clean brake dust off the brake parts dangerous Bral