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wheels . If the machine is tilted so that it lifts the right wheel , for instance , from the ground , there will be an increasing bias toward a right turn , as the left rear tire picks up load , and the right rear tire relinquishes load . As frictional force between the tire and the ground is a function of applied weight , the right rear wheel loses frictional force allowing it to slip , thus facilitating a turn . The front wheel , as it is pointed to the right by use of the handle bar , completes the process of pointing the machine to the right . The process to execute a turn requires the rider to exercise a sense of balance as the forces which are applied to cause a turn , and the forces which result from executing a turn , work in concert to overbalance the machine such that the c . g . approaches a position directly over the axis of contact with the ground . At this point the machine has reached an unstable equili brium . The rider must continuously shift weight and the handlebar angle to maintain balance and execute the turn at the same time . Straighten ing the handle bar tends to bring the right rear wheel down as it reduces the magnitude of the centrifugal force by reducing radial ac celeration .

The motions involved in executing a turn as described above are quite dissimilar from those involved in turning a motorcycle . Without going into the mechanics of a two - wheeled turn moore deeply , the process of turning involves leaning in the direction of the turn . An ATV rider accustomed to two - wheeled vehicles may have some difficulty initially in overcoming ingrained reflexes in order to lean to the outside in turning the ATV .