Sōichirō Honda - 本田 宗一郎17-11-1906 - 05-08-1991
If you don't have a "secret key", then you do not have to enter anything there.
Tagged in 1959, c100, poster
A page from the 1959 Honda C100 Ownersmanual / Parts list that is in our library. It nicely shows the electrical components.