In australia motorcycle engines are legal upto 450cc and the transmissions are legal too, 5 or 6 speeds. Although it would be better to narrow it down to 3 gears which most people recommend to do even with the lawn mower transmissions like a peerless, etc. Iv heard guys say you choose a gear ratio that will make it so you only need to use 3 of the gears, How would i work out or choose a ratio to do this? as id really like it if it were possible to setup that way.
cheers guys
snyds