The BEC boys on Locost seem to like the 3.38 diff, I know for a fact that the 3.9 is to low, the 3.6 gives a top speed of 110 on most bike engines and by then its screaming like a nutter( dont forget the bike gearbox has a drop down ratio built in) and most bikes have rear wheels that are 20" diameter.
Some bigger bike engines ( the ones that rev to 10,000) are OK with a 3.6 but you are still screaming all the time.
Fit a 3.6 for IVA then find a 3.3 at your leasure
|