Originally Posted by ProDigit
I'm not really into performance, but MPG.
I don't mind if I have to help out the engine by pedaling from a stand still. The engine basically just has to push the bike and myself (a 6'3" 170LBS individual), over a flat surface, with slow to medium acceleration.
If you have a 66cc, you'll be fine with 40 tooth and still hit 40mph. 66cc chinese engines are wayyyyy underestimated. It'll even take 29tooth and still get you up hills as long as they're not that steep