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Old 02-23-2016, 07:05 PM
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Tony01 Tony01 is offline
Motorized Bicycle Elite Member
Join Date: Nov 2012
Location: San Jose, CA
Posts: 612
Default Re: My electric start full suspension predator 212 build

Oh. It was a 3.5hp flathead. almost double the displacement as the 79cc but only .5hp more.

Try a 9 or 10:1 then.. 9 might be a little tall as well.. it depends on whether you want to turn high rpm's and accelerate better or turn low, pedal assist, and have a good rpm on your cruise..

multiply your engine rpm by the MPH-wheelRPM number .077xxx and divide by your gear ratio, that will give you the mph per engine rpm for a 26" wheel.
I don't always listen to Alice in Chains..... but when I do, SO DO THE NEIGHBORS
212cc 2-speed
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