Re: 50cc GY6 on a Bicycle??
Ive got a 150cc GY6 chinese clone on a Roketa china scooter, Ive thought about a stretched out bike build with one myself but dont know if I'll ever do it or not, the 150's with some mods like mine have a lot of torque and my scooter will cruise @ 63-64 mph on the flat without anyone head wind, for a 200+lb scooter pulling a 215lb man than just aint really that bad for a cvt drive 13" rear wheel.
Id think a 50cc like was mentioned would be a better engine for a bike build and then maybe mod it with one of the inexpensive 80cc kits for an excellent powerplant, all the GY6 engines ive been around are gas sippers also, I have got around 80+ mpg on my scooter if I dont run it down the road at 6500-7000rpms to much.
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!