Here's the new requested pics, Friction

I finished a new adjustable rack system designed to fit different gas engines and an electric motor. Here's the pics. The engine on the bike is a 2.4hp 81cc, bike cruises at 30mph with 190lb rider.


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Great pics, nice bike, thanks for sharing.

A close-up on the the roller assembly would be cool.

Did you make the adjustable rack mount yourself?
Yes that roller assembly is amazing. What roller? Is it a small rim? Is it bolted on to the sprocket? Where does the sprocket come from? How many teeth on the clutch and on the roller?

This is cool. So cool.

Thanks for the pics!
The roller is a small rim. I at first made one with the standard steel roller, high speed bearings etc. But this set up worked better and it's super quiet, as is the engine, being it a 4-stroke. The sprocket is welded to the rim. I think it's 12t/20t (about) I had 12t on both at first, but the bike was waaaayyy too fast.
looks a little heavy in the rear.the rim roller would try and spin more tire on the bigger part of the rim than the smaller part of the rim.will that cause wear?