Weedeater belt drive

[5-7HEAVEN]

A simpler, cheaper way would be friction drive. Mount your engine above the rear wheel. Install a 3/4" deep socket onto the engine shaft. The socket will spin on the top of the rear tire.

Your engine will buzz and your bike would fly, and you can still pedal.

 

[MEASURE TWICE]

I'm not positively sure, but I thought when I was using a 1.5 inch pulley that it was too small to have enough surface contact with the belt to not slip under loading. The loading of that small diameter pulley I see on drill presses as one of a few and it is the smallest. The kind of power transfer is magnitudes different than moving the weight of a person and the bike and motor up a hill. The reason I am not exactly sure, was at the time the rear wheel sheave had a manufacturer's weld bump not smoothed out. It was where the pressed stamped steel, or extruded metal was bent around and butt welded. That weld bump when I Dremeled it out smooth made all the slippage go away. But of course also at that same time I switched to toothed gears for that section of the transmission. I still use a belt with the Sheave to the rear wheel, but the adjustable diameter pulley I have set around 2.5 inch.

 

[MEASURE TWICE]

A simpler, cheaper way would be friction drive. Mount your engine above the rear wheel. Install a 3/4" deep socket onto the engine shaft. The socket will spin on the top of the rear tire.

Your engine will buzz and your bike would fly, and you can still pedal.

I am intrigued by the friction drive idea. Some people have on this site posted about various way doing that. Also there was a discussion on how to make slight changes to the drive that presses on the tire, like knurled or smooth metal or other material for best grab.

MT