Stupid idea!!! + -

[Cannonball3]

Its a balance between the reduction and the roller. Raise the ratio to a higher gearing (lower #) and you can decrease roller size. Its probably easier on a scooter to a smaller roller direct. The 62cc will easily run a 1.5”, may get as high as 35 mph with a nice cruise in the low 20s where you want to be. The 62 would be much quieter in that range.

I had a 43cc 2stroke that easily broke 30 on a 1.5

 

[Chainlube]

Its a balance between the reduction and the roller. Raise the ratio to a higher gearing (lower #) and you can decrease roller size. Its probably easier on a scooter to a smaller roller direct. The 62cc will easily run a 1.5”, may get as high as 35 mph with a nice cruise in the low 20s where you want to be. The 62 would be much quieter in that range.

I had a 43cc 2stroke that easily broke 30 on a 1.5

My limitations are the trans I have on the engine. It's a little centrifugal clutch with a 6 tooth drive sprocket, and my wheel sprocket (regardless of roller) is a 44 tooth sprocket. That reduction has to remain constant. The roller isn't finalized yet and I can make it from a few different bits that I have lying around.

 

[Cannonball3]

An 8” roller will give 22+ mph at 7500. Maybe something like a lawnmower wheel?

 

[Chainlube]

An 8” roller will give 22+ mph at 7500. Maybe something like a lawnmower wheel?

I was thinking of peeling the rubber off the scooter wheel and just using the hub which is 4". That would make a nice size roller don't you think?

 

[Cannonball3]

4” would only be good for 12mph at 7500. Your reduction is only turning the roller 1027 rpms at 7500. At that reduction speed will only come from a large roller. I think 8” minimum.

 

[Will'smotobikes19]

I found maybe one of the biggest 76mm clutch motors they are mostly augers, I think there's a kasei 72cc as well.

82cc Post Hole Digger Earth Auger 100,150,200mm Drills 4"6"8"Fence Borer Spring | eBay

Horti Power HP822-206 82cc earth auger is superior quality and incorporates the latest technology, including a 3400W 2-stroke engine to provide maximum torque with minimum effort. The coated handlebar grip provides maximum leverage, ideal for landscape professionals and tree specialists.

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