i think you could grind down the clutch ,and weld a sprocket or a pulley ,,i would go with a very small steel pulley ,then you would have to buy a very large pulley ,,lets say your back wheel is 26 ,, then you would want your back pulley to be 18 or 20 in. dia depends on size of motor , , power saws very big time from 2 hp. to 7 hp. the rpm of most saws does not very that much
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,, now it all seems quite simple if you could find away to mount your saw on the back of your bike ,, only one problem your pulley has to be on the same side as your sprocket of your bike if you plan to go forward ,, if you mount the pulley on the other side theres a much better chance that police would pull you over if you were going 30 mph in reverse ,,,
my advice is if you don"t have access to lots of machine tools i would not attempt it , ,i would save my money and buy a 70cc kit or whatever ,,it will be faster and cheaper in the long run and a very good chance it will save you on shoe leather ,(pushing your bike home )
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