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Old 01-22-2015, 11:01 AM
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mapbike mapbike is offline
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Join Date: Mar 2010
Location: Central Texas
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Default Re: Top Speed, 80cc Chinese motor? what is the record?

Originally Posted by Davezilla View Post
Just ran the calculation for mine... to go 41mph with the 44 tooth sprocket and 26" wheels it comes out to 9350 rpm...
According to the calculator I was turning 8,950 RPM @ 52 mph on the bike with 24" wheels and a 30T sprocket

On this engine I did good port cleaning, used two base gaskets, deck not milled so compression wasn't as good as it should have been, piston had ramps at transfers and exhaust, piston had 12 3/16" holes drilled in skirt to lighten it a little, engine had Puch Hi Hi 70cc head and home grown free flowing exhaust, no expansion chamber and RT Carb.

With the jug shaved down to get compression up I'm sure I would have gained a few extra MPH and it would have got there quicker.

Thanks for digging this up Dave
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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