Sprockets, RPM and power(bands)?

Dokroma

New Member
Aug 29, 2021
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Hi,

I saw a comment on a youtube video and I stupidly did not save it. I think it was talking about how going too low of a sprocket size or too high did not let the engine go to a certain RPM or a power band or whatever, I'm not quite sure. All I remember is that I should have saved it because it was very technical information. Can someone explain the relation between sprocket size, RPMs and power for me?
 
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curtisfox

Well-Known Member
Dec 29, 2008
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minesota
If gearing is to high it pulls to hard and wont let it rev up to power band, Some guys try to small of sprocket for more speed and pulls to hard, if you don't have the proper tuning it can't pull the smaller sprockets..........Curt
 
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Greg58

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May 1, 2011
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Newnan,Georgia U.S.A.
I have a 48cc engine on my black bike with a expansion chamber, it will run 30-32 with a 44 tooth sprocket, I changed to a 41 and lost top end speed. I've learned from trial and error that the smaller engines need to rev higher to produce the power, I have a tach on one bike with a 48cc and get 7500-7700 rpm.