Thread: 24 m.p.h.???
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Old 12-02-2010, 12:44 PM
Nashville Kat's Avatar
Nashville Kat Nashville Kat is offline
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Location: Jacksonville, Florida
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Default Re: 24 m.p.h.???

It could be a little of both- and the wider tires.

I have a little formula when thinking about wheel size- just a quick approximation of percentages-

If you think about a wheel, say a 26" - then there are four factored to 100-

so any 1 inch change in size is roughly equal to a 4 % change,

the dif between 24" and 26" is 2 inches, or roughly 8% then-

so then you can expect an 8% gain then in changing from 24 to 26, (or 12% to 27"), it's like putting on a sprocket 8% larger

For sprockets:
Then, since there is (even more roughly) a three factor for the sprocket (3 x 33 teeth)
a change of a tooth is a roughly 3% difference in either direction-
3 teeth makes about a 9% dif

so if you went to 26" wheel, you get 8% gain
and if you went to 36 instead of 40 teeth (4 x 3%) you get 12% gain-

and so with both these things you get approx. 20% gain in top end gearing

your 24 mph now (aprrox 4 to 100) is increased 4% with every mph- 20% would be 5 mph- roughly, on paper, at least

Wheel width and total weight are not so quantifiable, but I've found great dif in wheel width especially

and then there is engine performance.

Last edited by Nashville Kat; 12-02-2010 at 12:49 PM.
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