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Old 04-20-2011, 08:16 AM   #38 (permalink)
CapriRacer
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Quote:
Originally Posted by justjohn View Post
Hahah. I read it. I just don't get the part about load capacity going up by a greater percentage than tread and how that translates to lower RR.
The load carrying capacity of a tire is directly tied to the internal volume of the tire.

If we take the example of a tire with a 100% aspect ratio (because the cross section is a circle and that's easier to visualize), then the volume of the torus (the shape of a tire) is a function of its cross sectional area.

The area of a circle is pi* r-squared. If the radius is increased one unit, the the area is pi* (r+1) squared = pi* (r+1)*(r+1) = pi*(r squared + 2r +1).

It's that 2r term causes the area to go up faster than the increase in r.

Tires are oval in cross section, but that only makes the formula more complex. It doesn't change the fact that the width is squared to get the volume.
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