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Old 12-02-07, 01:52 PM
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Roody
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Originally Posted by Rincewind8
The ideal gas law is:

pressure*Volume = mu(number of moles of gas)*R(Universal gas constant) *Temperature(in Kelvin)

Assuming the volume stays constant, p/T has to stay constant. So filling the tires at ~266ºK (20ºF) to a pressure of 102psi and then heating the air in the tires to room temperature of maybe 297ºK (75ºF) results in a pressure of 102psi*297/266=114psi.

Since there is always a safety margin, the tires should hold that pressure
.
How big is that safety margin?

The way I'm reading it, the tires are only rated for less than 85 psi, so he's already over-inflating them. It seems like the extra 12 psi could blow them off.
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