Originally Posted by Machka
Wouldn't your example be a difference of 20 psi?
However, I only inflate my tires to somewhere between 90 and 100 psi at the best of times anyway.
I didn't state it very clearly. The difference was the atmospheric pressure. It went from 15psi to 5psi, hence the 10. The presure in the tire doesn't change at all since no air is going in or out.