Carriage House Plans: Tire Size Calculator

Thursday 10 January 2013

Tire Size Calculator

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Tires flex with inflation and load, meaning with bigger load the same tire is going to have smaller rolling diameter. Than at speeds the centrifugal forces change the rolling diameter as well.

That didn't matter in the past, but now ABS, traction and ESP systems are having speed sensors at each wheel and when one tire spins with different rpm, it will take it as lost traction. Usually the systems give you 3% tolerance before kicking warning lights.

So if you are matching different tires, you have to go to the tire data sheet and read the rpm. The manufacturer doesn't matter >>> all of them manufacture tires with pretty loose tolerances