[Jim Allen]

Originally Posted by CapriRacer

Jim,

That is an interesting way to measure circumference.

Let me put it this way: I would think that load / inflation pressure effects would be greater than the effect caused by centrifugal forces.

Capri: Is that,
"Interesting, that's the dumbest thing I've ever seen!"
or
"Interesting, cool way to do it!" ( : < )

Either way, it's not my idea. It's how the programmer wanted you to find the circumference. Easy to do. I though it was cool. My other method is to measure the loaded radius with the tire inflated to the pressure I will use.

If you have other methods, would love to hear about them!

As to centrifugal forces, a tire engineer told me regarding one particular tire (a big, high profile, 38 inch diameter, 15 inch rim, mudder) that the tire grew in circumference by several mm at high speed (he did not define "high"). I never did get to question him further to see if this was a general phenomenon, or something found just on that tire, or others like it. That's why I asked you about it.