Originally Posted by njkayaker

???

"Tire radius" (in my illustration) is the radius of the part of the tire that isn't at the patch on a loaded wheel.

Tire radius > patch radius (as the illustration shows).

This radius is going to be very close to the radius of an unloaded wheel


??? It seems it would be harder to load the bike and take that measurement. You'd probably need two people.


?? I said this.


??? This is what the illustration is showing. The effective radius of the tire is irrelevant. Only the patch radius matters.