Originally Posted by
jonathanb715
Sigh. When measuring circumference or rollout, you are measuring from the same point on the outside of the tire to the exact same point. That point does have to cover that flat part as the tire rolls through.
Except the flat part moves relative to the tire. Your entire premise with the increased length of the contact patch is wrong because the flat patch is always in contact with the ground. It is stationary relative to the ground, not relative to the tire.