Quote:
Originally Posted by RedDevil
No problem, glad you take it sportingly 
IIRC someone already tested whether higher tire pressure influenced the circumference and rolling distance, and it did not noticeably.
The steel belts keep the tire at the same diameter.
From my own experience: When I discovered Ecomodder shortly after buying my Insight I raised the tire pressure by almost 10 PSI, and I was curious whether it had an effect on my reported commute distance. But it didn't; the speed bump from my example remained right there at 5.0 (at that time).
To graphically demonstrate the tread shrink effect (and my lack of drawing skills  ) I made this conceptual picture of a treaded tire:
As you see, when the contact patch is flat the notches align and their height becomes irrelevant to the distance between them. |
Now take those red boxes and imagine them at half their height. Is the distance from the axis greater or lesser?