I remember discussions from years ago when a group of physicists came to the
conclusion the the wheel actually hangs from the bead of the tire.
The bead is the area of contact between the tire and the wheel. That's
where the upward force of the tire is acting on the wheel. The bead is very
strong, and nowadays has steel cable in it. The wheel is essentially
hanging from that cable.
Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Bluffton University
1 University Drive
Bluffton, OH 45817
419.358.3270
edmiston@bluffton.edu