Originally Posted by
CardiacKid
I am not a physicist, but I don't think bigger tires would help except when you hit a bump. There is going to be the same amount of weight on the wheels, regardless of the size of the tires. In fact, there is going to be more weight on the wheels with bigger tires, because the tires weigh more. Additionally, the contact patch is going to be shorter and wider, with the wider tires. I would think this would focus the weight onto a smaller cross-section of the wheel. As Tom pointed out, tire size will have no effect on torque.
This seems to be intuitively wrong, but intuition and physics don't ever seem to get you to the same place.
Bumps, potholes, etc are the major source of stress on a wheel. If us clydes only rode on perfect tarmac, we wouldn't need very strong wheels at all. When we nail a pothole, the stress on the wheel is far higher than that sustained by just our body weight. If I could ride on perfect pavement, I'd be able to get away with 18 spoke weight weenie wheels, instead of 36 spoke 3X Deep Vs.