Originally Posted by
dougmc
Actually, the contact patch size doesn't really vary much based on the size of the tire. What matters is the air pressure -- 220 lbs of rider and bike on 110 psi tires = 2 square inches of contact patch total (between both tires), whatever the size of the tire.
Which is about what you said, but if the rider + bike is 150 lbs, the contact patch is about 1.4 square inches total.
Of course, on most upright bikes, most of the weight is on the back tire, so the back tire has a larger contact patch ...
Small tires don't deal well with potholes. That's a strong argument for larger tires on any bike.
Absolutely. But size of the tire is only one of many factors that go into that load rating.
I think you`ll find the contact patch of a 50-622 closer to 2.5 square inches per tire. Which is the only reason they can run 55PSI and still handle a 220lb load. And also the reason they have MUCH more effective braking performance than a skinny tire, regardless of the kind of brakes used.