if you want physics, then it's inertial mass, or I. I increases with
radius/diameter and also is greater when more mass is further from the
center; therefore fatter wheels have more I. when you spin a wheel it's
got various forces acting on it. some of these are perpendicular to the
plane of rotation and therefore resist when the wheel changes plane, or
wobbles. since those are forces, then velocity is also a factor.
therefore, tall tires, fat tires, and fast tires (or riders) make less
wobble. but that's only the textbook answer


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ubersquish
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