I think this largely depends on the tire's "side surface" as well. For instance, my motorcycle's tires are not race tires, but street tires. The bottom of the

I think this largely depends on the tire's "side surface" as well. For instance, my motorcycle's tires are not race tires, but street tires. The bottom of the tire only goes up the "side" for a limited distance. If I lean too far the side of my tire no longer touches the ground Also, the lean angle would have to be related to the foot peg size. My current foot peg is quite long--even for mild lean angles somestimes I can feel the road scratching on my boots and the foot peg.