When a bike hits a bump going up, say a curb, clearly, the bigger the wheel: the less pronounced the jolt to the rider. Or more correctly, the upward acceleration is less rapid with a larger wheel. (As an illustration of this concept, consider a very large wheel and a very small wheel as they encounter a curb. A very large wheel would move to the higher altitude of the top of the curb, but the transition would occur over a distance, and, consequently, over a time. The very small wheel would also have to move to the higher altitude, but over a shorter distance and time. ) But what about going down off a curb? Does a large wheel confer any advantage in that situation?