Originally Posted by kf9yr

As I look at the original post I see 3 statements

1. I agree a heavier wheel with more weight on the rim is harder to "wind up" as there is a higher moment of inertia. This also works in reverse when you're braking. I have a 1200g set of carbon wheels that I can absolutely feel accellerating easier from stoplights than my much heavier Ultegra wheelset. This wouldn't make much of a difference in a TT but when you need to accellerate and decelerate or climb a lot I don't see how it can't make an improvement, especially on a long ride.

2. More weight at the outside of the wheel would of course make more of a gyroscopic effect but it would be felt more on a downhill as the rotational speed of the wheels is much slower on the uphill than on the downhill. I would go with the lighter wheels for climbing as I wouldn't have to pedal the extra weight up the hill.

3. If the weight around the circumference of the rim wasn't very close to equal you would have quite a scare on a fast descent. There isn't any weight redistribution going on or the wheels would feel like they were trying to buck you off at 40 mph.

If there wasn't a discernable, measurable difference with lighter wheels the pros wouldn't all be riding on them during their races.