Originally Posted by Rolla

Lennard Zinn puts it this way:

"There is no question that if a rider climbs at constant speed, it doesn’t matter where the weight is located on the bike. Extra mass could be concentrated on the pedals, at the rims, in the frame, or in the hubs, and as long as the bike’s total weight is the same and it has otherwise the same characteristics, it will create the same resistance to the rider’s efforts.

That said, there is also no question that it takes more energy to accelerate the same amount of mass if it is located out on the rim as if it is located at the center of the wheel (or on the frame)."