OK, here's what I'm getting from the various responses. Although the larger wheel travels farther on one revolution, the energy required to turn that larger wheel one revolution is greater. On the other hand, in order to travel at the same rate of speed as the larger-wheeled bike, the human motor must turn the cranks on the smaller-wheeled bike at a faster cadence.

If you have two bicycles with differently-sized wheels traveling at the same rate of speed, the motor turning the larger wheels will apply energy to push that large wheel one revolution, while the motor that turns the smaller wheels will apply energy to turn the cranks at a faster cadence. In other words, both cyclists are expending the same amount of energy to perform the work of traveling a certain distance at a certain rate-- one to turn a larger wheel, the other to turn at a faster cadence.

is that correct?