Typically, if I’m doing an after-work ride that doesn’t involve hill, speed or power work, I spin in the lower 90 rpm range and average about 17 mph. But on a ride last week, I rode in a lower gear combo for an hour that had me spinning right at 100 rpm the entire time and still averaged 17 mph. I did this intentionally just to see what the ride would be like and felt good and wasn’t bouncing up and down.
For a given speed, can you spin too fast (assuming you’re not bouncing all over the saddle)? Is riding at 100 rpm in a smaller gear better than pushing a slightly larger gear and riding at 90 rpm?
not sure if you can pedal too fast, especially on a recovery type ride, but certainly optimal cadence is not the same for everyone. I think i recall hearing massimo testa saying ideal cadence on average for most pro cyclists was in the 90 range, not the lance armstrong like range (although that may be optimal for him)
so in other words, this question i hard to answer, not knowing wattage, hr, and other factors.
Take this bit of physics with a grain of salt, but to illustrate the concept: if you got rid of your chain and just spun you would exert some energy but you’re not going anywhere. Moving your legs, feet, pedals, etc. in a circle requires some, let’s call it “fixed,” effort that is added on to whatever effort is required to achieve forward movement. So, at very high rpms in a very easy gear, the “fixed” component of your effort is high (relative to the force on the pedals that moves you forward) and things get inefficient. So, yes, there is a cadence that is too high.
I suspect a simple experiment (which I have not done) would prove the point – put on a HRM and go 15 mph (or whatever the max you can sustain) on flat ground in your easiest gear. Then shift to one gear (or two) harder and maintain speed (obviously dropping the RPMs). I assume your HR would drop.