Originally Posted by
Retro Grouch
I think the part a lot of people have trouble understanding is how rider strength and power enter into the equation.
They don't figure in at all. The calculation is for a specific cadence. If you can achieve that cadence (say 90), then you will go that speed. Now, it is possible that you may not be ABLE to achieve that cadence in a specific gear combination because you aren't strong enough. Maybe you can only do 70 RPM in that gear up the hill. Yes, you will be slower than the person who can spin 90 rpm in the same gear. It doesn't mean the equation is wrong.