Originally Posted by
Mista Sparkle
Sounds like you are riding a fixie...
Nope. Further comment below.
Of course, speed and cadence needs power, of course find what is comfortable, but if you spend a lot of time at <70
and are working, you may want to try a higher cadence, it may work better for you... or maybe not.
https://www.bikecalc.com/speed_at_cadence
The part you yourself bolded is why my cadence depends on my level of effort. If the effort is low, then the percentage of my muscle strength required to turn the pedals can be low even at a low cadence, and if the effort to turn the pedals is already low, there's not only little point to spinning faster, it can actually be difficult to do. I mean, I'm sure you'd agree with this, but for anyone who might be confused, try to spin at 90 or 100 rpm while doing 5mph in your lowest gear on flat road and see how that works out. With no resistance at all (or very little resistance at all) spinning is difficult and unnecessary. The reason I'll spin ~80rpm at 17 mph or 85rpm at 18mph and 90rpm at 19mph (or close enough, just an approximation here) is because the level of force required per pedal stroke will be approximately the same. If it gets too easy I'll shift up to a higher gear, if it gets too hard I'll shift down to a lower gear, as the case dictates. The cadence is meant (at least for me) to keep the required leg muscle exertion to a level that's sustainable over a long ride.