Originally Posted by
chaadster
Correct, but I was making a simple point that output is not steady, and underscoring the fact that climbing performance (or let’s call it RPC(limbing)E) is, for most riders probably affect by feedback through the bike, i.e. as has been discussed, how the bike feels.
It is the same point
jayp410 postulated when they wrote, “All that said, there could be secondary effects from wheel weight which contributes to how quickly a bike (or rider AND bike) can climb. A rider could be more efficient in delivering power if the wheels allow quicker accelerations, due to biomechanics or some mumbo jumbo that is nearly impossible to quantify except by testing, and it may vary by rider physiology and/or technique. With heavier wheels, the duration of the downstroke in which more force is applied could be lengthened, and the tire could deform more (over a longer time per pedal stroke) with heavier wheels, which could increase rolling resistance more while it's deformed.”
Well you have picked up on the only vague and speculative part of that entire excellent post! Mathematical models predicting climbing performance for a given rider power output, bike and hill profile are accurate enough without resorting to modelling micro-power/accel variations during pedal strokes or rotational moments of inertia of wheels. As far as I am aware none of them bother to do that simply because it doesn't affect the end result. It all averages out over any reasonable time frame e.g. a 3 second rolling average is enough to show a reasonably smooth power output when riding along attempting to hold a specific power level. For example if I target 250W for a long steady climb I can hold that power level quite easily within +/-10W with a 3-second rolling average filter. It only starts to look lumpy with a 1 sec averaging filter. Those micro-accelerations/decelerations during the pedal stroke have an immeasurable affect on my speed profile when climbing. It's not like a full bore sprint, where you really are accelerating your wheel set through a meaningful speed range that might actually make some difference to the total work required. Even then it's quite a subtle effect in the overall equation.