Originally Posted by
gsa103
Yes, but in general bigger riders have an advantage in time trials. If you look at the top time trialists they are all larger riders, the ultra-light climbers get smoked in time trials. It's power/CdA that matters. A rider who is 20% heavier, might only have 5% higher CdA, while making the same W/kg.
If your average power was the same as his, and he's significantly lighter, he's just in much better shape than you are.
I'll disagree about a couple things and on one thing I'll agree. (1) Bigger riders don't generally have an advantage in time trials that traces to their size. The bigness or smallness of the rider doesn't matter (apart from the drag surface area). It's the POWER that makes the difference. And bigger riders often produce more power. (2) It's not the Coefficient of Drag that matters when the surface area is so much different. In over-simplified terms, total drag is the real key and total drag is coefficient of drag times surface area. Even if our Coefficients of Drag were equal, the fact that my surface area is so much larger would still make me a lot harder to push through the air. Indeed, I could have a significantly BETTER Coefficient of Drag and, because of the vastly greater surface area, still be harder to push through the air.
As for agreement? The two of us produce the same power, but not the same power per Kg. Pound for pound, he produces more power than I do. But then, he's a Pro1 and he's half my age. He's probably in better shape by most measures -- and should be.