Originally Posted by
Doge
I am not aware of all that data those links cite. The data I have seen is TT and lab based, not riding in a pack based. That would be hard data to get I expect, but my guess is it is being calculated / guessed. The pros have gone aero 50mm profiles generally over 30s and over 80s. Add some gusty side winds and those different profiles can really be felt, contrary to what those slowtwitch articles were saying.
josh pertness knows his stuff and is pretty transparent. those posts were from 2 years ago and some things have changed.
basic message -- and it is a bit different for true pros v amateurs -- is that these guys don't have to choose between light and aero due to the 6.8kg limit......so "light" is pretty dumb for them. there are a few circumstances (for amateurs) when it matters, but even those are rare. (uphill only and even then above a certain grade.)
agree that handling comes into play, and it could be that the 80mm profiles are just enough heavier that 6.8kg becomes a bit harder to meet with them. those profiles can be a handful in certain winds and descents (IME), and could result in slower times despite being more aero. ~50 with modern rims is pretty much no big deal, even in the mountains (descents)...and i'm just a hack.