rruff wrote:
FindinFreestyle wrote:
I find it somewhat nonsensical that you think there is a massive range of positions where power, comfort, and aerodynamics are largely the same. But maybe there is something to that as well. I can float with the idea.
Just my experience. And I don't think I'm that unusual based on what I've heard from others.
I'm always fiddling with it. I recently got a new frame and bars so I could *really* fiddle with it. I was surprised that moving the bars up 10cm and back ~15cm is giving me the same aero drag. Is that a big range? The lower torso position is the same in both. The upper torso is a little higher (no longer tilted down) and the way I hold my shoulders is massively different; scrunched and pulled up to my ears rather than stretched down and in. I haven't raced in the "scrunched" position, but I'm pretty sure it wouldn't be an issue for 40k. It could even be better.
That's just a single example. The subtle and not so subtle perturbations one can make to their position are infinite, and the effects of each change on drag and sustainability are all over the map (individual differences). If you are a good fitter and are good at coaching the client during the fit, then I believe you can put them in a very serviceable position. But I wouldn't call it optimal. To find optimal (+-1%) I think I'd need to spend at least 1000 hrs in a wind tunnel. And there would still be new things to try...
I know you are a pretty high end time trialist, and a fiddler, and I think those two things go hand in hand. We're sorta talking about two different things though. I used to personally field test (VE) a lot to achieve the position in my profile and go 51 low in a 40k. But what we do personally is not super informative for what 99.9% of triathletes should be doing to get 95% of the way there.
I certainly believe that up and back 10 and 15cm was roughly equal for you, but extrapolating that into what you are claiming is a stretch. For most people that walk in my door, lower is generally faster. Of course there are caveats to that. Of course we want the head low, relaxed, and turtled. I generally want the elbows pretty narrow. Those things go without saying. But while 10cm up and 15cm back may both be equally aero and comfortable enough to ride, I'd wager that 99% of those I fit in the context of a controlled fit bike setting are going to choose one of those vastly different reach options as clearly and unequivocally more comfortable, and they should probably have that. And most of the time positional changes of that magnitude are not going to have equal drag.
You're experimenting in the realm of radical positions, and you need to be in that realm to find the last 1%. But you gotta keep it in perspective.