Hi,
There is a lot of public information on aero gains when comparing wheelsets, handlebars, helmets, clothing etc but I cannot find any aero-tests between different groupsets? I would guess that both hood shape and hood placement would influence a fair bit?
Adding up all the different shapes of a groupset I would guess that it differs between the major brands. Anyone seen some testing done on this subject?
And yes I understand that it is negligeable in comparison to positioning on the bike etc but still…
We look up the weight and compare a few grams between groupsets and estimate power loss on the smallest cogs and discuss chain lines for efficiency. - Where is the marketing hype around areo-groupsets? 
No, and I wouldn’t worry about this. With things like hood shape and button/lever placement, ergonomics is much more important anyway. E. g. on a road bike I vastly prefer the ergonomics (including hood shape) of SRAM compared to Shimano and Campagnolo. (On the mountain bike either is fine.)
Moreover, the moving bits of the groupset are exposed to very turbulent air caused by your rotating legs, so I don’t think aero design matters much in that area anyway.
Oh, you never know! The levers are on the leading edge of the bike so they can have outsized influence.
I helped a recumbent cyclist with his aero setup. He was set up shimano brake levers coupled with bar end shifters. I put telescoping shrink tubing around the leading edge of the brake lever & cable so that it was seamlessly integrated into the bar wrap. That was a big savings & IMO it looked better (although it’s hard to say that goofy bike could look good).
So it can make a difference. I’ve always wanted to fiddle around with handlebar ‘mittens’ to improve aerodynamics…I think there could be something there…just would have limited application due to rules.
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I’d be willing to bet that a track group set will be the most aero.
Being facetious aside, I’d guess that the new sram hoods with the 1x setup would be, though I’ve never seen a comparison between group sets. I think I heard that someone has shared the benefits of 1x on aero and it was a couple watts though.
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Exactly! I mean there is aero comparisons made on the drag delta if you wrap the tops on your handlebar or not. Hood design must influence a bit. - I think I am mostly disappointed that there are no data around it to nerd out on
@tlarsson when I help a rider aero up their bike, the first thing they do is take a couple laps in the base setup, and then take a couple laps with ‘the stick’. The Stick is just a tennis ball taped to some PVC pipe. It helps us know that we’re taking good data vs the baseline but also serves as a basis of comparison.
If you can get ‘a stick’ improvement in your aero setup, that’s wildly successful.
The brake lever change pictured above was a ‘1/5th stick’ improvement. That’s a big improvement.
And, of course, no triathlete would ever think hand, arm, elbow placement wasn’t critical to aerodynamic performance. So your intuition is most likely correct. But the rider’s interaction with the hoods/levers is very important. Which is why I think putting that whole package (hand and lever) behind an ‘aero pogie’ is probably a winning idea.
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Think its because the most interest in aero properties is in TT bikes, with very different bars/brakes setup.
