Aero wheels and upright riding position

I would think that aero wheels like anything are marginal. maybe you can bridge a gap now that you just couldn’t quite cover before, or recover just enough on a fast flat to hang on over the next roller. Its possible that it could make a results difference of a few places or a minute or two in a race I would think, but no, it won’t change you from midpack to contender or anything. Id say aero wheels probably are good for 5-8 watts off your NP for a race on average, and how hard do you work to get 8 watts on your FTP?

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You get a lot more aero advantage per dollar spent by getting a nice aero helmet, first of all. You can get an aero lid for a few hundred vs $1000+ for an aero wheelset.

You get a lot more aero advantage per dollar spent by getting a nice speedsuit, second of all. you can get a good speedsuit for a few hundred as well.

And, finally, you will get just about the same aero advantage from deep section or tri-spoke wheels whether you ride upright or with your trunk in a horizontal position.

You know, one more thing: if you don’t have aero spokes, that’s a pretty cost effective way to aero-up your wheels. For the first 60mm or so deep section rims improve aerodynamic drag pretty much linearly with reduced spoke length. The linear velocity of spokes at the perimeter of the wheel causes more drag than you think if those spokes have a circular cross section. That’s why deeper rims improve wheel aerodynamics materially but wider hub flanges, not so much. So if you have just regular spokes, that’s something to think about.

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It might not turn on at some “magic speed” it does however (insofar as I understand it at least) get exponentially more significant as speed increases. This means that aero gear saves both a greater absolute number of watts and a greater relative (to total power output) number of watts at a higher speed as opposed to a lower speed. Slower riders are not thus the recipients of greater aero savings.

You are leaving out time. Supposedly.

Anyhow, I think the best order business is to focus on fitness, likely cheaper. Aesthetics can be compelling though. :star_struck:

There is a lot more to life than money. When I sit around with friends we might talk about wins, making breaks, bridging gaps, PB’s, KOM’s, but none of us talk about how rich we are (or aren’t). Life is short, dropping cash on marginal gains may not be practical but that doesn’t mean it doesn’t matter :+1:

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Below is an excerpt from a Cycling weekly article that basically sums up better than I can at what I’m trying to get at:

I asked Dr Xavier Disley, director of AeroCoach, whether it was more important to save drag or increase power.

“In a strict one-to-one [ratio] scenario, saving 10 watts in aero drag will increase your speed by the same amount as pedalling 10 watts harder,” he says.

“The first thing to note is that your aerodynamic drag wattage savings are scalable to the speed that you’re riding at.

“The higher the rider speed, the more impact small changes in your own aerodynamic drag – called your CdA – will have on wattage you save.”
“At very high speeds [above 34mph], tiny changes in CdA/aerodynamic drag will have around 1.5 times the impact they would have at 25mph. So aerodynamic improvements net a greater wattage saving.”

This might lead to the conclusion that aerodynamics is of interest only to faster riders. But you’d be wrong.

Slower riders are out on the course for longer periods of time and wind hits them at a wider range of angles.

“Even a one watt reduction in drag over an Ironman course at low speeds can equate to up to a two-minute time saving,’’ says Disley.

So if aerodynamics is a concern for both slower and faster riders, who should be paying more attention to improving their power?

A highly trained rider will find it far more difficult to increase their sustainable power output by 10 watts than would a weekend warrior who is yet to add structure and periodisation to their training.

Aero gains are up for grabs for everyone.

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Simplistically speaking aero gains should net you more because the speed and aerodynamic drag is a non-linear relation

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Yeah true but, to the OP’s question…should a dude sitting upright buy aero anything? Me: hell yes! Most people: hell no. Why is that? Aero may make more of an absolute difference at 34mph but no one here can sustain that for more than a couple seconds so no one here is worthy? BS. Everyone is deserving of aero everything. The guy riding 100 miles in 8 hours vs a guy finishing in 4 hours who saves more watts of drag with those deep wheels? Rhetorical question btw…

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Bling aside, saving watts is good and it really becomes noticeable at speeds above 20mph.

Aero testing suggests that 45mm wheels might save you 6ish watts at 30 kmh over 28mm rims, or a bit over 3%.

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Of course, matching external rim width to tire size is important to realizing aero benefits.

Ah yes Hambini (and his new best friends at Flo). The Prime wheels seems amazing for the money if his testing protocol is accurate.

Maybe you should consider (another?) bike fit. I had similar issues 2 years ago and the bikefitter has put my saddle 2 cm towards the handlebar (4cm behind BB) and 1 cm higher and he lowered my handlebar.
All tension dissapeared (neck, back and posterior chain) and I have a more aerodynamic position. This is the position on my new bike. Before I had an endurance position.

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I just want to say that as a fellow Domane owner looking at wheels I feel ya. I think I’m set on the Aeolus 3 Pro wheel. It’s 36mm deep, so the aero benefits are marginal compared to deeper wheels. But man I really love the looks of the 50mm deep wheels.

I’m justifying the upgrade because the stock wheels are heavy at 2200g. I also want to be able to use these wheels on future bikes, so the 36mm depth is nice for all around riding.

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Hambini is not a trustworthy source.

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@ErickVH

I am aware of some controversy regarding Hambini’s testing protocol, and how it differs from some of those used to date in the industry. And also how he seems to proceed fairly quickly to some pretty juvenile name calling in internet discussions.

However, I have not heard of anyone suggesting he is falsifying his data?

In any event, my takeaway from the data is generally how little difference there is between wheels of the same depth class, but that there is clear general trend to improved aero performance as rim depth increases. Are your conclusions any different from this?

The Bontrager guys were politiely saying that doesn’t match with our data. Zero Friction dismantled his bearing video. Hambini is not a valid source.

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Hi @Captain_Doughnutman - may I ask what type of wheels you picked up and where you got them? I would love to get a set of affordable aero wheels and was wondering about a good source for them in Canada. I have a limited budget for bike upgrades as I want to upgrade my mountain bike next and need to save funds for that.

The other challenge is that I would rather upgrade my road bike to one with disc brakes. Thus, getting new aero wheels for rim brakes wouldn’t be compatible with a newer road bike with disc. And a new road bike would come after a MTB bike and a gravel bike…

I think the most interesting thing about Hambini’s data is that he is testing as speeds more suited to amateur cyclists. The wheel companies have an interest in claiming their protocols are best for marketing reasons and as far as I can gather, Hambini has a bit of an ego problem (to put it mildly) and his interest is debunking. As ever, the truth on aero claims probably lie somewhere in between. But we must remember the main point of my post: aero wheels look cool. And looking cool makes you faster. Fact :wink:

Aerodynamic bike ( frame+wheel+handle bar) save you 1.5% on your speed. Therefore every minute you ride you save 1 second. If you can’t close a gap in 60 second you won’t close it with this extra 1 second. Keep training:)

Except a heavy shallow rim will have a much higher inertia than a lighter deep rim so it may spin longer, even with a slightly slower hub.

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