Is an aero frame beneficial? (light or aero bike faster?)

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Tinea Pedis
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by Tinea Pedis

airwise wrote:the point is there usually will be something to hinder you. Lack of comfort.

Subjective.


airwise wrote:Extra weight.

As long as it can be built to 6.8kg (not that all the Pro's bikes are this weight anyway, especially those going for an aero frame) then frame weight is not a factor.

And the Foil is no beef cake at any rate.


airwise wrote:Aero seems to demand compromises in all of these.

Yet to hear any complaints about aero frames being noodles. Again, to use the Foil as an example, said to be very 'direct'.


I don't have an aero frame and not planning on purchasing a new road bike any time in the future, so no vested interest. But even if I did have, the counter points just don't stack up.

To me at least.

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ras11
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by ras11

VNTech wrote:Do you all believe aero wheels provide an advantage, despite the fact that the data that prove their advantage comes from testing performed without all these other variables you think somehow remove aerodynamic advantage?

In fact, wheels are generally tested even more poorly, as they are rarely tested IN a frame and fork, making the tests absolutely nothing like the real world. And yet, the advantage of aero wheels is rarely argued against.

We tested aero wheels in a bike, and saw excellent gains. We tested aero road frames, and saw smaller but still excellent gains. Somebody please explain to me why these two results are being treated differently.


VNTech wrote:Do you all believe aero wheels provide an advantage, despite the fact that the data that prove their advantage comes from testing performed without all these other variables you think somehow remove aerodynamic advantage?...... Somebody please explain to me why these two results are being treated differently.


I think you are inferring more of an issue then there is. One or two folks posting about not trusting wind tunnels is not a trend or majority. This is a tangent argument that is sensationalizing the issue of aero road frames. I think most folks believe that aero frames work... it's just clouded in hype (in my opinion).

I agree that wheel aerodynamics and frame aerodynamics should be treated similarly. I involked the same argument in my earlier post, but for a different conclusion. That is, the windtunnel testing for road races should overlay with a higher yaw angle distribution than for TT. Again, i.e. just like with deep wheels, a Zipp 1080 might not be the fastest wheel in the pack because of it's shallow stall angle. Therefore, yes, the wheel analogy is good, but inferring that maximally aero is always better is a bit misleading. I believe that aero frames are not a black and white issue as you may have inferred.

I'm not opposed to promoting this article, I think it'll be good to get feedback from a lot of smart forum members.
:-) Toys-R-Us

airwise
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by airwise

Tinea Pedis wrote:
airwise wrote:the point is there usually will be something to hinder you. Lack of comfort.

Subjective.


And the aero advantages are unproven in real world conditions using real riders in real races or real rides. And they can never be proven/disproven hence the magic from a marketing POV.


As long as it can be built to 6.8kg (not that all the Pro's bikes are this weight anyway, especially those going for an aero frame) then frame weight is not a factor.
And the Foil is no beef cake at any rate.


How many of those reading WW race in UCI events and if they do , why are they worried about shaving grams?



Yet to hear any complaints about aero frames being noodles. Again, to use the Foil as an example, said to be very 'direct'.


Read the Tour test and see the description of the handling compromises of the more aerodynamic offerings. All I am saying is that there is no evidence whatsoever that aero road race frames are an overall benefit despite what the trade would like us to believe. Put simply, if there really was a benefit of any great significance, do you not think that major GC contenders would be riding the things day in day out? If you offered them a pill that boosted power by 5% they would all take it. So why not some swoopy uberframeset?

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Tinea Pedis
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by Tinea Pedis

You're saying because the evidence isn't there the metric of measure for a frame being 'aero' is on the same level as the 'comfort rating' of a frame?

Furthermore, the frames that are designed and marketed to people who are looking for that little aero advantage are the same people who won't be racing UCI sanctioned races (which is every race I can enter, local or otherwise) and are riders (read: racers) who would further thumb their nose at the 6.8 rule?

Also had no idea we were only debating to the confines of this forum.


I'm out.


I've run out of will to carry on debating with you. You've beaten me with experience.

Courant
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by Courant

ras11 wrote:That is, the windtunnel testing for road races should overlay with a higher yaw angle distribution than for TT. Again, i.e. just like with deep wheels, a Zipp 1080 might not be the fastest wheel in the pack because of it's shallow stall angle. Therefore, yes, the wheel analogy is good, but inferring that maximally aero is always better is a bit misleading. I believe that aero frames are not a black and white issue as you may have inferred.

I'm not opposed to promoting this article, I think it'll be good to get feedback from a lot of smart forum members.



ras11. Thinking about this yaw angle thing, actually I think it is probably the other way round... First, 25% drag saving at 40kph is about 10% velocity difference, so you can overlay that onto your yaw angles. But, critically, if you're properly drafting, you'll be to the side of the guy in front, so the cross wind component is also influenced by the lead rider. Because riders are more bluff side-on, the net effect should be to *reduce* the yaw angle of the drafting rider. This is also consistent with the lowest drag angle of e.g. aero wheels, which is something like 5-10 degrees, i.e. non-zero - in other words the flow is bending round the rider, producing a side force and a small negative drag contribution (thinking about streamline curvature), to have the effect of straightening the flow on the drafting rider.

Zigmeister
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by Zigmeister

All things being equal, the aero frame is faster/less drag/wattage. It is that simple. So the same rider if he was on another frame, who cares what the conditions, will be faster,, or in other described terms, drags in grams, which I like to translate into wattage output required. So, less wattage to maintain the same speed as previously over another frame/design. That translates to speed and better endurance with less physical fatigue over same distance. 20% of the total drag is the wheels/frames/bike itself. 80% is the rider.

So working on an aero position/riding position to a point is a good portion. After that, and again, all things being equal, the aero frame/wheels are faster for the same rider. That is why they ride them. they like how they are designed/handle/perform.

Lastly, top sprinters in the World are riding several well known "aero" frames. They don't seemed to be hinder or complain whatsoever about "stiffness". CDale Evo, Scott Foil, Canyon, Boardman AiR frame, Venge and the list goes on and on of guys riding all sorts of frames, many classified as newer aero setups, are sprinters on these bikes.

Cav of course rode the Venge until now his dogma...apparently that is stiff enough as well for him. Kristoff from Katusha who won the Stage 3 sprint of De Panne, seemed to hammer it just fine on his Canyon team Aeroad CF 9 team frame. That frame isn't even known to be that "stiff" compared to others.
Last edited by Zigmeister on Fri Mar 30, 2012 5:09 pm, edited 1 time in total.

VNTech
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by VNTech

ras11 wrote:I think you are inferring more of an issue then there is. One or two folks posting about not trusting wind tunnels is not a trend or majority. This is a tangent argument that is sensationalizing the issue of aero road frames. I think most folks believe that aero frames work... it's just clouded in hype (in my opinion).

I agree that wheel aerodynamics and frame aerodynamics should be treated similarly. I involked the same argument in my earlier post, but for a different conclusion. That is, the windtunnel testing for road races should overlay with a higher yaw angle distribution than for TT. Again, i.e. just like with deep wheels, a Zipp 1080 might not be the fastest wheel in the pack because of it's shallow stall angle. Therefore, yes, the wheel analogy is good, but inferring that maximally aero is always better is a bit misleading. I believe that aero frames are not a black and white issue as you may have inferred.

I'm not opposed to promoting this article, I think it'll be good to get feedback from a lot of smart forum members.


I don't think the issue is black and white either. I was merely pointing out the odd disparity between the general agreement that aero wheels are worth running, while aero frames are not. That makes no sense to me. In a race situation, I will take every advantage I can get. That means finding the optimum balance between aerodynamics, handling, and ride quality, since the latter two also can be considered "advantages." I think that with the latest batch of aero road frames, we have reached a tipping point where the drawbacks in ride quality and handling are small enough so as to be easily outweighed by the improved aerodynamics. Before, there was compromise. Now, there really isn't. So why not go aero?

(by the way, my original intention was not to promote the magazine, just to provide a little data for you all.)
VeloNews Magazine/VeloNews.com tech

airwise
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by airwise

Tinea Pedis wrote:I've run out of will to carry on debating with you. You've beaten me with experience.


I've tired of "debating" when questions are answered with questions so I'm out too. Forgot how futile forum "debates" could be. Sorry.

Zigmeister
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by Zigmeister

VNTech wrote:
ras11 wrote:I think you are inferring more of an issue then there is. One or two folks posting about not trusting wind tunnels is not a trend or majority. This is a tangent argument that is sensationalizing the issue of aero road frames. I think most folks believe that aero frames work... it's just clouded in hype (in my opinion).

I agree that wheel aerodynamics and frame aerodynamics should be treated similarly. I involked the same argument in my earlier post, but for a different conclusion. That is, the windtunnel testing for road races should overlay with a higher yaw angle distribution than for TT. Again, i.e. just like with deep wheels, a Zipp 1080 might not be the fastest wheel in the pack because of it's shallow stall angle. Therefore, yes, the wheel analogy is good, but inferring that maximally aero is always better is a bit misleading. I believe that aero frames are not a black and white issue as you may have inferred.

I'm not opposed to promoting this article, I think it'll be good to get feedback from a lot of smart forum members.


I don't think the issue is black and white either. I was merely pointing out the odd disparity between the general agreement that aero wheels are worth running, while aero frames are not. That makes no sense to me. In a race situation, I will take every advantage I can get. That means finding the optimum balance between aerodynamics, handling, and ride quality, since the latter two also can be considered "advantages." I think that with the latest batch of aero road frames, we have reached a tipping point where the drawbacks in ride quality and handling are small enough so as to be easily outweighed by the improved aerodynamics. Before, there was compromise. Now, there really isn't. So why not go aero?

(by the way, my original intention was not to promote the magazine, just to provide a little data for you all.)


I agree with the above.

As I stated earlier, all things being constant, with an aero bike and aero wheels, you will be faster than if you were on your "other" CDale fat tubed bike, or whatever inferior frame/wheel design. Who cares what the actual conditions are, you are comparing the frames in a very specific controlled environment, which makes the test completely valid.

That is why I said, all things being equal, if you were to be racing on an aero frame, then in the middle of pedaling the bike, switch to a non-aero frame with chunky wheels, you will be slower, or in other words, have more grams of drag, or required more wattage to overcome said drag to maintain the same speed as the aero setup.

I personally want any advantage I can get that will save wattage. That is why I run an aero frame and zipp 303 FC wheels. It is "faster" than my old deep 50mm carbon setup and CDale SuperSiz fat tubed frame, that is for sure.

cep111
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by cep111

I have both bikes used in the Tour review, a fat tubed Cdale and a 2010 Talon. I'm a huge Cdale fan, love the caads. The Talon feels very comfortable on the road, the ride is fine. I do here some chain rub when under a heavy push so I think the narrow frame may have some flex but it seems to climb well anyway. If I was going to do a TT I would take the Talon anyday. If I'm out for a fun lively group ride I'm all over the Caad.

Supposedly the new EVO frame is a bit of both worlds. Maybe I should sell everything off and buy 1 EVO

spartan
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by spartan

roadbike.de did a comparison test of the top 8 new road carbon frames.

evo was rated top bike. it won over sworks sl4, scot foil, giant advanced sl, cervelo r5 vwd, bh ultralight.

http://www.roadbike.de/test/bikes/im-ro ... 5636.9.htm
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ex 2019 S-works SL6
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ex 2016 Giant TCRAdvanced Sl
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mjduct
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by mjduct

Courant wrote:airwise,

By the figures above, aero wheels are worth something like Cd=0.05, frame about Cd=0.03. These are relatively big numbers! To put this in context, assume two riders hit the front of the bunch at 40pkh. Rider A has a Cd=0.8, rider B has Cd=0.79 (a 1-point change, i.e. much smaller than the above numbers). Both start to put out 800W and hold it. The difference between rider A and rider B is something like 10cm after 100m. The difference grows over the next 100m because aero power goes with v^3. That 10cms is clearly a race-winning difference, all else being equal. The faster you go, the bigger the margin; the further you go, the bigger the margin. I'd take that advantage, thank you very much!



In which case after rider B gets a half meter ahead, Rider A gets in his slipstream and Milks him until the last 100 Meters of the race. Where the energy saved by churning out only 600W to the front mans 800W for any amount of time will be spent in a sprint and savored in victory...

See 2012 Milan San Remo, Simon Gerrans, Fabian Cancellara

cep111
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by cep111

spartan wrote:roadbike.de did a comparison test of the top 8 new road carbon frames.

evo was rated top bike. it won over sworks sl4, scot foil, giant advanced sl, cervelo r5 vwd, bh ultralight.

http://www.roadbike.de/test/bikes/im-ro ... 5636.9.htm" onclick="window.open(this.href);return false;


The other German mag "Tour" gave the Evo, frame of the year too.

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prendrefeu
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by prendrefeu

mjduct wrote:
Courant wrote:airwise,

By the figures above, aero wheels are worth something like Cd=0.05, frame about Cd=0.03. These are relatively big numbers! To put this in context, assume two riders hit the front of the bunch at 40pkh. Rider A has a Cd=0.8, rider B has Cd=0.79 (a 1-point change, i.e. much smaller than the above numbers). Both start to put out 800W and hold it. The difference between rider A and rider B is something like 10cm after 100m. The difference grows over the next 100m because aero power goes with v^3. That 10cms is clearly a race-winning difference, all else being equal. The faster you go, the bigger the margin; the further you go, the bigger the margin. I'd take that advantage, thank you very much!



In which case after rider B gets a half meter ahead, Rider A gets in his slipstream and Milks him until the last 100 Meters of the race. Where the energy saved by churning out only 600W to the front mans 800W for any amount of time will be spent in a sprint and savored in victory...

See 2012 Milan San Remo, Simon Gerrans, Fabian Cancellara


Fitness, Tactics, many other variables > Aero.
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JkAlentejano
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by JkAlentejano

I really think that in some years everybody will be laughing about the tests from today...
My opinion is that the aero stuff does have some beneficts depending on the situation, but they are a marketing product not a true engineered one, simply the tests aren´t good for real world advantages assurements, so the brands "cheat" a little in the tests and send them to the marketing department to make big sells.
Some time ago someone developed a device do recorde winds and stuff while riding in the real world, and are testing it, for me it will set the new standart for testing, but it's not perfect either because the box siting under the handlebar it´s not the same as not being there...nevetheless much better than wind testing, and when the market start make real tests and data the first thing they will say is this tests right now are all trash, as the products and obviusly the new product it is the real thing, as they always do, just the diference is that time it will be truth.

just some of my cents...

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