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

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VNTech
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by VNTech

Apologies for continuing this, but some of the posts here are quite uninformed. To set the record straight, here are some numbers from our own testing, and I'll even relate it to pro cycling! Data are from our third-party testing, nothing from manufacturers, you'll see the figures pop up in the magazine over the next few months. The new test on aero road bikes should hit newsstands in a few days, for those interested. And before you ask, no I will not provide any additional data :)

Fact #1: On Boonen's Venge, swapping from 32-spoke wheels to the fastest wheels in our test will save ~225 grams of drag (using weighted average across -20 to 20˚ yaw, at 30mph).

Fact #2: With those same fast wheels, swapping from a steel round-tube frame to a Venge will save 141g of drag.

Conclusion: If you say wheels make a difference, but somehow the frame does not, you are mad.

Specialized and the rest of Boonen's sponsors have done a bunch of education with the man himself year. In the past, he has always run traditional classics wheels in Flanders/Roubaix. This year, you will see that he does not. He has "bought in" to the aero advantage.
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HammerTime2
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by HammerTime2

VNTech wrote:Fact #2: With those same fast wheels, swapping from a steel round-tube frame to a Venge will save 141g of drag.
What diameter round tubes is this for?

VNTech
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by VNTech

HammerTime2 wrote:What is "standard", since tube diameters have gotten bigger over the years, but I believe classic 28.6 mm are still being made in addition to larger diameter? Based on your writing that standard round-tubed steel frame is likely quicker than most non-aero carbon frames, I'm guessing you mean 28.6, is that correct?


You are correct.
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headwind816
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by headwind816

hansonator69 wrote:
How often does a frame hit clean air in a road race? (i.e. air that isn't churned up by riders around them) Unless you are always on a solo breakaway, the advantages are negligible.

Second time today I read about unclean/dirty air, but the first time had to do with tire width. How many pros, if any, run a wider tire in back?

I wonder if Oakley partakes in wind tunnel testing?

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prendrefeu
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by prendrefeu

Although I did state that aero frames make some difference only very far down the list of factors that determine the outcome of a race, after reading Caley's post I'm now Google-searching permanent body modification to make sure my body is aero.

Afterall, the human body is the largest portion of a 'racer' on a 'racing bike' during a race, has the largest surface area no matter which way the wind is blowing, and is the biggest factor to 'aero' by far. So... therefore, I'm thinking I'll get make myself 'aero' before certain bicycle brands start marketing their 'aero' body modifications and charge a premium for it since their brand will be attached to it.

Stiffness? We've already got pills for that, son.

I guess stiffness and aero are all that matter these days? :noidea:

And I guess we ignore the fact that even in a TT a non-aero frame build did not prevent the rider from winning against other riders on their aero-frame builds in a recent race in Colorado. *cough*

Does aero matter? Sure. Not so much in a RR, more so in a TT. Where it's one person against the clock. Even then, is it a guarantee? Nope.
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carbon2329
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by carbon2329

VNTech wrote:Apologies for continuing this, but some of the posts here are quite uninformed. To set the record straight, here are some numbers from our own testing, and I'll even relate it to pro cycling! Data are from our third-party testing, nothing from manufacturers, you'll see the figures pop up in the magazine over the next few months. The new test on aero road bikes should hit newsstands in a few days, for those interested. And before you ask, no I will not provide any additional data :)

Fact #1: On Boonen's Venge, swapping from 32-spoke wheels to the fastest wheels in our test will save ~225 grams of drag (using weighted average across -20 to 20˚ yaw, at 30mph).

Fact #2: With those same fast wheels, swapping from a steel round-tube frame to a Venge will save 141g of drag.

Conclusion: If you say wheels make a difference, but somehow the frame does not, you are mad.

Specialized and the rest of Boonen's sponsors have done a bunch of education with the man himself year. In the past, he has always run traditional classics wheels in Flanders/Roubaix. This year, you will see that he does not. He has "bought in" to the aero advantage.



I hope this is not too OT but....
I am not Anti-Aero or Pro-Aero (I have both types of frames), but I have a few concerns:

I am in the medical field and
Rule #1 is: Don't belive research that is produced by the manufacture who is selling/making it.

It seems in the bike industry that is all we really get, (Adrian & Madcow from FWB are very valuable because of this=independant) so we are at a disadvantage (but VN can help with their reviews), but if there "research" about "Specialized" comes from Specialized then we are again at a disadvantage:
So.....
We get Aero charts from Zipp= wow Zipp, is fastest
We get Aero charts from Enve= Wow, Smart system is fastest
We get Aero frame info from "frame company" = Wow there frame is fastest (as "saves___ watts"
And there is no way to combine them because they do them differently.
(not to mention, most companies arent' testing the "whole system" with:
-cages,
-bottles,
-THE RIDER,
-peloton
-jersey,
-gilets,
-helmet,
nor are they able to facter in (very well, as a whole...and accuratly);
-changing wind conditions,
-riders changing directions,
-the dynamics of the pelaton or group brake-away,
-different wheelsets (with a given frame)
-for wheel-are they testing varied spoke counts
-are they specifying a specific tire used (and it's width. Maybe they are in this case)
-weather/humidity (yes, this has to do with the rider, but what/who wins races..it is a factor)
-varience in ability (yes, this has to do with the rider, but what/who wins races..it is a factor)
-varienece in heat (yes, this has to do with the rider, but what/who wins races..it is a factor)
etc...)
There are so many factors, it is unlikely we will ever know facts, we will really only know Aero will help in some small way (and that is great, but lets put it into perspective)

I, personally, don't believe much of it (thier research could be correct, for all I know), but that is how I was trained. If I submitted research like that I would be laughed at.

I could be wrong (I probably am :D ) but:
It seems like we are making "Mountains (minutes) out of Mole-hills (milliseconds)"
(and yes, milliseconds can make a difference in winning a race, but what percentage of cyclists are competing at that level = 1% or less ? )

But "in a nutshell", the above quote seems interesting, but have we ever recieved date from company "A" saying that anything they (company "A") produce, isn't "better", "faster" etc... that the rest (or the previous model).

As an example: have very many of us been to the LBS where we have been told that "A_____" is great and "B_____" is bad, and it is because "A" is what they are selling and "B" is what the LBS down the street is selling.

The odds of really knowing (I am not saying they lie, per-say) the truth, from Marketing, is pretty slim, you have to admit. You don't get you research form "the maker" of the product.

What is comes down to is:
Aero helps, I am sure...to what degree...we will (probably) never know.
So if you enjoy it and want to try anything to get an edge...great, go for it.
But if you don't belive it, there is some truth to that as well....great, too.


I just think we should see things for what they are (and if we don't know what they are they we should at least admit it)

Sorry if this is OT and too long :D
Last edited by carbon2329 on Thu Mar 29, 2012 9:59 pm, edited 5 times in total.

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TwiggyTN
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by TwiggyTN

hna wrote:I believe that, while aerodynamics are extremely important, an aero frame is much less important than wheels, skin suits and especially an aerodynamic position on the bike.


So true! Love all these guys I see in my races with all the trick Aero gear but have that "sit up and beg" position on the bike. You drag has way more to do with your body position at speed than anything else...:idea:

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Epic-o
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by Epic-o

prendrefeu wrote:And I guess we ignore the fact that even in a TT a non-aero frame build did not prevent the rider from winning against other riders on their aero-frame builds in a recent race in Colorado. *cough*


Maybe because the rider with the non-aero frame build was much stronger and he overcame the aerodynamic deficit?

:roll: :roll:

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prendrefeu
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by prendrefeu

Epic-o wrote:
prendrefeu wrote:And I guess we ignore the fact that even in a TT a non-aero frame build did not prevent the rider from winning against other riders on their aero-frame builds in a recent race in Colorado. *cough*


Maybe because the rider with the non-aero frame build was much stronger and he overcame the aerodynamic deficit?


It could be one of many factors. That's the point. Aero is not everything.
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Tinea Pedis
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by Tinea Pedis

It was asked to keep the PRO Cycling thread on topic, it was ignored.

So here's a thread to carry on the debate.

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Getter
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by Getter

For the clueless...what is the equivalent of 225gr of drag?

Is there some kind of example that the layman can relate to? :smartass:

...and so I take it Bonnen is using 303's this year?

thisisatest
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by thisisatest

when comparing an aero frame to a traditional frame, the whole point is the other factors are to remain constant. it is how things are tested-changing one variable at a time. so one frame vs another frame, with the same rider, one is faster. it has nothing to do with whether or not some dude next to you can beat you on inferior equipment.
yes, the tests dont account for varying environmental conditions, but they do test different, constant conditions. they do test with and without bottles, in different locations. they do test in different body positions (look up Dan Empfield (sp?)), and for the little things that havent actually been tested, such as what happens when there is a 30% chance of rain, with high humidity, the results can generally be extrapolated.
in groups, in dirty air, and especially when drafting immediately behind someone, the aero benefits still apply. sometimes to a lesser degree (possibly to a higher degree when following someone closely in a paceline, at some angle to the wind), but likely significant still.
and as far as different companies coming up with different results, yes, zipp says theyre faster than enve and vice versa, but neither says the other wheel is slow, EVERYONE agrees that ksyriums are slow. indeed both companies' wheels are close enough to each other to choose one for the other reasons (whether you like molded spoke holes or exposed nipples, zipp hubs or other hubs, spoke counts, how it matches your frame). similar results with aero testing, specialized vs cervelo vs whatever... their results are close enough that independent tests have different "winners" as well, but the top 3 are likely the same top 3, with close numbers, sometimes only varying on their philosophy, such as what yaw angle range is considered more important to them.
in the end, doubters will doubt.

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BeeSeeBee
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by BeeSeeBee

Getter wrote:For the clueless...what is the equivalent of 225gr of drag?

Is there some kind of example that the layman can relate to? :smartass:


The approximation some aerodynamically inclined posters at Slowtwitch give is: 0.1 lbs (50 g) of drag (at 30 mph) = 0.5 s/km = 5 W = 0.005 m^2 CdA = 0.0005 Crr

My only questions are if the upcoming test was done with a rider/dummy or if it was just stand alone bikes like in the past. Also, if they were tested with two bottles, though I suppose we'll have the answers in a few days.

airwise
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by airwise

VNTech wrote:Fact #1: On Boonen's Venge, swapping from 32-spoke wheels to the fastest wheels in our test will save ~225 grams of drag (using weighted average across -20 to 20˚ yaw, at 30mph).

Fact #2: With those same fast wheels, swapping from a steel round-tube frame to a Venge will save 141g of drag.

Conclusion: If you say wheels make a difference, but somehow the frame does not, you are mad.

Specialized and the rest of Boonen's sponsors have done a bunch of education with the man himself year. In the past, he has always run traditional classics wheels in Flanders/Roubaix. This year, you will see that he does not. He has "bought in" to the aero advantage.


Would that be why he ran the SL4 instead of the Venge to WIN Gent Wevelgem last week at an average speed of circa 30 mph? :wink:

justkeepedaling
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by justkeepedaling

One word for that, cobbles. The Venge is not the most comfy bike out there ;)

Velonews, have you tested a S5 in the tunnel? There is talk on slowtwitch that the S5 is faster than a Specialized Transition and that it fared better than a Cannondale Slice in a test

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