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Discussion Starter · #1 ·
Anyone know of any testing of aero frames in real world non-TT conditions? Like corrected for the same body positioning, with water bottles, normal wind yaw, etc.
 

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Discussion Starter · #3 ·

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Discussion Starter · #5 ·
You mean real world comparison like this?

Wind tunnel is fine with me, but I'd like to see it with normal setups on the bike. Like, with a cyclometer, water bottles, non skin suit, no TT helmet, etc. Just set up an Aero frame just like how it would normally be taken out on the road for an enthusiast, then do the exact same setup with a round tube bike with the same components. Make sure rider position is the same for both. Use realistic yaw angles and speed. I would imagine that a lot of the claimed aero advantage comes from rider position, and I would imagine things like water bottles would negate a lot of the frame advantage too.
 

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The problem is that frames don't mean squat.

You're not seeing anyone put out data that isolates the frame for a reason. Even Spec. flat out refused to release that information after they said they came here to do exactly that. Why? Because frames don't mean squat. Their new Venge frame is not that fast at all, no frame is super fast. It's how the cockpit is setup on the frame that makes more difference than the frame itself.

If you have an aero frame but have a stem that's anything above -17, meaning if the stem is not either perfectly horizontal or pointing down, you've wasted your money on the frame. There's a reason the new Venge mandates a -17 stem and puts riser handlebars and such to compensate. They have to have that in order to meet the claims about the bike.

Seriously. The frame means almost nothing. How comfortable you are on the frame will translate to more power and savings than how the tubes are shaped. I'm not talking your aero position, I'm talking straight comfort. Just being comfortable will net you more power and aero savings than a top of the line aero frame. The frames mean almost nothing in this game, less than is even worth talking about.
 

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Discussion Starter · #7 · (Edited)
The problem is that frames don't mean squat.

You're not seeing anyone put out data that isolates the frame for a reason. Even Spec. flat out refused to release that information after they said they came here to do exactly that. Why? Because frames don't mean squat. Their new Venge frame is not that fast at all, no frame is super fast. It's how the cockpit is setup on the frame that makes more difference than the frame itself.

If you have an aero frame but have a stem that's anything above -17, meaning if the stem is not either perfectly horizontal or pointing down, you've wasted your money on the frame. There's a reason the new Venge mandates a -17 stem and puts riser handlebars and such to compensate. They have to have that in order to meet the claims about the bike.

Seriously. The frame means almost nothing. How comfortable you are on the frame will translate to more power and savings than how the tubes are shaped. I'm not talking your aero position, I'm talking straight comfort. Just being comfortable will net you more power and aero savings than a top of the line aero frame. The frames mean almost nothing in this game, less than is even worth talking about.
My instinct would be to agree with this. I just want some data. I guess Aero wheels make more difference than you'd expect too though. But the wheels don't have as much interference like your legs, body, waterbottles, etc being in the way either. The only thing that makes sense to me is the narrower frontal area. If there is any difference, you'd think it is entirely mitigated by even the smallest difference in your day to day performance variation, slight changes in body position, or even just having 2 water bottles instead of 1.

Also worth noting is that independent tests have shown about 40g of drag difference between a round tube road bike and a TT bike. That data is a couple years old, but specialized and others would have you believe that there's now 200-300g drag difference. I doubt that there's more than a couple g drag difference between a new venge and a shiv from a couple years ago. On the other hand, different tires have more Aero difference than I'd expect too.
 

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If you are looking to be more aero during your weekend ride or commute, this may be more economical and effective than aero frame.
 

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A few months ago, I complied a bunch of data from my personal rides to compare the differences between the there bikes I've owned.

1. Specialized Tricross


2. Specialized Allez Comp


3. Specialized Venge Pro


The Strava segment that I used was a downhill segment that is .5 mile long and drops 7%. I chose this because I thought it offered a few advantages. First, its downhill and fairly steep, so I think it tends to eliminate variables in pedaling and strength. Its the type of hill that you come into with some speed and you simply tuck and fly down it. Second, I've done it a LOT.. 84 times over the course of the last 2.5 years and I've done it using each of the bikes. I've owned. I figured that using a segment with a larger sampling would also smooth out differences of variation.

As far as the bikes go, they were all set up readably similar.... all bikes had 2 bottle cages with a bottle and storage container. Both the Allez and Tricross were using 50mm aero wheels, while the Venge has 60mm wheels (although, some of the Venge results did come while I was running the 50's). For the most part, my fit has remained similar, but as you can see the stems on the Venge and Allez are slammed now, they haven't always been and in any case, with all 3 bikes, I'd drop down and tuck as closely to the top tubs as I could, so handlebar position and normal ride height shouldn't effect the numbers too much. In terms of tires... all of the Tricross times were done using GP4000s II's and all of the Venge and Allez times were done using S-Works Turbo tires.

here's the chart comparing time vs. speed



You can clearly see there are trends present... The Venge has the most samples and is represented across the whole spectrum, but its also clear that ONLY the Venge is present at the absolute fastest end of the spectrum. The Allez begins to show up a few mph slower and a few second slower and the Tricross again, a few mph slower and seconds slower. Is it possible to eliminate all variables and make the tests solely about the frames, no... but at the same time its real world and there's a clearly a difference. We're not talking about much in terms of time difference, but we're also only looking at a segment that's half a mile 4 seconds across a 40 second segment is a 10% difference. It's also clear that there are times for the Venge at the very slowest end of the chart, which are probably days that I was tired, or talking to a buddy or just not going for it as I started into the segment, so its pretty clear at that rider effort level is the biggest influence.... but at the same time, if you WANT to be at the fast end of the spectrum, it's clear that the aero set up gives you an advantage.
 

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The new Trek Madone white paper might be the closest to what you are looking for.
http://brimages.bikeboardmedia.netd...2015/06/TK15_Launch_Madone_Whitepaper_min.pdf

The Felt AR Wind Tunnel paper also has some good information.
http://aerogeeks.com/wp-content/upl...-ar-v-comp-aero-test-procedure-rev-b-1-ag.pdf

I disagree that the frame means nothing. Everything contributes to CdA and improvements to any part subtract from the total. Yes, the rider position and clothing is by far the biggest contributor but wheels make a difference and so does the frame.

Edit: I do agree that most likely variations in your form on a particular day will trump differences from aero wheels or an aero frame. But all else being equal you will be faster on the aero frame. It's definitely not cost effective to replace your frame with an aero one, but if you are already shopping for a new frame it would be foolish not to consider aero options.
 

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Discussion Starter · #11 ·
The new Trek Madone white paper might be the closest to what you are looking for.
http://brimages.bikeboardmedia.netd...2015/06/TK15_Launch_Madone_Whitepaper_min.pdf

The Felt AR Wind Tunnel paper also has some good information.
http://aerogeeks.com/wp-content/upl...-ar-v-comp-aero-test-procedure-rev-b-1-ag.pdf

I disagree that the frame means nothing. Everything contributes to CdA and improvements to any part subtract from the total. Yes, the rider position and clothing is by far the biggest contributor but wheels make a difference and so does the frame.

Edit: I do agree that most likely variations in your form on a particular day will trump differences from aero wheels or an aero frame. But all else being equal you will be faster on the aero frame. It's definitely not cost effective to replace your frame with an aero one, but if you are already shopping for a new frame it would be foolish not to consider aero options.
I just don't buy the manufacturer data for a second.
 

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I just don't buy the manufacturer data for a second.
Well in that case there isn't a whole lot of independent test data out there. The only one I am really aware of is the Tour test, which has it's own issues, see some discussion here: TOUR MAG AERO TEST 2016 - Weight Weenies. I think Velo Magazine did a test this year but I can't find the link right now.

For what it's worth at least in the two papers I linked the data lines up decently between the two wind tunnel tests.
 

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The problem is that frames don't mean squat.

You're not seeing anyone put out data that isolates the frame for a reason. Even Spec. flat out refused to release that information after they said they came here to do exactly that. Why? Because frames don't mean squat. Their new Venge frame is not that fast at all, no frame is super fast. It's how the cockpit is setup on the frame that makes more difference than the frame itself.

If you have an aero frame but have a stem that's anything above -17, meaning if the stem is not either perfectly horizontal or pointing down, you've wasted your money on the frame. There's a reason the new Venge mandates a -17 stem and puts riser handlebars and such to compensate. They have to have that in order to meet the claims about the bike.

Seriously. The frame means almost nothing. How comfortable you are on the frame will translate to more power and savings than how the tubes are shaped. I'm not talking your aero position, I'm talking straight comfort. Just being comfortable will net you more power and aero savings than a top of the line aero frame. The frames mean almost nothing in this game, less than is even worth talking about.
you've got a few false dichotomies there - the cockpit setup obviously contributes to the drag produced by a frame since it's a leading edge, but it doesn't mean the frame design doesn't affect overall drag. I don't think there's much dispute that a well-designed aero frame can save approx 60-120 seconds/40km over a standard round frame holding rider position and wheels constant. The upper figure would be for aero bars etc.

That might not sound like much, but it's more time savings that people are willing to pay thousand for in terms of a few hundred gram savings for ascent time savings in a lot of contexts.

It's also possible to get comfortable on an aero frame.
 

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Discussion Starter · #14 ·
you've got a few false dichotomies there - the cockpit setup obviously contributes to the drag produced by a frame since it's a leading edge, but it doesn't mean the frame design doesn't affect overall drag. I don't think there's much dispute that a well-designed aero frame can save approx 60-120 seconds/40km over a standard round frame holding rider position and wheels constant. The upper figure would be for aero bars etc.

That might not sound like much, but it's more time savings that people are willing to pay thousand for in terms of a few hundred gram savings for ascent time savings in a lot of contexts.

It's also possible to get comfortable on an aero frame.
I dispute that. As I pointed out before, the only independent test I've found on this indicated only a ~17 second savings. However, the study is several years old. Aero frame manufacturers would have you believe that even between 2 premium Aero frames, there could be 200g drag difference. This is just nonsense.
 

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I dispute that. As I pointed out before, the only independent test I've found on this indicated only a ~17 second savings. However, the study is several years old. Aero frame manufacturers would have you believe that even between 2 premium Aero frames, there could be 200g drag difference. This is just nonsense.
Link to the test? What about the tour test I linked?
 

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Discussion Starter · #16 · (Edited)
Can't find the study itself right now. It was VeloNews. Here were the results though. Buying Time: Which Aero Equipment Offers the Most Benefits? | ACTIVE.

I can't read the details of the tour mag test so I can't comment on it other than to say it appears their "round tube frame" numbers were pulled from thin air. They should compare actual round tube frame bikes to the aero frame bikes. A "round tube frame" could mean a commuter frame for all we know.
 

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Can't find the study itself right now. It was VeloNews. Here were the results though. Buying Time: Which Aero Equipment Offers the Most Benefits? | ACTIVE.

I can't read the details of the tour mag test so I can't comment on it other than to say it appears their "round tube frame" numbers were pulled from thin air. They should compare actual round tube frame bikes to the aero frame bikes. A "round tube frame" could mean a commuter frame for all we know.
I'm not sure what round tubed bike they used, but even between the aero bikes there was about 90 seconds from best to worst over 100k when using the same wheels.
 

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Discussion Starter · #19 ·
From stevesbike's link, Tom A (Blather 'bout Bikes) did a chung test on two cervelo tri frames: Something borrowed...something FAST!: Triathlon Forum: Slowtwitch Forums. He found about 2.5 seconds per kilometer difference between the two which be right in the middle of the 60-120 seconds over between two tri frames, now imagine the difference to a round tubed frame.
If those results were even remotely true, Specialized would be advertising 6-7 seconds gained per km.
 

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If those results were even remotely true, Specialized would be advertising 6-7 seconds gained per km.
I don't know what to tell you. You don't believe the manufacturer data. You don't believe the third party data except for one study that you can't find the details of because it supports your argument. If you're an aero flat earther just say it and I can check out of this thread.
 
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