TOUR MAG AERO TEST 2016

[Zigmeister]

Is it 1-2% with a person on the bike, or just the bike...if just the bike, it is meaningless. I can assure you I know local pros, ride regular so-called "traditional" bikes, not even aero except maybe the wheels, and they can just ride everybody off their wheel...so with a 30% draft advantage on a complete aero bike setup, you get ridden off their wheel and down the road they go as everybody implodes.

Nothing to do with the bike, the person, V02 Max, lactic threshold etc..is just so superior, they can be riding any basic descent bike, and you are done for.

And eve with somebody at these guys levels, it really is meaningless mostly. How often does a breakaway actaully succeed, amateur/pros? Rarely, so ride all the aero crap you want, if you don't have the fitness/talent, doesn't matter what you are riding, won't make any difference.

80% of drag is the person on the bike, so you have to deal with that huge number first, then the bike/frame makes for so little, rolling resistance has as much/more of a difference than aero frames.

[KWalker]

True, but the point is assuming that the rider is equal to themselves and would ride with the same contact points, tires, and rims with the only dependent variable being the frame.

[53x12]

Are you sure the difference is "significant"? The difference between the fastest and slowest bike in that test is <1%, and about 2% compared to the round tube bike. What is the margin of error in these tests? It's not stated but I would guess that it is higher than 1-2% which would make the differences between these bikes statistically insignificant.

The difference between a fast vs. slow aero bike is around 20 watts which is closer to 10%. Not 1-2%. For a top end aero road bike to a traditional road tube road bike, the difference could be anywhere from 15-25% depending on make and model.

The good wind tunnels are <1% margin of error. By good I mean the San Diego Low Speed Wind Tunnel, A2 Wind Tunnel in North Carolina, University of Washington's F. K. Kirsten Wind Tunnel...etc.

Remember that proper design setup is important in limiting margin of errors. So being careful with how everything is setup and the parameters one is testing at.

Andrew Coggan Ph.D. even showed that you can create a very sensitive and accurate (low margin of error) wind tunnel in your own home with proper design and dedication to details: http://www.tririg.com/docs/CogganLSWT.pdf

So no, worry about "margin of error" is not a reason to say there is no difference between an aero road bike and a non-aero road bike.

[53x12]

Is it 1-2% with a person on the bike, or just the bike...if just the bike, it is meaningless. I can assure you I know local pros, ride regular so-called "traditional" bikes, not even aero except maybe the wheels, and they can just ride everybody off their wheel...so with a 30% draft advantage on a complete aero bike setup, you get ridden off their wheel and down the road they go as everybody implodes.

Nothing to do with the bike, the person, V02 Max, lactic threshold etc..is just so superior, they can be riding any basic descent bike, and you are done for.

And eve with somebody at these guys levels, it really is meaningless mostly. How often does a breakaway actaully succeed, amateur/pros? Rarely, so ride all the aero crap you want, if you don't have the fitness/talent, doesn't matter what you are riding, won't make any difference.

80% of drag is the person on the bike, so you have to deal with that huge number first, then the bike/frame makes for so little, rolling resistance has as much/more of a difference than aero frames.

Again, it is not a 1-2% difference. Why are you guys keeping stating that. The data is on the first page of this thread. The difference between the top aero road bike tested (Madone and Venge ViAS) and the worse in the group was just under 10%.




Again all of these straw man arguments need to die. This is not about person A on an aero road bike that is out of shape, on a 20kg bike, riding in an upright position on a day where the conditions are different than person B on a traditional road bike, that is in shape and putting out + 6w/kg on a 5kg bike and riding in an aero position.

This is about person A on an aero road bike vs. person A on a traditional road bike. The only difference is the frame. We aren't talking about conditioning level. We aren't talking about riding in the peloton. We aren't talking about anything else except the frame being the only variable that changes.

So take yourself and all that you represent as a cyclist. Put yourself on the fastest aero road bike (Madone 9, S5, AR, Venge ViAS) and compare yourself against yourself on a traditional road bike frame and you yourself will be faster on the aero road bike than yourself on the traditional road bike for that particular ride. Think of it as you vs you as a ghost rider riding the other bike right next to you.

[bm0p700f]

My argument is how much difference this actually makes in a race though I do race and train alot for racing well I have been this year. I have bought the Look and will be racing it on the 13th March hopefully if the bars arrive in time. I know coming from my current race bike (an round tubed steel bike) the Look is an a different league (i.e quicker) but what I am wondering is if I had the Trek would I actually be any quicker in the real world over riding the look. This is where testing falls down a bit. It gives some data in idealised conditions I don't ride in a wind tunnel though.

To use the example of cars. My 1989 BMW 530i has hopeless fuel ecomony. a modern BMW 530i is much better. In the lab though the same car is meant to do much more but it does not. So I just wonder how these lab aero tests translate in the real world. I know physics and this is what makes me question the data I see. I question all data it is the proper thing to do.

[53x12]

but what I am wondering is if I had the Trek would I actually be any quicker in the real world over riding the look. This is where testing falls down a bit. It gives some data in idealised conditions I don't ride in a wind tunnel though.

Yes you would be quicker with the Trek. The Tour test gave a difference of about 8w per their testing design and protocol. Even if riding in the peloton, that would still represent 5-6w increase bike over bike.

https://www.cervelo.com/en/engineering- ... he-peloton

Only you can answer if you would like an extra 5-6w while riding in the peloton or ~8w when you go on the attack or go for a sprint.

This is where testing falls down a bit. It gives some data in idealised conditions I don't ride in a wind tunnel though.

You don't need to ride in a wind tunnel though to get a real world representation of what will happen in the real world. Yes you won't ride at 0 yaw or ride at 15 yaw the whole day. So there comes some degree of projecting what the typical yaw a rider will face. Different camps on this idea, but most commonly held view is that it is the lower yaw (under 7-8 degrees) that are the most common for a rider.

Regardless, get a power meter and field test yourself. This idea of aero road frames isn't some voodoo science that can't be replicated and verified by the average cyclist that actually cares to verify it from themselves. Plenty of members on WW and other cycling forums field test with a power meter themselves. Do it yourself between your new Look and your old frame.

[AJS914]

Again, it is not a 1-2% difference. Why are you guys keeping stating that. The data is on the first page of this thread. The difference between the top aero road bike tested (Madone and Venge ViAS) and the worse in the group was just under 10%.

When I look at the first page of data and look at the times (3h22m for the fastest bike and 3h25 for the round tube) bike, I see a 1.5% difference in the time. I'm not seeing how you save a net 15-20 watts. Or maybe those watts don't translate to the times?

On average I'm riding 1.5 to 2 hours at a time so I see saving 1-1.5 minutes per ride to be a minuscule amount of time compared to the cost of a $10,000 bike. Similarly, The Zipp 404 wheels saved about a minute over the 3.5hr ride. Is that worth $2,000 for a wheelset?

Now if you are sprinting at the end of a race and a full aero bike gives you an extra bike length, I can see the benefit between losing and winning. Still is it worth a $10,000 outlay for an amateur masters level racer? I guess it depends on your level of disposable income.

[53x12]

When I look at the first page of data and look at the times (3h22m for the fastest bike and 3h25 for the round tube) bike, I see a 1.5% difference in the time. I'm not seeing how you save a net 15-20 watts. Or maybe those watts don't translate to the times?

For example, Trek Madone @ 204 watts vs. Storck Aerfast @ 222 watts. 18 watt difference. 18w/204w x100% = Storck being 9% slower than the Trek.

The times in the first chart take into other factors besides the CdA of the frames. The difference in CdA (as presented by watts by Tour Magazine) is the Trek being 18 watts faster (9%) over the Storck Aerfast @ 222 watts.

On average I'm riding 1.5 to 2 hours at a time so I see saving 1-1.5 minutes per ride to be a minuscule amount of time compared to the cost of a $10,000 bike. Similarly, The Zipp 404 wheels saved about a minute over the 3.5hr ride. Is that worth $2,000 for a wheelset?

Please don't act like people don't spend $10,000 on non-aero bikes. They do. Every price point that you show a traditional high end road frame, there is an equal price for a high end aero road bike. You want the high end Crumpton, Pinarello, Colnago at ~$4500-5000 for a frameset? Well you can get your Felt AR, Cervelo S5, Trek Madone...etc. at that price point.

Want to spend less on a frameset, there are those as well.

Now if you are sprinting at the end of a race and a full aero bike gives you an extra bike length, I can see the benefit between losing and winning. Still is it worth a $10,000 outlay for an amateur masters level racer? I guess it depends on your level of disposable income.

Is it worth paying more than a $100 for a bike by an amateur racer or your weekend cafe road cyclist?

[53x12]

Also of note, the difference of ~4 minutes between the Trek Madone vs. traditional frame with round tubing is massive. That is nothing other than the frame being different. That is a difference of ~1.2 miles. The Trek Madone rider (with same power output, same course...etc.) would have completed the race and the traditional frame rider would still be +1 mile behind. All from just the difference in frame selection.

[Krackor]

edit: math is off. Power is roughly proportional to velocity cubed, so a 1% power savings results in (1-.01)^(-1/3) = 1.003 times faster, or a 0.3% improvement in speed. 9% power savings is still enough for 3% speed increase. Plenty big enough to regularly make a difference in sprint finishes.

A 1% difference is worth quite a bit. Consider a 100m sprint - a 1% difference is 1 meter at the finish line. Pay attention to the world tour sprints this season and take note of all of the finishes that are decided by less than 1 meter. Also take note of how many of the sprinters are not riding aero framesets.

1% is big, but the test in this thread shows up to 9% difference among different aero frames. That's worth four and a half bike lengths in a 100m sprint! When a professional sprint is won by that distance it looks like a laughable blowout.

All that's not to mention the energy saved in the hours leading up to the race finish.

It may not be the most valuable equipment change, and it won't always make enough difference to win your race for you. But why wouldn't you take that advantage when it's available? It'd be like Boonen switching back to Ambrosio wheels for PR or Kittel using Ksyriums on the Champs Elysees. What a waste!

[SLCBrandon]

3 mins saved over a 3.5hr race isn't a big deal? I'm on the wrong forum.....

[Kayrehn]

I'll be happy to see this thread go back to discussing which aero bike rather than why aero bike...

Sent from my SM-G900F using Tapatalk

[Dez33]

Is it 1-2% with a person on the bike, or just the bike...if just the bike, it is meaningless. I can assure you I know local pros, ride regular so-called "traditional" bikes, not even aero except maybe the wheels, and they can just ride everybody off their wheel...so with a 30% draft advantage on a complete aero bike setup, you get ridden off their wheel and down the road they go as everybody implodes.

Nothing to do with the bike, the person, V02 Max, lactic threshold etc..is just so superior, they can be riding any basic descent bike, and you are done for.

And eve with somebody at these guys levels, it really is meaningless mostly. How often does a breakaway actaully succeed, amateur/pros? Rarely, so ride all the aero crap you want, if you don't have the fitness/talent, doesn't matter what you are riding, won't make any difference.

80% of drag is the person on the bike, so you have to deal with that huge number first, then the bike/frame makes for so little, rolling resistance has as much/more of a difference than aero frames.

Again, it is not a 1-2% difference. Why are you guys keeping stating that. The data is on the first page of this thread. The difference between the top aero road bike tested (Madone and Venge ViAS) and the worse in the group was just under 10%.




Again all of these straw man arguments need to die. This is not about person A on an aero road bike that is out of shape, on a 20kg bike, riding in an upright position on a day where the conditions are different than person B on a traditional road bike, that is in shape and putting out + 6w/kg on a 5kg bike and riding in an aero position.

This is about person A on an aero road bike vs. person A on a traditional road bike. The only difference is the frame. We aren't talking about conditioning level. We aren't talking about riding in the peloton. We aren't talking about anything else except the frame being the only variable that changes.

So take yourself and all that you represent as a cyclist. Put yourself on the fastest aero road bike (Madone 9, S5, AR, Venge ViAS) and compare yourself against yourself on a traditional road bike frame and you yourself will be faster on the aero road bike than yourself on the traditional road bike for that particular ride. Think of it as you vs you as a ghost rider riding the other bike right next to you.

Re bold: The argument should only be about the frame but you are quoting watts difference where the worst bikes had not very aero wheels. When the 100km test was done with control wheels the gap came back significantly. Therefore the gap was a lot lower than what you are quoting.

Also, keep in mind the watt savings table was done at 45kph. Not many riders can average that on a 100km ride. Bring the speed down to 35kph and you will probably see frame only account for 1% if you were lucky. There was a paper done years ago on the aero split between rider and bike. Rider takes 70-80% depending on position. Of the remaining wheels account for 1/3, then handlebars, then forks, frame a distant last. Will try and dig it out tomorrow.

Basically get your body in shape, buy some 404's and a Canyon integrated bar and don't worry about the rest.

[KWalker]

3 mins saved over a 3.5hr race isn't a big deal? I'm on the wrong forum.....

I think the argument here is that almost no one, especially an amateur, will ever be solo for that long. Hell most road races in the U.S. are barely 3hrs. I'd wager the longest most would ever see alone in the wind on this bike might be 10 minutes or less unless they were TT'ing.

But that's not really the point. As others have pointed out it comes down to Rider 1 choosing between Bike A and Bike B. One bike has one advantage, perhaps another a different advantage. The purpose of these tests is to provide accurate enough data to know what the advantages and trade-offs are.

For me I have to ride Specialized. I was comparing a ViAS to an older Venge and a Tarmac. I went with the Tarmac because the way my bike is built up it weighs 3lbs less. Comparing the modeling Tour did with my local race courses that 3lbs is going to make more of a difference at crunch time in a hard race than the ViAS aero for me at least. Plus my local rides involve a ton of climbing, descending, pad replacement, etc. so I'd only choose the ViAS if the difference was really substantial. Doesn't mean it isn't significantly more aero and faster on certain courses. Or that its a bad bike.

[53x12]

Re bold: The argument should only be about the frame but you are quoting watts difference where the worst bikes had not very aero wheels. When the 100km test was done with control wheels the gap came back significantly. Therefore the gap was a lot lower than what you are quoting.

Also, keep in mind the watt savings table was done at 45kph. Not many riders can average that on a 100km ride. Bring the speed down to 35kph and you will probably see frame only account for 1% if you were lucky. There was a paper done years ago on the aero split between rider and bike. Rider takes 70-80% depending on position. Of the remaining wheels account for 1/3, then handlebars, then forks, frame a distant last. Will try and dig it out tomorrow.

Basically get your body in shape, buy some 404's and a Canyon integrated bar and don't worry about the rest.

Round tube frame 3:25:16
Trek 3:21:55

3:21 (201 seconds) difference for the 100km ride between the Trek and the frame with round tubing. A rule of thumb for aero is that 50 g of drag = 0.5 s/km = 5 W = 0.005 m^2 CdA.

201 seconds /100km = 2.01 s/km = ~20 w.


45 km for the wind tunnel test (or 30 mph like many USA companies do) doesn't matter. They test at that level as it provides better data. The data is still valid for the real world. Actually, a slower ride (at a slower average speed) will save more time on the race than the faster rider. But this has been discussed multiple times on WW so no need to discuss that again. You can read several articles on that online if you are interested in that tidbit.

You sound like another guy that doesn't own a power meter? If I am wrong, sorry for jumping to that conclusion. But you sound like someone that doesn't do his own field testing with a power meter. There is plenty of time and watts to be saved by jumping ship from an un-aerodyanmic round road frame and riding a aero road frame. Only the rider can decide if that is worth it to them.