New aero test: 12 aero frames vs 12 "unaero" light frames

[highdraw]

The error in your logic here is that you saw what bikes you were riding. You likely decided the ride quality would be dramatic before you ever clipped in. I'd lay a wager that the difference in ride quality could easily be offset/overcome by tire pressure.

And the error in your logic is the benefit of the aerodynamics of a Venge eclipse the performance advantage of a Tarmac. Tell that to the guy who won the TdF this year. He chose a Tarmac as did most of the riders in the peloton this year versus a much smaller percentage on a Venge. If there was no downside to the Venge and only an aerodynamic benefit, he would have been on one.
In engineering parlance this is referred to as no free lunch.

Can you point out where I said that? I offered no opinion on the topic of aero vs. comfort

Point is, with the undeniable benefit of aerodynamics of aero tube bikes versus fat tube bikes, why isn't everybody on an aero bike?
The answer is simple. Because the shape of tube sections is exactly the opposite (diametric) to best ratio of vertical compliance to lateral stiffness. So it isn't a question of, is an aerodynamic bike being more slippery, but rather what is the cost of being more slippery to overall riding characteristics. This is why most top riders in the pro peloton are on less slippery round tube bikes. The whole lame refrain of well, well, most of the time riders are in the peloton draft. Don't you when you race? If you don't, then I want to race against you. I want you to pull the whole race and then I will drop you like a bad habit in the sprint. Do you think the top riders in the world know how to race?....or even know to choose the best bike for themselves based upon their testing of riding a bike 6 hours a day? I laugh at all the guys who say their riding style doesn't apply to them. When is this? When you race against 10 other guys are your always pulling? If so, I want to race against you. How about racing up hills? Or over broken pavement? Who wins those races drafting or not. Or maybe you are racing to the grocery store on your aero road bike in your own air and you feel faster...lol.

[IchDien]

According to Cervelo you still benefit when drafting.

[highdraw]

Not to jump into your little love fest here, but many pros, ride what they are given. Since all but the UCI World teams, are poor and don't make much money. Most are flat broke and can keep/sell the equipment/bikes at the end of a season. So they are happy to have stuff paid for and for free. Beggars can't be choosers. Furthermore, if another human being can detect a mm or two of change to their seat height, just because they are pro, doesn't mean a high level, or even regular person doesn't feel/detect that as well. Pro mechanics get that type of feedback all the time. Making comments like, did you change my seat height? Til? Handlebar reach? After measuring multiple times....ooops, 2mm forward on the setback, or height was found.

You ever notice when a web page loads 160ms slower? That is about the threshold for people to detect something with the eye. And the brain will process that in a matter of 15-50ms.

With that said, to make any claim that you can't tell the ride qualities of a bike, is absurd. I personally went from a Scott Foil Team, one of the stiffest bikes made today in the HT and BB to a Foil 15, which is the HMF carbon layup, compared to the HMX of the team. The ride qualities were very easy to discern #1, and #2, as a 165-170lb sprinter, I can assure you, the flex of the HT and particularly the BB area on the Foil 15 was noticeable to me. At times, I'm still a bit unnerved by it in certain circumstances. One thing a sprinter doesn't like is any type of odd flexing going on while on the power in sketchy situations. In addition, I can easily tune the ride qualities with wheels/tubulars, stems/handlebar combos etc that have made the Scott Foil a very nice riding bike and tolerable even 60+ miles high intensity training over a variety of surfaces and terrain, flat/hills. Still it's ride, especially the HT/handlebar area, every pebble and pavement variation you feel right up into your hands. But I like that personally.

Now compare that to let's say a Cannondale Supersix, or EVO which I've owned both, those bikes ride like a luxury Rolls Royce. The Evo being stiff, but very well tuned to not pass that onto the seat/BB/HT area.

Lastly, the seat post things you guy talk about. Maybe you should relay over to Dave and Felt you have the 3T mounting mast/rubber vibration dampening technology option to limit and buffer the harshness of the BB and seat tube vibration. Apparently the seat post/seat tube does make a difference, and design of the aero tubes/shapes, that has been known and proven over and over compared to a round tube and physics.

To respond to your comment about riding what you are given is bogus when it comes to aero versus non aero frame discussion. Most of the top brands that supply to pro teams have both genres of bikes. Take Specialized in the pro peloton which are ubiquitous. Nibali and Contador were not told they had to ride a Tarmac versus Venge. They 'chose' to ride a Tarmac versus Venge.
They had a choice and chose the fat tube bike with better ride quality and power transmission.

[highdraw]

According to Cervelo you still benefit when drafting.

In the case of that argument then, all riders in the peloton should be on aero bikes and most aren't.

[IchDien]

http://www.cervelo.com/en/engineering/a ... loton.html

Asker Jeukendrup (High-Performance Cycling, 2002) measured a 30% decrease in power required while drafting, compared to riding alone. This roughly matches the drag savings we’ve measured on the road with our on-bike instrumentation. This decrease is due only to the reduction in aero drag when drafting, as nothing else changes: mechanical friction and rolling resistance are unaffected by drafting.

Most drag-yaw charts are taken from wind tunnel test data for a single bike, not drafting. This data is usually the source for the most commonly cited drag savings. So when you’re in a group, discount the drag savings by about 30%. For example, when we say the Cervélo S5 saves 9 Watts compared to the S3 when riding alone, it means you’ll save about 6 Watts when drafting in a group.

- See more at: http://www.cervelo.com/en/engineering/a ... QaDqx.dpuf

[highdraw]

IchDien,
You got to get a job in pro cycling. 80% of the pro peloton are doing it wrong! All the guys drafting could ride a lot harder in that draft according to you because of the incredible savings of riding an aero bike in a draft. You may have forgot that most don't need a lot of help in a draft because riding in a draft dramatically reduces air drag and probably saves 99% of any contribution due to riding an aero tube bike. But I guess that doesn't matter. Hell on flat stages, even I could hang in the pro peloton in a draft on a fat tube bike. With a 30% savings, maybe I could even be a contender against most of the peloton on fat tube bikes!

[IchDien]

It's not according to me it's according to scientific study, mate.

Either way, seems like you've made up your mind - I'm just pointing out that some Engineers might disagree with you.

[highdraw]

No mate, you simply aren't interpreting the data properly. 'Marketing' of percentages is meaningless. You need to use magnitude of watt reduction to put savings in perspective. 30% of a small power output which btw, I would challenge but even if true is a fraction of a small power output in a draft and if well underneath FTP, it is pretty much meaningless to a fit rider.

In summary, you are saying that Cervelo's marketing blather eclipses the testing of pro teams which race for a living.
Reality doesn't lie and statistics obfuscated by marketing to sell more bikes many times does.

[IchDien]

I seem to recall hearing Magnus Bäckstedt talking about the new Giro Air Attack on Eurosport once. He said something along the lines of "If it's true that it saves around 4 watts, well you can train an entire season and not improve 4 watts, so I'd certainly be wearing one."

I doubt small numbers are "meaningless to a fit rider".

[rijndael]

It's interesting to see folks work so hard to save a couple of grams on the bike+rider weight, when the overall weight is ~80,000 grams, and yet we're not willing to use the same methodology with aerodynamic savings.

[ITTY]

Highdraw, it seems as if you think the whole field of aerodynamics is a marketing scam. Many of the engineers that design these bikes are coming from aerospace backgrounds. I suppose all of the features you see on, say, a Boeing 787 are just marketing tricks too. Maybe we shouldn't worry about the aerodynamics of cars either, since their engines can produce plenty of power to overcome drag.

The point is, improving the aerodynamics of a bike will help by reducing the amount of power a rider needs to overcome aero-drag. This sometimes saves an insignificant amount of power, such as when drafting... But it still saves the rider power

[SkippyMcJimmelstein]

http://www.cervelo.com/en/engineering/ask-the-engineers/aero-in-the-peloton.html

Asker Jeukendrup (High-Performance Cycling, 2002) measured a 30% decrease in power required while drafting, compared to riding alone. This roughly matches the drag savings we’ve measured on the road with our on-bike instrumentation. This decrease is due only to the reduction in aero drag when drafting, as nothing else changes: mechanical friction and rolling resistance are unaffected by drafting.

Most drag-yaw charts are taken from wind tunnel test data for a single bike, not drafting. This data is usually the source for the most commonly cited drag savings. So when you’re in a group, discount the drag savings by about 30%. For example, when we say the Cervélo S5 saves 9 Watts compared to the S3 when riding alone, it means you’ll save about 6 Watts when drafting in a group.

- See more at: http://www.cervelo.com/en/engineering/a ... QaDqx.dpuf

Thanks that's pretty interesting.

Anyone speculate how the Tour Mag results would change if they used a full body mannequin? 70kg human?

[kgt]

I totally agree with highdraw.
What the guy simply says is that in cycling "aero does not equal faster". There are dozens of other parameters that one should take under consideration as well.
It's not an car, it's not an airplane (it's not superman either) it's a -tiny profile- bike with a -huge profile- moving rider on top of it.

[Imaking20]

This seems like it's become the "angry highdraw" thread.

You're not going to convince anyone here to choose a different genre of bike. I'm sure you can drop us all like a bad habit. I'm also sure that I can let 5 psi out of my tires and offset the wretched existence that is an aero seatpost.

[highdraw]

Highdraw, it seems as if you think the whole field of aerodynamics is a marketing scam. Many of the engineers that design these bikes are coming from aerospace backgrounds. I suppose all of the features you see on, say, a Boeing 787 are just marketing tricks too. Maybe we shouldn't worry about the aerodynamics of cars either, since their engines can produce plenty of power to overcome drag.

The point is, improving the aerodynamics of a bike will help by reducing the amount of power a rider needs to overcome aero-drag. This sometimes saves an insignificant amount of power, such as when drafting... But it still saves the rider power

Sorry you don't know my background. Suffice to say, I know the differential equations behind the fluid dynamics. Do you?
I explained above why saving a handful of watts above 30mph is less beneficial than the overall reduction in power transfer and ride comfort deficit contributing to rider fatigue and loss of performance. This seems to be a major blind spot for many that favor aero frames. In fact, if you want a further manifestation is pros move even further away from an aero bike on the cobble classics races. In the TdF this year the best riders were on endurance geometry bikes for these stages which are even less aero. I am sure they thought long and hard about shifting to aero bike for the cobble stages...lol...even though they ride the cobbles faster than anybody here can ride on smooth roads.
Btw, I am a fan of aero wheels and even helmets because they are not fraught with the same tradeoffs of a frame. Perhaps you wouldn't understand that either.