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Adorable Furry Hombre
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STILL waiting for you to provide the "legitimate" engineers who agree with you.

How long shall we wait? Can I go get lunch?
Well you know how science and engineering works right?

Someone declares and explanation, and it is your job to prove them wrong. Duh. The fact you don't get this clearly means you're less of an engineer than he is.
 

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I’m not the one making dubious claims about the importance of frame aerodynamics. Am I.
Yes. You are. It is EXACTLY what you're doing.
You're claiming it's of no importance. Which is a claim about it's importance. Yet you've provided ZERO "legitimate" engineers or data to agree with you.

The burden is now upon you. You made the claim. Put up or shut up. I'll go get lunch while waiting for your proof.
 

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'brifter' is f'ing stupid
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When you’re familiar with scientific method, eliminating big confounding factors like that becomes common sense.

Yes, I realize that riding a bike isn’t static. But since I doubt Honda would loan their Asimo robot for such a test, the next best way would be to test wind resistance with the static rider in various stages of pedal stroke.

The upshot is that easily 15-20 different measurements for each frame would have to be taken, at different rider positions at different velocities.

The experiment in the video posted here was comically bad, and is, unfortunately, what the bicycle industry considers to be “research”.
Since the rider is moving (pedaling) you don't think it would make more sense to test w/ a rider moving in the tunnel? Really? :rolleyes:
 

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I’m not the one making dubious claims about the importance of frame aerodynamics. Am I.
Yes, you the "physician" are the one making dubious claims that they don't matter right from the start of the thread so it is on you to to provide evidence to support your make believe bs. There is no lack of studies supporting the benefits of aero. I'm not having much luck finding anything supporting your alternate reality though.
 

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Discussion Starter #146
So you clearly don't understand what strength to weight ratio is. It's an absolute. Period.

And for the umpteenth time you could never build an aerodynamic Ti frame and meet the UCI limit. No one will ever ride a Ti bike in the pro peloton. Sorry. You're so hung up on the UCI limit.... which is irrelevant. Weight is pretty much irrelevant in the pro peloton. Some of them are riding bikes over the UCI limit because they know aerodynamics trumps weight. Heck, a Madone SLR 9 weights a portly 16lbs and the disc version is a hefty 17lbs. Geee why would they choose a 16-17lb bike over a svelte 15lb Ti bike? :rolleyes:
Yes. You are. It is EXACTLY what you're doing.
You're claiming it's of no importance. Which is a claim about it's importance. Yet you've provided ZERO "legitimate" engineers or data to agree with you.

The burden is now upon you. You made the claim. Put up or shut up. I'll go get lunch while waiting for your proof.
That argument is ridiculous.

Someone made a claim about aerodynamics, and I’m calling it BS based on the fact that there is no good research to justify the claim. So it falls upon me to prove the claim wrong?
 

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'brifter' is f'ing stupid
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That argument is ridiculous.

Someone made a claim about aerodynamics, and I’m calling it BS based on the fact that there is no good research to justify the claim. So it falls upon me to prove the claim wrong?
Yep. You need to back up claims, that's just how things work.
 

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It seems you can easily build a Ti bike that is below the UCI weight limit, and that has excellent ride characteristics. The only thing you cannot do with them is build them to be “aero”, which I think most of us agree is a bunch of BS anyway. (At a mere 30-40mph with a large, clunky object - eg the rider - atop the bike, wind resistance from the bike is comparatively negligible)

First post by wasp...

Yes you made the first claim that aero is BS and have yet to provide any proof other than that you are a physician and know better than all the engineers in the world.
 

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That argument is ridiculous.

Someone made a claim about aerodynamics, and I’m calling it BS based on the fact that there is no good research to justify the claim. So it falls upon me to prove the claim wrong?
That "someone" is you! lol
It's your claim all the wind tunnel testing and research is BS.
It's your claim aerodynamics is of no importance.

Those are claims YOU keep making. The burden is upon you to support your claims. That's how it works. Put up or shut up.
 

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Since I have nothing to do for lunch, I'll do his homework.
So Waspinator, go ahead, dis-prove it. And you can't simply call it BS. You must provide data from "legitimate" engineers.

https://www.pezcyclingnews.com/technspec/scott-foil-road-aero-redefined-2/

Scott provided the diagram below to show computer modeled airflow around a round tube, a fully ‘aero’ NACA tube, and a FOIL tube, which gives a good indication of how well the various tube shapes perform to wind coming from straight on.

Cyril told us: “In our first study, we wanted to find out which shape would be the best to optimize our three parameters: stiffness, weight, and aerodynamics. So, I simulated a round tube, a complete NACA profile like in the Plasma, and then I tried to analyze the barrier of the airflow on the tube and the separation. On the round tube, you can see the flow creating a lot of turbulence and separating quite early. Early in this case is in the middle of the tube. That creates a lot of negative force and a big tail with some turbulence. On the complete NACA profile, you can see that there is a very laminar flow around the tubing, which stays attached for a very long time to the tail. The separation is very narrow. That reduces the negative force on the back of the tube.”

As part of my due diligence, I called the Dave Salazar at A2 Windtunnel, who confirmed the Scott’s diagram is on the up. Dave also confirmed that the least aero of all tube shapes is in fact the ‘round’ tube – which generally causes air to separate sooner than a foil shape as it flows past, thereby creating more turbulence and a larger wake which will add more drag.

 

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Discussion Starter #151
So you clearly don't understand what strength to weight ratio is. It's an absolute. Period.

And for the umpteenth time you could never build an aerodynamic Ti frame and meet the UCI limit. No one will ever ride a Ti bike in the pro peloton. Sorry. You're so hung up on the UCI limit.... which is irrelevant. Weight is pretty much irrelevant in the pro peloton. Some of them are riding bikes over the UCI limit because they know aerodynamics trumps weight. Heck, a Madone SLR 9 weights a portly 16lbs and the disc version is a hefty 17lbs. Geee why would they choose a 16-17lb bike over a svelte 15lb Ti bike? :rolleyes:
Yep. You need to back up claims, that's just how things work.
So, according to your logic, I could make some absurd claim about bike materials, make up some overtly flawed experiment, and then require you to prove that my claim is a bunch of BS?
 

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Discussion Starter #152
So you clearly don't understand what strength to weight ratio is. It's an absolute. Period.

And for the umpteenth time you could never build an aerodynamic Ti frame and meet the UCI limit. No one will ever ride a Ti bike in the pro peloton. Sorry. You're so hung up on the UCI limit.... which is irrelevant. Weight is pretty much irrelevant in the pro peloton. Some of them are riding bikes over the UCI limit because they know aerodynamics trumps weight. Heck, a Madone SLR 9 weights a portly 16lbs and the disc version is a hefty 17lbs. Geee why would they choose a 16-17lb bike over a svelte 15lb Ti bike? :rolleyes:
Since I have nothing to do for lunch, I'll do his homework.
So Waspinator, go ahead, dis-prove it. And you can't simply call it BS. You must provide data from "legitimate" engineers.

https://www.pezcyclingnews.com/technspec/scott-foil-road-aero-redefined-2/

Scott provided the diagram below to show computer modeled airflow around a round tube, a fully ‘aero’ NACA tube, and a FOIL tube, which gives a good indication of how well the various tube shapes perform to wind coming from straight on.

Cyril told us: “In our first study, we wanted to find out which shape would be the best to optimize our three parameters: stiffness, weight, and aerodynamics. So, I simulated a round tube, a complete NACA profile like in the Plasma, and then I tried to analyze the barrier of the airflow on the tube and the separation. On the round tube, you can see the flow creating a lot of turbulence and separating quite early. Early in this case is in the middle of the tube. That creates a lot of negative force and a big tail with some turbulence. On the complete NACA profile, you can see that there is a very laminar flow around the tubing, which stays attached for a very long time to the tail. The separation is very narrow. That reduces the negative force on the back of the tube.”

As part of my due diligence, I called the Dave Salazar at A2 Windtunnel, who confirmed the Scott’s diagram is on the up. Dave also confirmed that the least aero of all tube shapes is in fact the ‘round’ tube – which generally causes air to separate sooner than a foil shape as it flows past, thereby creating more turbulence and a larger wake which will add more drag.

You haven’t served up any new information here. Yes, one bike frame can be more aerodynamic than another. That’s not the point I’m debating. You could probably make shoelaces more aerodynamic, but for what purpose?

The point I’m debating is the effect that it has when put in context.
 

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So, according to your logic, I could make some absurd claim about bike materials, make up some overtly flawed experiment, and then require you to prove that my claim is a bunch of BS?
This is what you've done, and they have pretty much proven your claim a bunch of BS.

And this is from a guy who has no interest in an aero bike. Nor titanium.
 

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And this is from a guy who has no interest in an aero bike. Nor titanium.
No, he's got skin in the game. His first post:

being the new owner of a titanium bike (Litespeed T1SL), I cant help but wonder why carbon fiber is now king
Clearly trying to justify his purchase was the most awesomest. (Even though he'll never ride it in the pro peloton)
 

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Ahh, moving the goal posts, in context a first generation venge was 50s faster over round tubes over 40km (see bald guy video again).

Or take a look at the tour magazine tests for context where they compare both aero bikes and non aero bikes along three 100km courses (flat 500m, rolling 1000m, hilly 2000m) and give the numbers and time differences.

Aero bikes (different ones) beat out all other bikes on all 3 courses. Even on the hilly course which favors weight, the heavy venge vias disc beat out the lightweight emonda, though by only a few seconds. The lighter weight +aero canyon bike (fastest time on hilly course) beat the emonda by almost 2 minutes. Two minutes over 100km in a situation where weight is favored. On the flat course the difference between the emonda and the fastest bike (madone) was 3 minutes.

Aero isn't BS, the world is round, earth circles the sun.

8_d6c8070366.jpg
 

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Discussion Starter #158
Ahh, moving the goal posts, in context a first generation venge was 50s faster over round tubes over 40km (see bald guy video again).

Or take a look at the tour magazine tests for context where they compare both aero bikes and non aero bikes along three 100km courses (flat 500m, rolling 1000m, hilly 2000m) and give the numbers and time differences.

Aero bikes (different ones) beat out all other bikes on all 3 courses. Even on the hilly course which favors weight, the heavy venge vias disc beat out the lightweight emonda, though by only a few seconds. The lighter weight +aero canyon bike (fastest time on hilly course) beat the emonda by almost 2 minutes. Two minutes over 100km in a situation where weight is favored. On the flat course the difference between the emonda and the fastest bike (madone) was 3 minutes.

Aero isn't BS, the world is round, earth circles the sun.

View attachment 324531
Anecdotal evidence doesn’t mean diddly when the sample sizes are small. If you’re going to use race results, you need dozens of races to prove the point. A few race results here and there won’t cut it. You need consistent results showing over and over that aero bikes are producing on the average better times than non-aero bikes.

But even in a lab, with a properly designed wind tunnel test, I think you’ll find the difference in forces of drag between an aero and non-aero bike to be negligible.
 

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Banned Sock Puppet
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I already told you, the aerodynamic argument is a bunch of BS. With time trial bikes it makes a difference, but for your regular racing bike, the difference is negligible if any.

Want proof?

Manufacturers are still making top-end road bikes that aren’t designed to be “aero”.

Why do pro riders ride bikes heavier than the UCI limit? Sponsorship.
Aero makes no difference to riders like you and me. But to racers who are sustaining 25+mph, it's a big difference.
 
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