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

Discuss light weight issues concerning road bikes & parts.
gitsome
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by gitsome

I think because drag decreases substantially at slower speeds and so does resistance up front. Thats why it matters almost not at all climbing due to such slow speeds where weight matters more. It matters less though I do not mean to say not at all, just less as you slow down to below 20 from reading I've done.
My wallet is the lightest thing on my bike.

tranzformer
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by tranzformer

"It matters less though I do not mean to say not at all, just less as you slow down to below 20 from reading I've done."

gitsome wrote: but if you average 20-25 over distance it seems the aerodynamics are meaningless



So what is it, meaningless or it matters less? Which one are you going to go with. Many of your posts today seem to be flip flopping on what you are trying to say. There is much data supporting that aero still matters even if it is 'only' 20-25 mph over a distance. Aero even matters when climbing (as you have to go down the other side).


gitsome wrote: Thats why it matters almost not at all climbing due to such slow speeds where weight matters more.


You need to read Cervelo's "Col de la Tipping Point". For a pro that tipping point is 8% (where weight starts trumping aero, anything less and aero wins). For an average (250W) rider it is 5%.

http://www.cervelo.com/en/engineering/thinking-and-processes/weight-vs-aero.html

Why can't you have aero and light together?

gitsome
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by gitsome

Meaningless.. I should have said Less Meaningful going to almost not meaningful at all below 20. OK? Something like that.
My wallet is the lightest thing on my bike.

gitsome
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by gitsome

And yes, I said climbing, I did not say descending, obviously descending matters again, my point was slower speeds in ascent. Please do not put words in my mouth as so many others seem to do on WW these days.
My wallet is the lightest thing on my bike.

tranzformer
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by tranzformer

This question keeps popping up in threads on here over the years when a new aero frame is released. I know DJ has asked it several times. Specialized just did a test. Not a 100% apples to apples but close. Makes sense as we know tube shape is more important than tube size in terms of aero. Enjoy.


http://youtu.be/XE_GKePa3CQ

Zoose
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by Zoose

Watched this the other day and I agree it wasn't too surprising. I was certainly hoping for a miracle when I clicked on it to justify my next bike being a classic shaped steel or titanium bike.

HillRPete
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by HillRPete

Interesting, thought it would be less. Something like a Colnago C59 must be way worse then. Does anyone know if those quickie aero tests are just head-on, or are the results combined/weighed over different yaw angles?

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kbbpll
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by kbbpll

They should have tested this one (1982 Panasonic Aero)
http://panasonicbikemuseum.info/1981-pa ... 6000-aero/

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ultimobici
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by ultimobici

So they compare a Venge, which is designed to be as aero as possible, with a regular round tubed frame from the 1980's? Pointless exercise IMO as they are comparing apples to oranges. Far more relevant would be to compare it to a frame built from aero tubing in the 80's such as a Cinelli Laser Strada.
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Tinea Pedis
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by Tinea Pedis

I disagree and think it gave a great present-day comparison of what you gain (or lose) in an aero frame (which isn't the top of the 'aero tree' either) versus a standard round tube offering.

As I am sure there are plenty more riders tossing up between an aero frame or a standard frame as opposed to a Venge or a Cinelli Laser Strada.

ghisallo2003
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by ghisallo2003

Good video.

For completeness, and to understand the interplay of variables, I would like to see the old wheels used as the reference set also.

mjduct
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by mjduct

The thing that is missed the most in a wind tunnel
Are all the small accelerations to cover moves and close gaps during a road race and even casual group rides. Weight, esp. Rotational weight matters way more when giving a little kick to move up a bike length or two in a group.


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micky
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by micky

Tinea Pedis wrote:I disagree and think it gave a great present-day comparison of what you gain (or lose) in an aero frame (which isn't the top of the 'aero tree' either) versus a standard round tube offering.

As I am sure there are plenty more riders tossing up between an aero frame or a standard frame as opposed to a Venge or a Cinelli Laser Strada.


I would add aero sloping frame vs aero no-sloping frame.

rijndael
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by rijndael

mjduct wrote:Weight, esp. Rotational weight matters way more when giving a little kick to move up a bike length or two in a group.


Not really:
http://www.slowtwitch.com/Tech/Why_Whee ... _2106.html

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53x12
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by 53x12

ultimobici wrote:So they compare a Venge, which is designed to be as aero as possible, with a regular round tubed frame from the 1980's? Pointless exercise IMO as they are comparing apples to oranges. Far more relevant would be to compare it to a frame built from aero tubing in the 80's such as a Cinelli Laser Strada.



I disagree. It was a great comparison. On the internet when aero is mentioned and a discussion starts, someone always mentions old school steel frame with small diameter tubes and how they wonder how that would compare against a modern carbon aero frame. Well, Specialized did a test and tried to compare as best they could. It is an apples to apples comparison in terms of the question being answered: small diameter steel vs modern aero carbon frame. Will finally put that response to rest as it has always been replied with tube shape matters more than tube size.
"Marginal gains are the only gains when all that's left to gain is in the margins."

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