Yes, I've read the testing, but people are bringing up items that go counter to what was stated by you and Kiley, I think it's a red herring if a bike can carry (x) without aero penalty, if that item matters to very few. Thanks for your reply.

Actually not in this case. The Torhans bottle doesn't scale down to the 51 B series/DA. The junction between the seat tube and down tube is narrower on the small size so the bottle and cradle don't fit.


You nailed it. This is exactly where we ended up as well

When are we getting the "while I was banned from ST, what shook out at Oceanside" race report????

Yes, decided. I'm not sure you're going to like the answer because I don't think the way I carry my flat kit materially impacts the designs that don't offer integration (in aero terms). These are small and compact items and there's little reason for you to not carry them in a way that is basically aero neutral.

Will you have any type of control bike, like a Cervelo P3, too see how truly aero these new(er) bikes test to an old design?

I believe that's why he is testing the felt

Thankfully we are designing the protocol not everyone else. We did read a lot of the points made, discussed, discarded some/most, used others.
But most haven't been in the tunnel or designed testing so...

To your other post:

Yes a control bike, Kiley's Felt run as first runs & last runs.
We also have 3 zero yaw data points per run.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

Probably sick of all the questions,

IIRC when I tested with Len Brownlie at UW he tested 3 point at 0 yaw, one at minus 3 mph one at 30 and one at +3 mph. These runs were like 6-8 minutes.

Are you varying speed as well as doing yaw sweeps, probably missed it already here but are you testing at +/- 10 degrees yaw?

Cheers,
Maurice

We are not varying the speed as it is pretty simple to calculate from 30mph. We are doing yaw sweeps +10/-10 with a zero at the beginning middle and end.

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Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook

First off, it's steel..and secondly, you don't know the wall thickness of the tubes. Making a judgement of it's "stiffness" based on external looks is an exercise fraught with error.

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http://bikeblather.blogspot.com/

From the Rob English site:

"Frame – My original bike used round tubes that I ovalised. This one uses actual airfoil shaped cromoly. I could only find these in a thicker wall than I would normally use, and so I was reluctant to use tubes that heavy. But upon reflection, I realised that the thicker wall would add stiffness and allow me to use a narrower profile. The downtube is only 14.5mm wide, with an 18mm wide seatmast. Lateral stiffness is maintained by using an ovalised toptube, which being horizontal doesn’t increase the frontal area."

Now, only Rob has ridden the bike AFAIK, but thick-walled ovalised cro-mo would seem to me to be a pretty stiff material to build a bike frame frame out of.

Plus the triangles are pretty small.

I would be very surprised if a lack of 'stiffness' in that frame would be holding back its rider, not that stiffness/flex is a problem in any steel-framed bicycle anyway, with the possible exception of some ultra thin-walled 'specials'.

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´Get the most aero and light bike you can get. With the aero advantage you can be saving minutes and with the weight advantage you can be saving seconds. In a race against the clock both matter.´

BMANX

Exactly. It's a pet peeve of mine when people "ass-U-me" stiffness properties based on section size.

It's the same thing when many assume a carbon bike with aero section tube shapes is undoubtedly stiff in the plane of the frame :-/

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http://bikeblather.blogspot.com/

I would roll it back one step further and ask why we assume less stiff is less fast or less efficient or less anything, especially when it comes with some other benefit.

I've been part of testing where two 'identical' carbon frames with different layups showed a difference in BB stiffness of 2x and looking at the speed/power data from control riders on control courses, we found literally NO repeatable difference in speed for a given power under any of the test conditions including out of saddle climbing and out of corner sprinting (most interestingly the out of saddle climbing actually showed an almost statistically significant improvement in favor of the less stiff bike..but not quite). Similarly we've built wheels with 2x difference in lateral stiffness for similar testing and unless there is rubbing of components, you just can't see anything in the data.

Stiffness is a popular proxy for 'fast' and 'efficient' but I think it's importance isn't as well understood as we might think.

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http://www.SILCA.cc
Check out my podcast, inside stories from more than 20 years of product and tech innovation from inside the Pro Peloton and Pro Triathlon worlds!
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After speaking with the most renowned expert in this field this evening...I'm flip flopping.
There is no way that any results from this test can be regarded with any accuracy.
I'm disseminating information directly from someone who has spent more time in a wind tunnel than probably anyone on this planet.
I'm saying that you guys have wasted a whole lot of time and money.
My apologies to you Dan for carelessly and recklessly speaking too quickly.
I don't believe that any results should be published in any form...because I have complete confidence in the inaccuaracy of the results..now.

My apologies...

John. You need to quit.

Well, you can't leave us hanging! Who is your incredible source?? And how can he speak so confidently without knowing any of the protocols?

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@adamwfurlong

Also, how narcissistic are you that you apologize to Dan, suggesting that he made his decision to (potentially) allow the results to be published here simply because the test had your blessing?

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@adamwfurlong

Don't feed the trolls.

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Any run that doesn't include pooping in someone's front yard is a win.

No you're not, though I assume this was supposed to be in pink. At least I hope so. Actually, there's one person on this forum who probably does have more aero testing knowledge than anyone else here, but most of you don't know anything about him. I won't out him, but I pay very close attention to everything he types. He may have even posted in this thread. I don't know, I'm too lazy to go back over it and look.

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Jim Manton / ERO Sports

what the fuck? this thread took a weird turn.

"there's one person on this forum who probably does have more aero testing knowledge than anyone else here, but most of you don't know anything about him."

i think i know the person to which you refer. i meant to ask him what he thought about it all, but i just didn't get around to it.

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Dan Empfield
aka Slowman

I refer to him as "A Beautiful Mind without the Schizophrenia."

I actually don't know how many aero testing hours he has, but I do respect his opinion more than anyone else here. He's not in the industry.

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Jim Manton / ERO Sports

Cheers,

I discussed this with Brian, basically my thoughts after being to the tunnel X1 and spending 4-8 hours after with Len were that *maybe* "now I know what I don't know"

This is a project which is very tough for you guys, but interesting for the rest of us.

Hit it out of the park tomorrow!

Cheers,
Maurice

The result I think we will see is that we see a "winner", even though I think the numbers will be relatively close. I also think the bikes will each have an "out" for why it didn't test "great", etc. So I think in the end it will be cool to see the numbers and then the ......caveats will come in. X bike didn't use stock setup, Y bike needs rear hydration (or name your caveat) etc etc. So I think having Brian and Heath are going to setup a decently fair protocol. Then I think it's going to be nit picking the data, which will be fun for the guy in the wind tunnel who's famously called out much of the industry for it's processes. A very likely fun and appreciative process to be had.

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Brooks Doughtie, M.S.
Exercise Physiology
-USAT Level II

Any idea/resources on the dimensions of the old Reynolds 531 Speedstream tubeset? The Mike Melton-built aero steel frame I had back in the early 1980s was definitely not as stiff as conventional frames of the time.

Nothing more than I could get from Googling ;-)

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http://bikeblather.blogspot.com/