Thanks for the data!

I guess that the 82 and 108 lines refer to the zipp wheels?

Hmm. Well, I guess that explains why initially only the Stinger 6 and 82 mm data were presented...

If the Jet 90 C2 I bought last month is comparable or close to the Stinger 9 this data just made me a very satisfied customer.

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People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf. George Orwell

so the sub9 is not the only negative drag wheel.....it looks like the stinger 9 goes below the x-axis at 12.5 yaw.

Once again I'll say that data like this becomes important when we start racing in wind tunnels....

Hell, I would bet that nto many people on ST (Ok, Dr. Coggan you would) understand the impact or perhaps lack therof of the data you're presenting.

Once again I'll say that since I started racing in a vacuum I can safely ignore data like this.

Outer space racing is a blast, you should try it! It's the next Big Thing.

"Hell, I would bet that nto many people on ST (Ok, Dr. Coggan you would) understand the impact or perhaps lack therof of the data you're presenting."

That's a fairly disingenuous statement.

At least the new logos look cooler than the older ones....

I wouldnt bet on seeing any data any time soon.
Seems to me the Jet C2's are selling just fine (hell, I just bought a 60/90 wheel set) and HED is having trouble keepoing up with demand, so there is no need to actually provide any data...

I will however, happily stand corrected ;)

what aerobars are those peeking in from the top of the side pic of the wheel?

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Trek Speed Concept 9.9

I wonder if the Jet C2 90 and Stinger 9 models perform similarly, aerodynamically

How so?

If I am wrong, please let the denizens of ST accurately explain what the real world explanation (not-in-a-wind-tunnel) of what yaw angle, grams of drag, etc mean and the impact it will have on their race times, efforts, and rest....Go ahead.

Much like those who profer medical advice to those who ask, there seems a fair amount of aerodynamic interpretation bullshit that flies from the keyboards of many a ST poster. Most of these folks' knowledge of aerodynamics could fit into a thimble and their knowledge base is merely what they are told by reps, ST'ers, or read off of some marketing material.....

I stand by my comment.

Bob

You can win yourself a new HED Stinger wheelset by making closest guess of Bjorn's SavageMan bike split.

There are not a ton of guesses, so this is about the best chance of winning a major prize that you will ever encounter.

http://www.savagemantri.org/Bjorn.html

   
Well, the R.O.T. that Dr Coggan coined, is that a .005 CdA improvement is worth ~20sec over a 40K TT.

So, for example, going from .245 to .23 would net a 1min faster 40K TT.

Well in the real world, which also has wind, just like a tunnel does, less grams of drag, at a given yaw angle, means you will go faster.

There are various online references, not affiliated with any wheel maker, which have done the math showing how much time is saved, for a given power output and drag reduction.

What exactly are you skeptical about? Do you think the "real word wind is somehow fundamentally different than wind tunnel wind, such that no time would be saved by having less drag?

I mean, people have down real world testing on these things too...

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

I'm not skeptical at all, but all of this data lacks one very important item: The Rider.

You can say all you want about the wheel and the benefit it MIGHT bring, but if the rider is set up improperly, has an odd pedaling style, or is simply unfit, these gains will not be seen. I think I've read that 75% of all drag is created by the rider, so if they're causing more drag, wheels aren't going to do pooh.

Bob

If I am a rider whose position Causes Y drag, and my wheels and bike create X drag, my total drag is X+Y.

If I reduce X, there is less total drag no matter how good or bad my body drag is.

There is a valid point, in that a rider might work on their position first, since that will be a cheaper improvement. But either will be an improvement.

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Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter

 
Thanks Jason...are the additional 2 plots also with a 21C Vittoria CX?

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http://bikeblather.blogspot.com/

I hate to say it...but my "gut feel" is that when compared with appropriate sized tires, the C2 version of the Jet 90 will actually have slightly higher drag than a regular Jet 90...especially at lower yaw angles.

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http://bikeblather.blogspot.com/

 
...oh, and I forgot to ask: Do you know if these plots are "normalized" to a standard temp and pressure, and what wind speed are they for?

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http://bikeblather.blogspot.com/

They look like heds, and the jeans look like 501s :)

Do you have a point here or just trying to be argumentative? If you take the same rider with their bizarre pedaling style (what does that mean aerodynamically anyway?) and weird position and put wheels on their bike that have less drag...that rider will go faster. Unfit? Like most of your comments here this is a totally ridiculous non-sequitur.

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The Hed website copy describing the C2 implies that it has lower drag, but I noticed that there are notably no drag numbers supplied.

Hed does supply drag numbers for both the older Stinger 90 and for the Jet 90, showing very similar drag for the two wheels but the Jet is slightly lower.

This thread has a zip-supplied chart that compares the 808 with a "H90" wheel, which I think is the Stinger 90 but I'm not sure, I didn't read the entire thread. It shows the two as being very close but the 808 being a slight bit better.

The curve between that chart and this one for the 808 look a bit different at high yaw angles.

FWIW.

Thanks for posting-interesting stuff. I guess there are two thoughts that come to mind:

1) I really don't see many people going for the 90 over the 60, particularly for a front wheel. There just isn't enough of a difference to make up for the extra side forces (and I say this as someone who's a big fan of using the deepest wheel possible).

2) I realize you're just presenting the data, but at some point, the 808 data needs to be explained. The drag curve doesn't resemble anything other data out there, including the data presented by you earlier (the Trek/Hed data). Is it a clincher, by any chance?