Just found this on Bicyclesports forum from Mr. Cobb himself.
Yaw is a term we use when testing in a windtunnel. It generally refers to when we rotate the bike in the tunnel so the air hits it from the side. It’s hard to get accurate yaw or crosswind data on an actual bike outdoors because it’s very easy for a rider to swerve 1-2 degrees while they ride down the road in reaction to the cross winds. If you’ve ever followed someone on a windy day you can see how they actually lean their bike into the wind so that it goes straight but when you do that you are actually counter steering a little. That means if the wind is coming from the right, you lean into it to the right but you have the front wheel actually aimed slightly to the left. All of that is why we test in windtunnels to get rid of all the variables. A Spynergy tillium is a nice wheel and a great vlue but not as fast as a Zipp 404. I have preached about H3’s being the fastest front wheel for a long time but as we continue to learn more about wheels and rider habits it turns out that for most TT races there might be a better choice. The original Hed CX, with the curved sisdes was faster than the H3, they don’t sell that anymore. Now the Zipp 404/ Blackwell 58 are about the only deep wheels available with the curved side shape and it will overall be a better choice front wheel. The curved sidewall shape pulls the side air down through the middle of the spokes and builds a better nose shape for the air that exits on the back side. The curved sides also help control air votices that pull away from a non curved rim side which causes some of the steering instability that riders experience.Zipp and Hed both share the patent on the curved sidewall rim shape and that is why other manufacturers can’t use the better shape. Use the Zipp 404 or Blackwell 58 for the front wheel.
Now I just need a light clincher wheelset…Maybe the Hed Alps, American Classic 420, or Spinergy aren’t bad choices now. Why go heavy (H3) and aero when I can go light and aero!
All this talk for a wheel to make me 22.6 seconds faster over 40K…
Maybe I’m missing it, but I don’t see a wheel in the Hed lineup that has the bulge profile that the Zipp has. I think the CX used to have it, but I don’t think any of the current wheels do.
I posted this a couple of days ago. It claims in wind tunnel testing that the Campy Shamal is about the same as a Hed CX but more stable in cross winds. Now Cobb says the CX is better than the Hed trispoke. Then that should mean that the Campy Shamal is just about the best front wheel.
I’m a big fan of the Campy Shamal since I own two and also shouldn’t have sold my CX. But I didn’t realize that the Shamal is this good!
"Use the Zipp 404 or Blackwell 58 for the front wheel. "
Interesting…doesn’t Cobb’s Oval company make the Blackwell…I know he has some relationship with them - just forget what, the BS shop in Minneapolis told me his relationship with Blackwell was tight, if not being an owner.
Is John Cobb the human version of Triathlete Magazine?
This stuff really hurts his credibility. I guess it would be too much to ask that he say H3 is a faster wheel, but we don’t carry that. You should buy the second fastest wheel, the Zipp 404, since that is what we stock.
Not likely I suppose.
Apologies in advance John. We do appreciate your contributins to cycling knowledge in general and this forum in particular.
Apologies my ass. I used to be a huge Cobb disciple. I am not anymore. He has now flip-flopped on everything of any substance he has ever said. First it was seat tubes (round vs. aero) then hydration systems and bottle placement, now wheels. The first two I believed the “further study and analysis has revealed” line but his 180 on HED right after he stops selling their stuff is too wrong and too obvious. I don’t know which, if any, of the bad information he has handed out was motivated by personal financial gain but he has undeniably given out bad information and sold products (and made a profit) based on that bad information. He’s out.
Here’s the real crux of the matter – we’re only talking a minute and half advantage over 40K from standard wheels to an aero wheelset (Hed3, Zipp 404, Hed Stinger, etc.).
I’m trying to convince myself right now that I need a set of race wheels but starting to wonder. I have ALX 320’s on my Felt and they seem plenty fast. The front wheel has 16 bladed spokes but not a deep rim.
I borrowed a buddies Hed Disk and H3 for the last club race and avg. 22.8 mph (16 miles) and in the previous race, avg. 22.5 mph with a CH Aero Cover and my standard front wheel. Is that extra 3/10 of mph really going to make that much of a difference? Worth a $1000? I don’t know. I’m not a pro and definitely not in the Tour…
And I totally agree with CerveloGuy regarding the Aero Disk and love what Ken Lehrer did with his homemade cover on his P2K. Really has to make you wonder if it’s worth spending all that money for a disk. I mean, i could use what I have, cover the rear wheel and have about $950 to do more important things with like pay off some bills. (But what fun is that?). And to think I MIGHT be 5-10 minutes faster in my Ironman this summer with those “race wheels”.
I’m starting to think that my ideal race wheelset would be an American Classic CR-420 Front and a Nimble Spider rear wheel with a monokote cover. I’m figuring I’d save almost a half pound!! that has to amount to something over the distance of a Half or Full Ironman. Right?
You can find a Tilium front for a lot less than the AmClassic. Yeah, it’s heavier, but deeper. There is a 20% off online coupon for performance bike (expires tomorrow), and if you are a team performance member you can pick an additional 10% - making the Tilium SS front only $227.
Hey, is Kraig Willetts out there to give us the biketechreview.com view on the H3 vs. Zipp 404 debate? He’s done some wind-tunnel testing on different wheels and doesn’t have any disabling conflicts of interest that I know about.
HHmmm interesting may not be the right post but I’ll ask anyway…I’ve been cycling for a couple of years now can average about 33-35km/h for a relatively flat Oly, weigh in at about 76kgs 5’11" in height, my bike handling skills are probably about average.
I’m in the process of purchasing a pair of Hed3 carbonlites for my Soloist will be racing in Oly, Half IM and full IM events next season. What do you guy’s think about the new Hed StingerV50 for a front instead of the H3 Carbonlite? or anyone think I’m doing the wrong thing full stop going for the H3 up front??
One interesting aspect of this report is that John only notes the Zipp 404 and the Blackwell wheels. Well, there are at least two other manufacturers out there using the Zipp 58mm rims for their aero wheels, and neither company is mentioned. Zipp is the original, and the supplier of the rims. Everyone identifies them with a good product. Hmmmm…why not mention the other two companies? A cynical man might thing John is just strap-hanging on the Zipp reputation to push his own brand that happens to use the same rims. .
Just seems a lot less than impartial to me. If it were truly impartial he would have mentioned the others.
Personally, whichever way the Zipp or H3 measures come out its probably within statistically insignificant difference. You sure aren’t going to LOSE a race by using either one.
Addendum - and to clarify so as not to upset anyone, H3 was the fastest tested by Cobb in the wind tunnel at A & M across the varying yaw angles, they had the numbers on his old site in the past, I have a copy somewhere. That said, I think there may be efforts out there to bring new aero wheels to market and to advertise and promote them as the most aero available today.
I’m suprised how much stock is put into Cobb’s reports. Yes the guy apparently knows a hell of a lot, yes he’s worked with top pros, and yes he does make a living by selling cycling equipment. I think it’s only fair to read his reports with a bit of skepticism. I think it’s fair to question his objectivity. As a matter of fact I think it’s appropriate, especially since he’s involved in the manufacturing side of things. (Oval for instance.)
It’s not just Cobb. I read Tom Demerly’s stuff the same way. I don’t think these guys are lying, I just know they own bike shops and make money by selling the gear they stock. I think we all need to keep that in mind when reading their reviews. Don’t get me wrong, I love the fact that they are so active and write what they do. I really enjoy reading their stuff. I just read it like an editorial rather than an INDEPENDENT report.
“Y’all want objectivity? Tests cost money - simple as that.”
Amen. For those of you who have never sent Kraig a couple bucks to read one of his reports, I suggest you do. I think they’re fantastic and very worth it. For all the bitching we do for hard data, we still rely on marketing to get our info.
