I don't get why some people are saying ENVE wheels are not aero. Is it because they don't invests tons of money into marketing the "aero" quality, and have tons of meaningless graphs on their website? There has never been anything to prove they are NOT aero, has there?

I really think the more aero rim comes down to who is going to advertise and market the aero aspect of their rim the most.

It also amazes me how many people sell off their last season wheels because they feel the aero qualities of the rims are slowing them down and they need "faster" wheels. I guess all the marketing hype around each new seasons product is doing the trick!

there has been plenty to prove they are not aero. most times, you get it as "brand E", with HED being "brand H", mavic "brand M", etc. Although Enve doesnt come right out and say it, their whole push with their Smart System wheels shows that they DO invest in marketing the aero quality, but only when the quality is there. independent tests generally back up the fact that zipp, hed, bontrager, and now enve's smart wheels, are faster for a given depth than V-shaped wheels.
who knows, they could all be lying to us. to me, the conspiracy would be harder to pull off than just doing it, however.
and the fact that you dont have a bunch of V-rim makers touting theirs as faster than the "blunt-edge" guys kind of speaks for itself.

So the new Bora Two is bunk?

i havent seen campy produce any wind tunnel data about it.
i dont know if i'd call it BUNK, those wheels sure look very nice, they have the best fit'n'finish of any wheel, i'm sure they feel even nicer, but if every second counts, i'd pick something else.

p.VDB, excellent questions. Sorry it took me a bit to respond but I could only make some crude measurements at home and wanted to check drawings and physical parts.

The answers concerning brake track width are a bit embarrassing. First of all, the 404 number on the web site is actually for the previous-generation 404. Second, the other numbers have been grabbed from the wrong columns in the spreadsheet that was used for the site and our catalog.

Here's the correct numbers for the top and bottom of the brake track (listed as top/bottom)
303 CC: 25.14/27.57
303 Tubular: 25.14/27.57
404 CC: 23.48/25.73
404 Tubular: 23.96/26.34
808 CC: 23.48/25.73
808 Tubular: 25.95/26.24

As you can see, these dimensions are identical for the clincher and tubular versions of the 303, relatively close on the 404, and there's a significant difference on the brake track top measurement comparing clincher and tubular 808. This is what was arrived at through experimentation with the transition from/to tire and rim at each of the depths and tire types.

In terms of the question of whether the clincher or tubular is faster there's no absolute answer. This will depend somewhat significantly on what tire models are being used on each version of the rim, as well as the effective yaw angle in question. Rolling resistance on various tube/tire combinations will also affect these comparisons.

The 404 and 808 (either clincher or tubular) are fastest (aerodynamically speaking) with 21mm tires, though design centered on 23mm tires. The 303 (either version) is still fastest with the narrow tires but design focused on minimizing aero penalties with tires up to 27/28mm wide. Again, like most things in aerodynamics, this isn't a hard and fast rule as it's still tire model-dependent. One company's 23mm tire performs significantly better on each of these wheels than their 22mm tire, for example.

Lastly, I threw together a quick plot of 23mm and 23mm data for 303 and 404 carbon clinchers. Sorry it's not super polished but again it's from our internal database.

Hope this helps, and sorry for the confusion on the brake track widths.

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Zippy engineer

I was just looking for some ride reviews of the Zipp 303 CC. Don't see the fuss about aerodynamics as I don't go 40km/u average on the Tour of Flanders....

Waldo: Thanks for the informative response! I personally don't mind that Zipp is better at building wheels than building web sites.

It seems in summary that the 303's save about 100 gms in weight for the tubbies, but you pay for it with 30 gms of aero resistance. Seems like an obvious choice. Thanks!

Do people really race on 21mm tires anymore?

-Eric

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www.ergottwheels.com

Enve's 65 (probably clincher, doesn't really say) did fairly well in June 2011 when tested by a german triathlone mag. They didn't do a ranking, but the usual suspects of Bontrager, HED, Zipp etc were all in the test.

Here's an ad-hoc translation of the summary ( from http://www.testberichte.de/a/fahrrad-la ... 72632.html ):



The more aero wheels were Zipp's 808 and HED's Stinger 9 if I'm reading correctly, the 404 Firecrest CC was ranked behind the Enve.

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Bikes: Raceur, Beateur

i looked across the link, but couldnt find the protocol on their test. do you have it? most curious about what yaw angles were tested, with a spinning wheel, and if they averaged a range to come out with a score. and with what tires. v-shaped rims do fine at zero yaw.
man, i wish i knew german...

I'd be surprised if the ENVE wheels tested well in yaw conditions. They are real V design, which according to the wind tunnels does not do well in that scenario. I have a set of the 65 clinchers, and think they are great wheels. But, they do like to steer in side winds!

No, sorry, I only stumbled across it in the online tests database.

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Bikes: Raceur, Beateur

Hi Waldo, thanks for your bright reply. The numbers you posted make more sense! The graph you posted with the 303 vs 404 with 23mm and 25mm tyres is very handy! The rims/tyres in that graph are clinchers I presume?

I expected that the 303 with a 25mm was doing better. But my conclusion from your graph is that the 404 is always faster. Even a 404 with 25mm is can beat a 303 with 23mm tyre at some yaws. Is it true that the difference of the 404FC vs 303FC is only one watt? From the graph it looks more?

What combination do you think can take the abuse of rough roads / cobbles during a road race beter: A 404FC with 25mm GP4000S or a 303FC with 23mm GP4000S?

I raced 404 Firecrest tubies this past year. Badass wheels.

I rode 303 FCC for a few weeks here recently. Light wind days, heavy wind days, wet days, dry days. Not badass wheels. Why?

1) Acceleration felt slow. Same with the 404 FCC. Felt like I was trying to ride through thick sand.
2) Cornering at speed wasn't confidence inspiring.
3) I could tell zero difference between 303 FCC and my 101s.

As far as I'm concerned, Joe Rider would be better off purchasing two pairs of 101s. I thought the 303 FCCs would be the end-all-be-all of wheels. It's not. Instead it's outdone by it's aluminum, cheaper little brother.

By the way, my 101s with GP4000s and a PG-1070 cassette are 20g lighter than the 303 FCC with 23mm Tangents and a D/A cassette (both 11/25s).

Bonus info: The new silver brake pads weren't as badass as I was expecting. In dry conditions, fine...they stopped, like most other pads. It was in the wet that I was really let down. I'll stick with Swiss Stop yellows. And 101s. And Firecrest tubies.

Interesting...what tires did you have on the 404FC tubulars?

I'm thinking your relative impressions of the 303 FCCs and the 101s might have more to do with the tire choices than anything else. The Tangentes don't "roll" as well as the GP4000s.

Put some latex tubes inside of some Vittoria Open Corsa CXs on the 303 FCCs, or 404 FCCs and you might be in for a shock.