I've always liked the Shamal, too. It's too bad Campy discontinued it. IMO, their current wheel line-up is pretty lame in comparison to the Ventos and Shamals of old. The only decent aero wheel they make is the Bora and it's way overpriced and the rear wheel is difficult to impossible to true due to the 3-spoke lacing pattern.

I've read the same report. Many praises for the Shamal. It's kind of a double edged sword that they've been discontinued. When they're on sale, they're really cheap. But they're rarely ever being offered.... *sigh

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Proud member of Team Tooth Pick (TTP): like a leaf in the wind.

i'd second your opinion.

they last awhile, though with time the super high tension in the spokes tends to create stress cracks in the rim. sadly, there are no 38mm Alu rims available. i only see some 30mm from Araya or Velocity, and the true aero benefits don't start to kick in 'til ~40 or so.

the Mavic Cosmic are pretty similar in concept, weight, and aero numbers, except they use a low profile rim and a non-structural plastic fairing. i really don't understand why they decide to make a weaker wheel that weighs the same, and then charge almost a grand for it. even less why some people will actually buy it.

but more than the aero bit i liked the look of old shiny Shamals... you've to shell out big $$ now to get marginally close. boo-hoo

I don't remember the characteristics of the Shamals, but how about the American Classic 420 wheels? They seem to be a "greater than 30 mm deep, Al rim, few(er) spokes".

http://www.amclassic.com/420_Wheels.html

Horia

the 420 is a deep rim but...

1. the profile is rounded
2. exposed nipples (eek!.. but you know what i mean!)
3. rather weak in 16-spoke configuration

to elaborate:

1. the air foil needs a pointy tail to avoid streamline delamination and ensuing turbulence.

2. the top of the wheel is moving at 2x the bike's velocity, and exposed nipples create some additional turbulence. Campy engineers were rather astute in realizing this, and so used nipples hidden inside the rim

3. to build up a reasonably strong wheel, you need to put sufficient tension into the rim to support the rider's weight and additional road impact. for a low-profile rim and 32-36 spokes, the road contact patch exerts a force on the tire and rim, while the latter distributes the load over several spokes - approximately 4. with about 100kg tension in each spoke, it yields a wheel that can withstand >400kg of impact force, provided the rim doesn't buckle. now, imagine you've a wheel with 16 or even 12 spokes! the tall profile does in fact increase the load-bearing capacity of the rim itself, and spreads the load over a greater circumference of the rim. however, there are fewer spokes.
Long story short, about 2 spokes bear the load at any given time, and you've to put nearly 200kg tension in them. This is much closer to the elastic limit of the spoke, and proves to be very stressful for the rim. The point of this being that the thin walls of the 420 probably would not be able to adequately support that type of load at the spoke hole.
(incidentally, this is why double-eyeletted double-wall rims are better - the spoke load is distributed over twice the material than you'd have otherwise. CXP33 and Ritchey and most Velocity rims either don't have eyelets or only have single eyelets. you either have to use washers - making the rim in fact heavier than advertised, or run the increased risk of stress fracture...)

Wierd. I've got a set of 16/20 bladed 420's, i've put approximatly 15,000 miles on them the last year and a half between hard racing and training. I'm pretty strong (my sprint is in the low 40's) and i weigh 180, and have never had a strength issue with them. I've only had to true them once. i guess if you're really worried about strength you could get a 18/20, or even 20/24 set.

As for exposed nipple, well, i don't think they've ever slowed me down, and they make the wheel easier to mantian (although i don't really have to mantain them, so this may be a mute point). Don't zipp and hed, both more respected than campy in the aero wheel market, use exposed nipples?

ermm.... 'til "40" of what?..

i'm not making stuff up. published drag numbers are usually for 20mpg wind speed, with or without wheel rotating. significant benefits start appearing roughly around 15mph, speed quite reasonably attainable even in uphill time trials, even for web-champions like myself.

adding 10mm to a normal 13 or even 20mm rim does next to nothing - this is known and has been verified experimentally. a 40mm rim profile, however, contributes significantly. this has to do with how streamlines are established around an object, and the numbers come from extensive aeronotical science. furthermore, a proper airfoil must include a pointy tail to avoid streamline delamination. i studied this sort of thing both professionally and recreationally.

if you're genuinely interested in the subject, do a little bit of googling for ...say... "wheel aerodynamics" and maybe even Kraig Willett's and AnalyticCycling.com analyses. You can plug published wheel drag coefficients into calculators in AC's website...

whether any of this shizzle has any bearing on real-life performance... I recon you can prolly beat me in a sprint or a time trial, since I spend time here debunking myths and low-information-content replies, instead of training. :^)

Ben,

the 420 surely is a mighty fine rim. it's made from special corrosion-resistant alloy. my understanding is that corrosion-resistance comes about from a very fine-grain microsctructure, designed to inhibit crack formation, because corrosion attacks metals at the crack (no wise...cracks!). this allows 'em to draw finer walls without worrying as much about eyelets cracking, spokes pulling through, or rim buckling. result - lighter rim.

from my limited experience, if you race and train, most components go to die at the races, where you can't easily steer clear of potholes and fallen riders. all those uberlight wheels might never see the day of fatigue-induced doom. their high price usually precludes people from using them for training, so, limited race use is what they see, and are designed (and priced) accordingly.

my current set of Shamals is... >10 years old, i think from the first year they were introduced; they saw much use, though obviously, from the time i spend here, not enough.

do let us know how the AmClassics do in the long run!

PS: the hidden nipple thing... it's obviously a small effect, but it may go some way to explain why the Shamal has such "anomalously" low drag numbers, compared to other aero wheels of similar depth. Makes truing more of a pain though.

How have your 420 hubs held up? I've read a lot of reports of rear hub problems. It's too bad AC doesn't sell the rim separately. I guess they took a lesson from Mavic and decided they could make a lot more money by selling the wheels complete.

I suggest you call them and talk to them about past hub issues, i don't like to speak for other companies on a forum that is so widely read. They are really good about actually answering phone calls, if you don't get thru the first time, try again a few minutes later.

Besides that, the hubs have been pretty flawless. I did end up upgrading my hub internals to their new engagement mechanism and sealed bearings a few months ago (i am hard on my equipment and expect my stuff to take what i give it, but i also believe in making the small investment to mantain what ive got), i have been very satisfied. I've put mabe 4000 base miles on the new internals and plan racing them for this years road season and any tri's/tt's that i end up doing. I also ride amclassics on my mtb (there new mtb wheel is awsome, but this is the wrong forum for that) i only have a few races on those but the've been great so far as well.

I don't know about their availability, but I picked up a used pair of Gipiemme Techno 416 wheels from a local who wanted the zoot factor of Campy Vento wheels. After he sold the Gipiemmes to me we did a weight and rim depth comparison, and the Ventos were only about 100 grams lighter and one mm. deeper than the Gipiemme wheels, which he sold to me for about US$150.

I used them almost exclusively through heavy training last year and they are perfectly true to this day. Only problem is the rear freehub body has gotten worn out and none of my local wrenches can figure out how to remove it for maintenance or replacement. Anyone know how? I'd love to get back on those wheels.

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The deeper you get the sweeter the pain. Don't give up the game until your heart stops beating.
--New Order