Gear Combo Guru
Join Date: May 2007
Bikes: Spec' Tarmac (road), Ridley Fenix (commuter & fast tourer), Salsa Mamasita (MTB), CoMo Speedster (tandem), Surly Big Dummy (cargo), Airnimal (folder)
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I actually wrote a detailed review of my wheels, partly because a friend was very interested in buying some himself, and I also wanted to post it on a couple of review websites. Here is my opinion:
I had ordered the Dura Ace WH-7850 C24 CL wheels a little while before my wife and I went for a 10-day trip to the Italian and French Riviera (the Cote d'Azur) this Easter. Fortunately, the wheels showed up JUST in time to take them on the trip - I picked them up from the post office at 6pm one evening, and we left at 8am the next morning. So, I had no time to test them and just had to hope that there wouldn't be any problems.
First, some of the things that I learned before making the purchase that made me decide that these would be the right wheels for me. I read several discussions about all-carbon rims and clincher tires being a bad combination on long descents due to heat build-up in the carbon, plus inconsistent/poor braking on the carbon. Since these Dura Ace wheels have mostly carbon rims, but an aluminum braking surface, this seems to negate these worries, and any other wheelsets that are much lighter than these generally have all-carbon rims. Therefore, these wheels were basically as light as I wanted to go. (Tubular tyres are not an option since I am not a supported pro' racer.)
Second, I was wondering if I should consider a slightly more aero wheel with deeper rims for all-round riding rather than a climbing-focused wheelset. However, I then found an independent test of a bunch of wheels in a wind tunnel. These Dura Ace wheels scored pretty much in the middle of the pack when it came to drag, but they were the only wheels in the test that had not been designed with aerodynamics as their primary goal - all of the other wheels had deeper rims and were at least somewhat marketed as being aero, and yet generally weren't much better than these 24mm-deep Dura Aces. Therefore, these wheels appear to be plenty aero enough given that they are designed as a climbing wheelset. These wheels replaced some 105/Open Pro 32-spoke wheels, and when going down hill they seem considerably more aerodynamic because I get up to speeds above 60 kph (40 mph) a lot more frequently than with the old pair, and hitting 80 kph (50 mph) is not hard at all.
I also like the fact that these wheels use exposed nipples, so are easy to true, somewhat regular spokes so that I can replace one if needed, and Shimano hubs are always easy to service.
Since buying the wheels, I've also discovered that they are considered pretty tough, even by pro' teams. Looking at the pictures from the Paris-Roubaix race, there were at least two teams using the tubular tyre version of these wheels (whose construction is extremely similar). Typically they only use robust, aluminum, box-section rims for this race because of how brutal the cobbles are on the wheels, but apparently the Dura Ace wheels are also tough enough for the pro's to use in such a race. Even so, some people were even using full-carbon, reasonably deep rims this year, including Fabian Cancellara on his winning bike (he used some Zipp 404s), so it seems that in general the teams are moving away from the completely traditional rims for this race.
So, that is the external evidence for these wheels being a good buy. What about my personal experience with them?
The first thing I did after getting them out of the box was to check that the spokes all had even tension, the rims were round and true, and that the hubs were smooth and well-adjusted. They passed all of these tests with flying colours, and in fact they were truer than I can normally build a wheel myself (I've built about 20 wheels in the last 6 months, so know a bit about what I'm looking for here). I then put them on the scales. Shimano's claimed weight is about 1390 grams. They came with rim strips on, and I left those on to weigh them, and they came in at 1450 grams - rim strips can account for up to 30 grams, so this is not far off of the claimed weight, but I was disappointed that they weren't under 1400.
During the trip to the Cote d'Azur, I did about 900 km and 16,000m of climbing (about 550 miles with 50,000 ft of climbing) on all sorts of road surfaces. We were on a lot of back-roads, so many of them were in pretty bad condition (much worse than I am used to with the perfect Swiss roads where I live). We also ended up on some unpaved roads a few times, and probably did about 30km in total on unpaved roads, some of which were not really appropriate for road bikes with 23mm tires, but we were having fun exploring. Overall, these wheels took what I would describe as a real pounding in terms of rough roads, and I certainly didn't baby them - I rode right over bumps and holes in the road when necessary, which was not infrequent. The wheels never went noticeably out of true while on the trip, and I was eager to get them back on the truing stand after getting home. When I did, I was amazed, they were still as true as when they were delivered, and so still truer than I can initially get most wheels that I build. Now I know why the pro teams are happy to use them at Paris-Roubaix. I was seriously impressed that they had taken so much abuse and were still basically perfect. The hubs are also still smooth and don't need re-adjusting. I've since done a further 500 km on the wheels, and have still had no problems or needed to adjust anything.
One other thing that was verified after returning home was the quality of the freehub body. Many wheels are made more lightweight by using a weak aluminum freehub body to mount the cassette on, instead of heavier, but more durable steel. If you use a cassette where the larger cogs are all loose, and are not mounted together on a carrier, then the individual cogs can easily dig into an aluminum body very quickly and are then difficult to remove - I have personal experience of this happening on other hubs of mine. Because of this, Shimano refuse to make any aluminum freehub bodies (edit: see correction in next post), and so to keep this wheelset lightweight they used a titanium body (I believe the axle is also titanium). The cassette that I wanted to use for this trip was a 12-28 that I normally have on my cyclocross bike, but this unusual size combination is only available as a set of loose cogs. I decided to be brave and mount this on my brand new wheels. With the 15,000 metres of climbing that I did during the trip, I put quite a lot of power through the biggest cassette cogs, but when I took it off to put my more regular 11-26 cassette on after I got back home, the titanium body still looked perfect, the skinny individual cogs had barely left any marks - this certainly wouldn't have been the case if it had been made of aluminum. So this also pleased me greatly.
Of course, the wheels don't feel much different from other wheels, but knowing that I lost 400 grams compared to my previous wheelset has a good psychological benefit. I had no perception of them being any stiffer than my previous set, or any comfier, but also no impression that they were any less so. The one thing that I do tend notice about different wheelsets, and pay a lot of attention to, is their sound. I like Shimano hubs because the freewheel is normally almost silent, so I was surprised that this was not the case with these wheels, the rear hub makes a crisp, tinging noise when coasting, it's not particularly loud like some Mavic wheels and others, but is a bit more than I was expecting from a Shimano wheel. However, I've now decided that I like it, and it is certainly different from what I've heard from most other wheels. On smooth tarmac, when standing up and cranking the pedals you can hear the whirring noise from the rims during each power stroke as you rock the bike back and forth that is common with carbon rims. It certainly isn't as pronounced as with some deep-section all-carbon rims that I've heard, but it is there, which is very pleasing to me.
So, aside from being 30 grams heavier than I'd hoped, these wheels have turned out to be excellent in all aspects. I would recommend them to anyone as possibly the best clincher wheel designed to be lightweight but that doesn't make any compromises in terms of braking or durability of the rim or hub. The price is also very good: I got them from a German website for 500 euros (about USD$630).
With these wheels, you have to choose between three tyre types when you buy them - clincher, tubeless, or tubular. Since I'm not a supported pro' racer, tubular has no appeal to me. The tubeless concept is interesting, but the rim and tire are heavier than with a clincher, which more than makes up for the weight of an inner tube so it doesn't seem to yield any weight savings. Apparently with tubeless tires you don't have to worry about pinch flats, but I keep my tires inflated sufficiently so that I can't remember the last time I had one of those. Apparently, the tubeless tires feel or roll smoother or something like that, but I'm quite happy with clinchers in that aspect. The major disadvantages of the tubeless version of these wheel is that they are (1) a little more expensive, (2) I believe you need an air compressor or CO2 cartridge to do the initial inflation of the tubeless tires so that the bead seals with the rim properly, I don't have either so I prefer to stick with the traditional clincher setup, and (3) tubeless tires are becoming a little more available, but there is currently only one manufacturer producing them (Hutchinson, although a few re-branded versions of these are available through other companies), and so choice is limited. I really couldn't see any good argument to go with anything but the clincher version.
All in all, unless you want something super aero' then I don't know why you would choose any other wheel in this price range, and they also beat most wheels that are a lot more expensive.
Last edited by Chris_W; 05-13-10 at 11:30 PM.