29 June 2008

bikefix Exclusive Review: Mavic Crossmax ST Disc wheelset

Good, functional products really don't make for great reviews, do they? Much like people watch Nascar for (I imagine) the crashes, people tend to like reviews that expose flaws- after all, nothing is perfect. That said, while it makes for interesting reviews, I certainly don't want equipment drama while out on the road or trail. While Mavic is known for making fantastic rims, their complete wheels have a bit of an uneven history around here. The company's hole-free tubeless rims are very strong and don't resort to a non-structural band-aid to be tubeless compatible. The aluminum spokes are cool looking but can be pricey to replace and difficult to find and the hubs... well, the hubs have required frequent service in our experience. The problem, it seems, stemmed from dissimilar material hardnesses in the cassette body, causing Part A, combined with fine desert grit, to eat Part B with alarming speed. Regular cleaning and maintenance could prevent this, but few have the discipline.

When Mavic announced their 2007 line, a number of improvements were trumpeted. Hub durability was reportedly improved. Effective flange spacing was increased, for better lateral rigidity. One wheel, in particular, stood out. The Crossmax ST was billed a a wheel designed to "withstand the rigors of true mountain bike riding." At 1650g/set, it was about as light as the previous year's race-oriented Crossmax SL, but oriented toward owners of newer 5/5 bikes, who spend as much time climbing as they do descending. At $750, they aren't cheap, but with top-end wheelsets now approaching $1,000, they're starting to look reasonable. Given the number of rock dings in my thin walled first generation (paired spoke) Shimano
XTR wheels, I decided to give the STs a go.

For French wheels (Mavic is based on the shores of Lake Geneva, just down the hill from Les Gets & Morzine), the Crossmax STs are pretty reserved, appearance-wise. Mostly black, there are small logos printed on the rim and a couple of spokes. Because the inner wall of the rim has to be pretty meaty to support the externally threaded spoke nipple, that area has been traditionally overbuilt on Mavic wheels. The company's (no doubt expensive) Inter-Spoke Milling addresses this, removing material from between the spokes and (in this case) leaving a supporting ridge that gives you some idea of just how much material was there (see top picture). Removing material at the rim will have the greatest effect on acceleration, and the company has found a way to do this without sacrificing nipple mounting or overall strength.

Because the nipples are captive on the end of the spokes, the hubs have slotted mounting holes for the spoke heads. This fact contributed to my first problem with these wheels. On a hard(ish) landing, my 160lb load (fully loaded) managed to detension a spoke so completely that it popped out of the hub. Thankfully, as a disc wheelset, I was able to ride out despite a sizable wobble. When I got home, I used the provided proprietary spoke wrench to loosen the spoke, slot it back in place, and true the rim, which was in very good shape considering. Once the wheel was true and round, I added 1/2 turn to all of the spokes on each wheel. The additional tension has stopped any other spokes coming loose and doesn't seem to have had any additional impact. In the 10 months since, they haven't seen (or needed to see) a truing stand.

Since then, the Crossmax STs have been exposed to out local rocky desert terrain, Moab and Portes du Soleil trips and been mounted on several test bikes, with no complaints. The freehub doesn't engage as quickly as some others on the market, but unless you're a trials rider, it really isn't an issue. Every once in a while, it feels like a couple of the pawls don't quite engage properly and slip a few degrees. It makes a godawful noise, but that's about it- it happens only rarely and doesn't seem to have harmed the hubs. After 11 months' use, I decided to pull the cassette body apart to look for damage, dust, broken pawls or broken teeth. Much to my surprise, they inside was clean and pristine. On my local shop's advice, a few drops of mineral oil were added, the wheels reassembles and they were back on my bike within 30 minutes. The sealed cartridge bearings are still running as smooth as they did when new, though their replacement looks to be pretty straightforward. The wheels come with Mavic's excellent composite quick-release levers, which are lightweight and positive in their action.

Complaints? I have a handful. The black paint (particularly on the spokes) is flaking off more than I'd have liked (though it's not too bad), and anodizing would be inexpensive, lighter weight and more durable (though more prone to fading). Also, the axle end caps could do with some knurling or a knurled steel insert (as on WTB's hubs). On occasional awkward landings, the wheel can slip ever-so-slightly in the dropouts, causing discs to rub. The provided computer magnet is a nice bonus, as are the tubeless valve stems. For 2009, the Crossmax ST will be largely unchanged, save for a 15mm through axle taking advantage of Shimano & Fox's open standard. Finally, for an additional 8% of the purchase price, Mavic's MP3 (Mavic Product Protection Plan) offers a 2 year no-fault warranty, which is a heck of a deal for the less careful among us.

All in all, the Crossmax STs are impressively light, 'trail' wheels. They could use a bit more spoke tension out of the box and some minor detail refinement, but these make good use of Mavic's extensive wheel building experience. For riders looking for a light, strong tubeless-compatible wheelset, these would be a great place to start.



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