If you know what you’re doing, you can make a 29er wheel by upsizing a 26-inch model. For £625 the stiff, sensibly light Mavic Crossmax ST 29ers prove that Mavic know what they are doing.

When Mavic brought out their new three model 29er wheel range this year, the middle-of-the-range Crossmax ST were the ones that really caught our eye. Unlike the expensive Crossmax SLR, which required some fastidious engineering to get the weight down, the ST’s were simply a supersized version of the 26-inch wheels.

Mavic were satisfied with the results when they tested them, so apart from the size difference, they’re virtually identical to the 26in models. Stiffness is the key test of a 29in wheelset and we’ve been highly impressed, they’re easily the stiffest aluminium 29er wheels we’ve yet tested. They even threaten to give carbon 29er wheels a run for their money.

The wheels arrived the evening before the Bristol Bikefest 12-hour race. Cue some manic last minute tyre and rotor changing. But what better, a 12-hour solo race, to test new wheels?

The Ashton Court course is full of fast and very twisty corners. Wheels need to be stiff for the constant and sudden changes of direction, and light for good speed pickup. The Mavic Crossmax STs ticked both boxes with ease, and impressed me from the first lap to the last.

because they are so stiff, you can really chuck the bike around with very little hesitation from the wheels. There’s no flexing or squirming as the forces do their thing on the spokes and rim.

Accelerating out of the many corners the super quick engagement of the ITS-4 freehub lets you get straight on the gas and powering down the next slither of singletrack. The wheels are tagged for all-mountain riding, so the 1710g weight is about spot on. You certainly don’t want to go too much lighter for such riding, yet for occasional racing (if you’re not a weight obsessed weenie) they’re adequate. I didn’t feel them holding me back, that’s for sure.

Away from the race circuit and back to local trails, we found the wheels really come into their own. You can batter them through roots and rocks and they refuse to bend or twist. We deliberately tried to push them as hard as we could: taking bad lines and riding into ugly ruts and steps. They handled it all just fine.

The rims have taken a few knocks but there’s no dents or dings showing, so they’re clearly tough.

It’s illuminating to compare them with the Reynolds XC 29er carbon wheels we tested earlier this year. The Reynolds carbon wheels are stiffer, yes, but not by as much as you might think. Mavic have really narrowed the gap.

The details

Mavic  took the current ST 26in wheels, released only a year ago, and simply up-sized them. They found the 26in wheel was sufficiently sturdy to deliver enough stiffness even with everything stretched out to the 29in format.

The wheels look great as well. The fat, round Zircal spokes look good, and are laced in a two-cross pattern, radial on the rear driveside.  There’s 24 of them in the front wheel and 20 out back.

The rims are officially UST compatible so it’s a real cinch to go tubeless. Mavic’s FORE technology (spoke nipples thread directly into the rim) leaves the inner wall undrilled so they’re completely airtight. The rims also have excess material milled out between the spokes, which Mavic call ISM. I fitted a pair of the new Schwalbe Racing Ralph tyres and they popped up and inflated first time.

The hubs have been designed to to cope with all the axle ‘standards’ currently available. That means you get a bunch of adaptors in the box so you can fit a 20mm or 15mm bolt-through or plain old fashioned 9mm quick release. The rear hub can similarly be used with a 9mm QR or 12mm bolt-through. Plenty of options no matter what bike you’re fitting them too, then.

I mentioned the quick engagement of the freehub earlier. Mavic use a clever design comprising  two staggered pairs of pawls with a 7.5 degree engagement gives a very low response time to a stomping on the pedals.

Sealing has proved to be good on both hubs, with the cartridge bearings still running smooth a couple of months down the line.

Weight is 1710g for the pair, and that breaks down to 825g for the front and 885g for the rear wheel.

If, like me, your riding consists mainly of typical trail riding with just the occasional race, and you value durability over weight savings, then you’ll find the ST’s a fantastic pair of wheels. I’m so impressed with them that I’m still riding them as I type this review. After a couple of months hard riding, they show no sign of damage or needing any tensioning.

Verdict

Light, stiff and bombproof, the Mavic Crossmax ST are fantastic 29er wheels for trail riding.

Pros

Stiff
Good weight
Look good
UST compatible for tubeless fans

Cons

Bit pricey

More info:  Mavic Crossmax ST 29 page
Weight: 1710g
Price: £625

What Mavic says

“The 29er for real mountain biking

“Versatility at its best. The new Crossmax ST 29 offers a perfect balance of features to go up and down the mountains fast and for a long time. This “real” mountain-bike wheelset will stand use and abuse from the 29er enthustiasts. Worry-free ride!

“Cross-country responsiveness, Cross-mountain strength
Less inertia: optimized rim extrusion, ISM
Stiff system: 19 mm rim, through axles compatible, Maxtal, Fore, Zicral
High energy transfer: ITS-4, Isopulse, UST, asymmetrical rim
Tough as ever
Rim resistance: 19c, Maxtal alloy, Fore drilling, SUP welding
Hubs quality: QRM+ bearings, ITS-4
Strong and light spokes: Zicral
Convenience and reliability of a Mavic UST system
Compatibility: 19c rim to fit a wide range of tyre standards, complete discs and axles compatibility
Ease of use: ready to ride UST standard
Mavic race proven technologies: UST, SUP, Fore, ITS-4, QRM+”