Mavic had planned a Crossmax SLR 29 last summer as a 2012 product, but development took longer than they thought so the launch was delayed until now. Initial prototypes simply made a 29er version of the Crossmax, but it was flexy and weak.
Mavic’s engineers said there’s a cubic decrease in stiffness as diameter grows. So, a 29er wheel would be about 39% less stiff than a similarly built 26″ wheel. A 29er wheel also has 40% more inertia, and spokes have a lower frequency but higher intensity stress, which can affect reliability. These are the challenges, skip through to see how they overcame them and more…
They tested more spokes (24 rather than 20), which fixed stiffness but added weight. They also tried stronger spokes and keeping it at 20 spokes, and that gave them the strength they wanted with minimal weight increase. But, in both cases, they noticed cracks appearing in the rim.
Interestingly, Cannondale test riders were saying that with 24 spokes, the wheel was more comfortable because spoke tension could be lower. With 20 spokes it was harder, stiffer and faster. That translates to racier, and that’s what they preferred.
The solution was to increase the thickness of the rim’s sidewall extrusion by 0.6mm. It’s a surprisingly small amount of extra material, but it solved the cracking problem. They also adjusted their ISM 3D milling from what’s done on the 26″ rim to balance strength with weight savings. Great, right? Not yet, this led to driveside radial lacing spokes breaking. They fixed this by giving only those spokes a special bead blasting treatment that increased strength without adding weight. After all this, the wheels held up in their field and lab tests.
Claimed weight for the new Crossmax SLR 29 is 1620g (755g front / 865g rear). Hubs work with all standards – Front 9/15 and rear 9/12 x 135/142 and they’ll come with all axle adapters in the box. And, as spied earlier, there’s a Lefty version, too! Spokes are their Zicral bladed spokes. Should be available in early June. $999.90 msrp.
While the SLR presented the most technical challenges because it had to be super lightweight to live up to expectations, the ST needed to be strong since it’s aimed at the All Mountain category. Surprisingly, Mavic says very little special features were needed to grow the wheel from their 26″ version and it still exceeds all of their test standards. It uses the same hubs as the SLR, the differences are that the rims don’t get the ISM 3D treatment, just basic ISM, and their round Zicral spokes with 24 front and 20 rear. So, while the weight difference between the two sets isn’t massive, but it’s rotational weight so the difference in feel should be more dramatic than the numbers may imply.
Claimed weight is 1710g (825 front / 885 rear) and it works with all axle standards, including Lefty and a 20mm front thru axle…something the SLR doesn’t have, but they come set up for 15mm thru axle front and other front axle adapters are available aftermarket. This and the Crossride 29 should be available in the fall around Eurobike time (late August/early September). $824.90 msrp.
The Crossride brings Mavic’s wheels to the masses. Claimed weight is 2020g thanks to reinforced rims for the larger wheel size. It uses standard spokes and nipples and downgrades to their TS-2 two-pawl engagement system. But it’s only $299.90 MSRP. It comes with 15mm front axle and 10mm QR. Other axle adapters are available separately.
Rim width is 19mm inside on all three. The SLR and SL are available in either 6-bolt or Centerlock disc brake hubs. The Crossride is only available in 6-bolt.
COMPARISONS & ACTUAL WEIGHTS
2013 Mavic Crossmax SLR actual weights: 755g front, 882g rear (with quick release axle endcaps).
2013 Mavic Crossmax ST actual weights: 831g front, 893g rear (with 15mm thru front, quick release rear axle endcaps).
2013 Mavic Crossride Disc 29er actual weights: 968g front, 1081g rear (with 15mm thru front, quick release rear axle endcaps).
Crossmax hubs (left) versus Crossride hubs (right).
Crossmax 6-bolt mount (left) versus Crossride (right).
The SLR’s ISM 3D milling (left) versus standard ISM on the ST. The ST is also painted after the milling, so you’re not seeing the alloy, but the bolder graphics aren’t bad looking.
The various axle adapters. If you’re running a Lefty, you get a dedicated hub. Mavic’s U.S. marketing manager Sean Sullivan said there’s just no way to make the hub convertible to work with Lefty and the normal axle standards.
TECHNOLOGY RECAP
For those unfamiliar with Mavic’s rim and wheel tech, here’s a quick recap of the acronyms:
ITS4 – four pawls in the freehub body, two engaged at all times for a 7.5º engagement. This design is fairly open, which lets their hubs convert to all axle standards using different end caps. Now, even the lower end hubs have a similar design except with just two pawls (TS-2) but works with all axle standards.
ISM – Inter Spoke Milling – machined material off rim between the spokes. ISM 3D has material machined off the sidewalls, too.
FORE – uses the material from the rim to create the threaded nipple hole. That’s why Mavic wheels have those larger nipples. It keeps the rim bed solid, which means its stronger and you don’t need rim tape to go tubeless.
