Ask Jaroslav Kulhavý, and he'll tell you - every gram counts in cross country racing. But with XC tracks becoming more aggressive than ever, just being a flyweight wheel is no longer sufficient. Now, wheels need to be as tough and stiff as they are light, with all of the handling characteristics that seasoned trail riders have come to expect. These days, wheels need to be more like the Roval Control SL. When our riders asked us for the ultimate cross country wheels, we knew that they were really asking for some pretty specific features. They had to be lightweight in order to be low in the inertia and weight departments, strong enough to take on rocks and roots on a short-travel race bike, and wide enough so that the tire profile was optimized for both traction and rolling resistance - not an easy feat. To check all of these design boxes, we started looking at our Control 29 Carbon rim to see if we could improve on an existing race-ready wheel option, and we found that using a higher modulus carbon fibre would allow us to reduce the amount of material in certain areas of the rim, while also keeping stiffness the same. In other words, think of it this way: The stronger the carbon fibre you use, the less of it you need, and this equates to less weight with the same levels of strength and rigidity. Through this discovery, however, we're able to add three millimetres to the external rim width, while drastically reducing the overall rim weight, leaving us with one of the lightest rims on the market. Being able to add material and width without a weight penalty also made for a stronger XC wheel, with the added benefit of pairing better with tyres for a significant reduction to rolling resistance. Keeping the Zero Bead Hook design found on the Control 29 Carbon, the Control SL wheelset keeps all the sought-after features that come with this design - added impact resistance, easy tubeless tyre installation, and a better tyre seal on the rim. And with a lighter rim, you're also rewarded with extremely low inertia, and this translates to faster acceleration for the punchy efforts required of XC racing. For the build, we kept with our core design tenants of lightweight and durability, so we made sure not to skimp. Each wheel is built by hand, and while this is somewhat of a lost art, we know that a real person can achieve qualities that a machine simply can't. When hand-building, little discrepancies can be found that would otherwise be missed by a machine, so we took the refined 2Bliss-Ready rim and matched it with our CNC-machined hubs with (24 front and 28 rear) DT Swiss Revolution Spokes. The hub internals feature sealed bearings in the front, and DT Swiss 240 internals with a 36-tooth star ratchet in the rear, making for lightening fast engagement. If you're in need of sub-1400-gram, race-ready wheelset that has handling and strength of a modern trail wheel, the Control SL 29 is the perfect choice.