Mavic Crossroc Mountain Wheelset 27.5650b. Open up a whole new element to your mountain biking game with a pair of Mavic Crossroc 27.5650b wheels. With their innovative and totally dialed in Wheel Tire System WTS, Crossrocs match Crossroc Roam tires to lightweight, hammer hardened alloy rims for a feel that is fast and fun. With QRM sealed cartridge bearings and stainless straight pull bladed spokes, you'll enjoy season after season of action packed, maintenance free riding no dirt, no water, no grime is getting inside these hubs. And remember, whenever you're ready, this WTS is tubeless ready...just seal them up and go.