Mavic's Crossmax SL Pro LTD WTS 27. 5in Wheelset may self identify as an XC race platform, but the adoption of the new 27. 5in wheel standard means that it can also nimbly navigate rock gardens and steep climbs without the wheel flop of its larger, 29er counterpart. Its number one job remains speed, though, and few of the wheelset's features play as large a role in its ability to accelerate and hold speed across varying terrain as Mavic's Inter Spoke Milling 4 Dimensions ISM 4D process. ISM 4D removes excess material in targeted areas so as not affect durability, netting a lower rotational mass and reducing the wheel's tendency to remain at rest. Less inertial resistance means more forward progress, so after you've cleaned that slow, techy line, they'll be ready to fire on all cylinders. While Mavic's ISM 4D is responsible for keeping the rim weight down, the Instant Transfer System 4 ITS 4 rear hub ensures that all that low weight efficiency isn't wasted by sluggish, unresponsive engagement. IST 4 is a four pawl system that alternates engagement between two pairs of pawls. Since both pairs engage at different points in the freehub's rotation, the gap between engagement points falls to just 7. 5 degrees of free play. This nigh immediate engagement is nice for sprinting in finales and while jockeying for position in mass starts, but it really makes its butter on technical climbs that require you to pick through trail furniture and pop over rock gutters. The 17mm monoblonc axle is about as stiff as they come, and it tapers down to 12mm thru axle compatibility to take advantage of the new, more efficient standard of oversized dropouts. The Crossmax SL Pro LTD WTS system is finished with Mavic's new Crossmax Pulse tires, which combine a dual compound build with a fast tread pattern that provides a bit more clearance for mud and debris than the typical hard pack only XC tire. The center strip is built for unyielding speed, though the option to run the PulseCro...