Mavic XA Pro Carbon 27.5in Boost Wheelset

While it's billed as a traditional trail wheel, Mavic's XA Pro Carbon 27. 5in Boost Wheelset is actually anything but traditional. Which is saying something, considering that we're discussing a brand that has become synonymous with tradition while North American wheel manufacturers blasted off into the stratosphere of wildly unchecked innovation. Instead, Mavic sticks with what works, and the XA Pro Carbon indicates that the brand is finally comfortable enough with carbon technology to trust a full carbon trail wheel for the kind of abuse that favors the latest breed of slack, 5in all mountain bikes. In typical Mavic fashion, the XA Pro Carbon wheels are shot through with an expansive list of technologies whose ultimate aim is to increase drive stiffness without taking away from the rim's slightly compliant bump absorption speed that privileges comfort. Or comfort that privileges speed, if you'd prefer. Ultimately, the wheels strike one of the best balances of efficiency and cushion in the trail market, and they do it while foregrounding Mavic's insistence on safety and reliability. Despite that staid approach, the XA Pro Carbon does represent a pretty drastic change to Mavic's mountain wheel philosophy, so there's a lot to cover however, since the wheels are built with one of Mavic's first full carbon rims, that seems the most appropriate place to start. The rims feature a lay up that targets radial flex read: squishy cushion for unruly runs in order to balance the inherent lateral stiffness of carbon with the forgiving vertical compliance of low profile alloy rims. We like stiff wheels while hammering, but wheels that are too stiff presents issues beyond just comfort. Cushion aside, the lay up's real benefit to aggressive trail riders is that it helps maintain contact with lumpy terrain by absorbing impact through engineered flex, bouncing less, and keeping tires glued to the dirt. The spoke material and lacing pattern helps with that, too, as we'll disc...