Boost

Boost is a hub and axle standard used primarily on mountain bikes that widens the spacing of the hubs to improve wheel strength, stiffness, and tire clearance. Specifically, Boost hub spacing is 110mm wide at the front (replacing 100mm) and 148mm wide at the rear (replacing 142mm). This wider spacing allows for improved spoke angles, resulting in a stiffer wheel build, and also enables the use of wider tires and shorter chainstays.