Maxxis Aspen ST Tire - 29 x 2.25, Tubeless, Folding, Black, MaxxSpeed, EXO, Wide TrailAspen ST Riders have asked, pleaded, and maybe even begged, and Maxxis has finally answered. Starting in time for the 2024 race season, Maxxis is releasing the Aspen ST in two casings, EXO and Team Spec (170tpi). Until now, these tires were reserved only for our top race teams. The Aspen ST is an ultra low profile race tire designed primarily for short track XC use, although we have seen some of our athletes use the narrower 29x2. 25 size on their