Dayco XTX2251 ATV Belt Built for the most extreme machines, Dayco XTX ATV and UTV belts are engineered for machines powered by 800cc and above engines. Engineered with specially-formulated, high-temperature polychloroprene with the highest level of Aramid fiber reinforcement available delivers track-churning performance for the most aggressive riders. This innovative break-through design features deeper cogs on top and rounded cogs on the bottom for ultimate flexibility and longer belt life while being a better alternative to the original equipment belt. Faster and more consistent throttle response at high speeds. Quicker throttle response at mid-speed acceleration.