T4 is designed for stock or slightly modified 4-stroke engines. Unleaded and ethanol-free, T4 is a direct pour-in replacement for premium pump gas, which has a short storage life and has caused a heightened need for repairs in all engines after periods of non-use. While riders facing extreme conditions are forced to add octane boosters or race fuel to increase the octane of pump gas, T4’s 97 octane rating (R+M/2) provides greater protection against detonation. (Compared with more expensive performance parts that increase power along only a small slice of the power curve, T4 offers 2-3% more power and better throttle response across the entire RPM range.)