FMF REV Exhaust System Close to stock performance off the bottom with added horsepower in the mid to top range And what a great choice for that high speed outdoor tracks Some torque is sacrificed for the increased RPMs on the top end range Nickel plated for great looks and easy care Note: Rev pipe is only available for 80cc-125cc bikes. The FMF Rev Pipe has been computer designed to provide strong mid to top end power gains. This specialized pipe performs great on fast motocross or supercross tracks for riders who crave additional mid range and a higher RPM power. The FMF Rev Pipe is a must have for 60, 80, and 125 riders that thrive on trackable power delivery and improved peak performance output. Gain a real advantage with this bolt-on power boost!