Rossier R5 Anti-Reversion II Exhaust for YFZ 450/R has been tested at the AMA pro MX nationals with great results. The Chambers help smooth out the torque curve. On the track, the quad accelerates better and on-off throttle modulation is improved which gives the rider better control. This is not a Resonance chamber like other major manufactures use. These are a full system with carbon fiber endcaps.
The Power Commander 6 will tune your machine perfectly while running the Rossier R5 Exhaust making more horsepower!