The work that went into developing the RS-4 muffler has paid big dividends in Off-road Racing; winning multiple Supercross and Motocross titles since it's inception. We've developed the current generation RS-4 based on that research & development, and the result is a unique design that provides an unrivaled combination of power and quiet exhaust tone. The RS-4 features a Polyresonant duplex chamber and two-staged stepped baffle for increased performance, while a carbon cone end cap finishes off its innovative styling.

• Pentagonal-shaped sleeve
• Front muffler cap functions as a polyresonant chamber which helps reduce noise
• Two-stage stepped baffle
• Carbon fiber end-cap
• Stainless steel tail-pipe
• Weight: 0.3 lbs lighter than stock configuration

Manufacturer Disclaimer: Cannot confirm fitment on international bikes

Fits:

• 2014-2018 Yamaha YZ250F
• 2015-2018 Yamaha WR250F