Yoshimura - RS-4 Pro Series/Competition Series Exhaust Systems


  • The next evolution in Yoshimura exhaust, the RS-4 delivers huge power at a very light weight
  • Offers better handling thanks to a lower centralized mass coefficient
  • Uniquely-styled pentagonal muffler body with a carbon fiber cone end cap
  • Front cap design functions as a polyresonant chamber to lower dB output while improving mid- to top-end power
  • Two-staged, stepped baffle
  • Tapered head pipe delivers optimal flow and performance
  • Pro Series features a titanium header construction; Competition Series features stainless steel header construction
  • Competition series mufflers include spark-arrested 96 dB insert
  • Pro Series mufflers include non-spark-arrested 99 dB motocross insert (unless noted)
  • Mufflers available with glossy carbon fiber, satin titanium or brushed aluminum sleeve
  • 99 dB and 94 dB muffler inserts available separately