Yoshimura USA R&D has been directed to developing the current generation RS-4 — a unique design that provides an unrivaled combination of power and a quiet exhaust note. The RS-4 features a Polyresonant duplex chamber, a two-staged stepped baffle and an innovative carbon cone end cap.

The Enduro Series are all equipped with USFS-approved spark arrestor, forest-friendly noise levels, and are tailpipe emissions compliant.

• Pentagonal-shaped sleeve
• Front muffler cap functions as a polyresonant chamber which helps reduce noise
• Two-stage stepped baffle
• Alu muffler & carbon fiber end-cap
• A USFS spark arrestor is included