The work that went into developing the RS-4 muffler design paid big dividends in 2010 with Ryan Dungey winning the AMA 450 Supercross and Motocross Championship series as a rookie in the same year, and again in 2012 with the Yoshimura-backed GEICO Honda team winning both 250 Supercross Lites titles. That same 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.
- Pentagonal-shaped muffler sleeve and aluminum mount bracket.
- Front muffler cap functions as a polyresonant chamber which helps reduce noise.
- Two-stage stepped baffle.
- Durable high-grade stainless steel tapered header and mid-pipe.
- Considerable weight reduction.
- Carbon fiber end-cap comes with a U.S.F.S.-approved spark arrested insert installed in the muffler (most models, see notes).
- Step-by-step directions and all necessary hardware included for an easy installation.
Yoshimura Exhaust Series Descriptions:
Enduro Series: In the mid 90's Yoshimura didn't go to the dirt; the dirt came to Yoshimura. Enduro Series systems are an evolution of Yoshimura's early off road efforts crafting off-road exhaust systems. The Enduro Series are all equipped with U.S.F.S.-approved spark arrestor, forest-friendly noise levels, and are tailpipe emissions compliant. (CARB/EPA tail-pipe emissions compliant; all applications are marked with appropriate EPA noise emissions labels.)
Race Series: If you're looking for that competitive edge, look no further than Yoshimura's Race Series. These exhaust systems are designed with nothing but power in mind. Each Race Series system is developed in accordance with noise compliance regulations imposed by most racing sanctioning bodies worldwide. FOR CLOSED COURSE COMPETITION ONLY; NOT INTENDED FOR STREET USE.
Signature Series: Introducing Signature Series by Yoshimura - an offering of exhaust systems that a dealer can install with confidence. The Signature Series lineup is the answer for today's dealer who is faced with a challenging marketplace. The applications for the Signature Series line cover the entire powersports spectrum, including many off-road applications. Everyone of Yoshimura's Championship Winning Motocross exhaust systems and nearly all of the ATV / Side-by-Side applications are all members of the Signature Series Family. All Signature Series components are tested, documented, and marked as required by federal and state regulations. (CARB/EPA tail-pipe emissions compliant; all applications are marked with appropriate EPA noise emissions labels and certified by an independent laboratory for EPA noise compliance.)
