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Yoshimura RS-4S Stainless/Stainless Full System (No CA)

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  • "Customer service is priority #1 at Rocky Mountain ATV/MC. We value our customers and strive to be the best shopping experience- when you buy from us, you are buying lifetime service."

    -Dan Thomas, CEO and Founder

  • Returns

    We take pride in offering no hassle returns. In the event of a return, please call, email or chat with us to receive a solution to the problem. For apparel that doesn't fit quite right, Click here to see our Fit Guaranteed Program.

  • Warranties

    We will stand behind all products we sell with regards to manufacturing defects in workmanship and material. Most products are limited to the manufacturer's warranty. However, we will do everything in our power to take care of the problem.

  • Have questions?

    Live chat: Click here (Leave email if after hours)
    Call us: 1 800 336-5437
    7am-7pm Mon-Fri 8am-4pm Sat (Mountain Standard Time)

    Yoshimura took the opportunity to create a system that would not only improve performance, but also enhance characteristics inherit in the original engineering, i.e. centralized mass and low-center of gravity. They were able to achieve this through use of the RS-4 Muffler mated to a Full System.
  • Yoshimura Full System includes stainless steel RS-4 muffler with turn-out carbon fiber end-cap, low-volume insert, stainless steel header and tail-pipe, installation hardware, and step-by-step instructions.
  • Improved performance.
  • Centralized mass and low-center of gravity.
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