FMF brings you the high-performance Factory 4.1 RCT Slip-On muffler, specially designed for BETA cross bikes. This model incorporates FMF's exclusive Resonance Chamber Technology™, applied both inside and outside the silencer body, to improve throttle flow and optimize the power curve throughout the rev range. Thanks to its Factory Forward Engineering design, the muffler is moved closer to the engine to centralize mass, while reducing its overall length to limit exposure to shocks in extreme conditions. Manufactured 100% in the FMF plant in Southern California, the Factory 4.1 RCT is designed with aerospace-grade materials, guaranteeing exceptional durability and significant weight reduction. It is also equipped with the RTS (Rapid Tuning System), allowing quick and precise adjustment to the rider's needs. This silencer is the ideal choice for demanding racers looking for performance, reliability and innovation.

Fits on

BETA RR 390 EFI 2020

BETA RR 480 EFI 2020

BETA RR 350 EFI 2021

BETA RR 350 EFI 2022

BETA RR 390 EFI 2022

BETA RR 350 EFI 2022

BETA RR 480 EFI 2024

BETA RR 480 EFI 2024

BETA RR 350 EFI 2020

BETA RR 480 EFI 2020

BETA RR 350 EFI 2020

BETA RR 390 EFI 2020

BETA RR 350 EFI 2021

BETA RR 430 EFI 2021

BETA RR 480 EFI 2022

BETA RR 430 EFI 2022

BETA RR 480 EFI 2022

BETA RR 390 EFI 2023

BETA RR 430 EFI 2023

BETA RR 390 EFI 2024

BETA RR 430 EFI 2024

BETA RR 430 EFI 2020

BETA RR 430 EFI 2020

BETA RR 390 EFI 2021

BETA RR 480 EFI 2021

BETA RR 390 EFI 2021

BETA RR 430 EFI 2021

BETA RR 480 EFI 2021

BETA RR 430 EFI 2022

BETA RR 390 EFI 2022

BETA RR 350 EFI 2023

BETA RR 350 EFI 2023

BETA RR 390 EFI 2023

BETA RR 430 EFI 2023

BETA RR 480 EFI 2023

BETA RR 480 EFI 2023

BETA RR 350 EFI 2024

BETA RR 350 EFI 2024

BETA RR 390 EFI 2024

BETA RR 430 EFI 2024