FMF Factory 4.1 RCT Slip-On Muffler 045668 — Beta 350 / 390 / 430 / 480 RR 2020-2026

FMF Factory 4.1 RCT Slip-On Muffler 045668 — Beta 350 / 390 / 430 / 480 RR 2020-2026

Product Description

The FMF Factory 4.1 RCT Slip-On Muffler incorporates Resonance Chamber Technology, utilizing a patented core shape that decreases decibels while preserving maximum power output. Internal ducts within the chambers expand volume for enhanced exhaust flow, delivering power gains across the entire powerband.

Designed with FMF's Factory Forward Engineering to centralize mass and resist crash damage, this muffler pairs a blue anodized titanium canister with a carbon fiber end cap. Fully compatible with stock or FMF headers, it includes a QuietCore 94 dB insert and a spark arrestor to meet AMA and FIM sound requirements.

Top Features: FMF Factory 4.1 RCT

• RCT (Resonance Chamber Technology) features a patented core shape that lowers decibels while maintaining maximum power output.
• Internal chamber ducts increase internal volume for improved exhaust flow and power gains throughout the entire range[cite: 1].
• Factory Forward Engineering design centralizes mass and reduces vulnerability to crash damage[cite: 1].
• Innovative rear end cap allows simple installation of tuning tip inserts or spark arrestors with the removal of four screws[cite: 1].
• Meets AMA and FIM sound requirements, and includes both a QuietCore 94 dB insert and a spark arrestor[cite: 1].

Please review the detailed compatibility data below to ensure an exact fitment match for your motorcycle before finalizing your purchase.

Fitment List

Frequently Asked Questions

Q: Is this slip-on muffler compatible with the stock header?
A: Yes, it is fully compatible with either the stock header or an FMF header[cite: 1].

Q: Does it come with a spark arrestor and quiet insert?
A: Yes, both a spark arrestor and a QuietCore 94 dB insert are included[cite: 1].

Expert Pro-Tip

Expert Pro-Tip: Apply a light film of high-temperature silicone sealant at the slip-joint connection during installation to prevent carbon leaks. Regularly check the four screws on the carbon fiber end cap to ensure they remain secure under high-frequency 4-stroke vibrations.

Recommended Pairings:

• Beta 350 RR Performance Parts & Accessories
• Beta 4-Stroke Performance Parts
• Motorcycle Tools & Accessories

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