FMF Beta 390 RR-Race Edition/390 RR-S Q4 Spark Arrestor Muffler
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FMF Beta 390 RR-Race Edition/390 RR-S Q4 Spark Arrestor Muffler
The FMF Beta 390 RR-Race Edition/390 RR-S Q4 Spark Arrestor Muffler is an FMF dirt bike and ATV performance exhaust component. It is listed for Beta 390 RR-Race Edition/390 RR-S applications shown below.
A 4-Stroke header system that incorporates FMF's patented Power Bomb module at a precise location in the initial stage of the header system; by positioning the "Bomb" at this key point, the expansion and contraction of exhaust sonics through the system resulting in a flow increase of nearly 10%. The surface of the perforated core lets the sound exit into the absorbing material (steel wool packing) and then allows the air to expand, cool and ramp back up at higher air pressures (RPMs).
Key Details
- Product type: Q4 Muffler
- FMF series: Q4
- Manufacturer part number: 045667
- FMF performance exhaust component for dirt bike, ATV, or powersports use as applicable
Fitment Notes
Match the exact year, make, and model in the table below before ordering. Exhaust routing, mounting points, engine configuration, and emissions equipment can vary between model years and trims.
Fits These Models
| Year | Make | Model |
|---|---|---|
| 2020-2025 | Beta | 390 RR-Race Edition |
| 2020-2023 | Beta | 390 RR-S |
| 2020 | Beta | 430 RR |
| 2023-2024 | Beta | 430 RR |
| 2025-2026 | Beta | 430 RR X-Pro |
| 2020-2025 | Beta | 430 RR-Race Edition |
| 2020-2023 | Beta | 430 RR-S |
| 2020 | Beta | 480 RR |
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