Factory 4.1 RCT Slip-On Exhaust Silencer 18-26 Yamaha 450 WR YZ F FX - FMF 044443
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Engineered for serious performance, the FMF Racing Factory 4.1 RCT Stainless Slip-On with Carbon End Cap delivers cutting-edge power gains and significant weight savings. Utilising FMF Resonance Chamber Technology internally and externally, this slip-on muffler shortens overall length to reduce crash vulnerability and enhances mass centralisation, thereby improving handling. Crafted with aerospace-grade aluminium, stainless steel, and a carbon fibre end cap, each unit is manufactured at FMF’s Southern California facility. Features advanced FMF Resonance Chamber Technology for improved exhaust efficiency and performance, Factory Forward Engineering for centralised mass and better handling, aerospace-grade natural aluminium construction with a durable carbon fibre end cap, significant power gains across the RPM spectrum, and is noticeably lighter than stock systems for enhanced agility. Includes a 94dB quiet insert and spark arrestor (screen type) for versatility. New Rapid Tuning System (RTS) for quick adjustments. For closed course use only. Item ID: 044443. Type: Slip-On. Configuration: Single. Construction: Aluminium (muffler), Stainless Steel (midpipe), Carbon Fibre (end cap). Finish: Natural. Includes: Screen insert spark arrestor, 94dB quiet insert.
- SKU
- 06-1784.SIL.FAC
- Brand
- FMF Exhausts
- Availability
- In Stock (5)
Fitments (28)
| Make | Model | Year |
|---|---|---|
| YAMAHA | WR 450F | 2019 |
| YAMAHA | WR 450F | 2020 |
| YAMAHA | WR 450F | 2021 |
| YAMAHA | WR 450F | 2022 |
| YAMAHA | WR 450F | 2023 |
| YAMAHA | WR 450F | 2024 |
| YAMAHA | WRF 450 | 2019 |
| YAMAHA | YZ 450F | 2018 |
| YAMAHA | YZ 450F | 2019 |
| YAMAHA | YZ 450F | 2020 |
| YAMAHA | YZ 450F | 2021 |
| YAMAHA | YZ 450F | 2022 |
| YAMAHA | YZ 450F | 2023 |
| YAMAHA | YZ 450F | 2024 |
| YAMAHA | YZ 450F | 2025 |
| YAMAHA | YZ 450F | 2026 |
| YAMAHA | YZ 450FX | 2019 |
| YAMAHA | YZ 450FX | 2020 |
| YAMAHA | YZ 450FX | 2021 |
| YAMAHA | YZ 450FX | 2022 |
| YAMAHA | YZ 450FX | 2023 |
| YAMAHA | YZ 450FX | 2024 |
| YAMAHA | YZ 450FX | 2025 |
| YAMAHA | YZF 450 | 2018 |
| YAMAHA | YZF 450 | 2019 |
| YAMAHA | YZF 450 | 2020 |
| YAMAHA | YZF X 450 | 2019 |
| YAMAHA | YZF X 450 | 2020 |
- General Product Group
- Exhaust Systems & Parts
- General Product Type
- Silencer
- Variant Id
- 209409
FULL DESCRIPTION
FMF Racing Factory 4.1 RCT Slip-On Exhaust Silencer with Carbon End Cap
Experience a significant boost in performance and a reduction in weight with the FMF Racing Factory 4.1 RCT Stainless Slip-On. This advanced exhaust system is engineered for competitive riders seeking maximum power gains and improved handling.
Key Features:
- FMF Resonance Chamber Technology™: Utilizes internal and external resonance chambers to optimize exhaust efficiency and deliver superior performance.
- Factory Forward Engineering: Designed to centralize mass, leading to improved handling and a more agile ride.
- Premium Construction: Features aerospace-grade natural aluminium for the muffler, stainless steel for the midpipe, and a durable carbon fibre end cap.
- Power Gains: Expect substantial power increases across the entire RPM range.
- Weight Savings: Noticeably lighter than stock exhaust systems, enhancing agility and maneuverability.
- Versatile Inserts Included: Comes with a 94dB quiet insert and a spark arrestor (screen type) for adaptable use.
- Rapid Tuning System (RTS): Allows for quick and easy adjustments to fine-tune performance.
- Closed Course Use Only: This product is intended for competition on closed courses.
Specifications:
- Type: Slip-On
- Configuration: Single
- Muffler Construction: Aluminium
- Midpipe Construction: Stainless Steel
- End Cap Construction: Carbon Fibre
- Finish: Natural Aluminium
- Included Accessories: Screen insert spark arrestor, 94dB quiet insert
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Check the fitment table on this page against your make, model and year. Not sure? Call or email us and we will check it for you before you order.
UK delivery is £4.99, or free on orders over £60. Orders ship within 3 working days, then delivery takes 2–4 business days. Delivery details
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