Description

The Factory 4.1 RCT incorporates the latest in FMF Resonance Chamber Technology™ both internally and externally. In addition, we achieve a shorter overall length that is less susceptible to crash damage and complementary to our Factory Forward Engineering – moving the muffler closer to the motor to centralize mass. The Factory 4.1 RCT is constructed from only aerospace grade materials that meet our exacting specifications and is manufactured 100% at our Southern California factory.
- Available in Natural Aluminum Muffler with Carbon End Cap
- Massive Power gains throughout the RPM range.
- Huge weight savings
- New RTS (Rapid Tuning System)
- FMF uses the highest quality proprietary blend of alloy grade titanium made especially to our standards.
- Can be used with FMF or Stock OEM Header

![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/e5c865f2-9eec-4e80-8be9-11c836f41e31-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/240f29c5-af81-4106-b46a-681b67372cf6-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/bf5735c0-37f1-48a7-bfa2-b9a031c79e1c-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/88fde4be-d575-448e-b7ca-88e9b4e22b5b-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/d6d264e2-2553-456e-8f94-01c56ffdbf16-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/1f93db14-1239-40c5-95c3-377cc4266ad2-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/9519745d-3021-4194-978f-7c8cc91b7856-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/dc279eb0-e092-4c66-9243-5e6802582271-jpg.webp)
![I 4.1 Dual Ti CRF250R 2018-21 w Carb/Cap Slip Ons FMF []](https://boydsassets.specd.nz/uploads/2026/09/0ae577f5-d2f4-460b-ae96-5408cf844117-jpg.webp)




Reviews
There are no reviews yet.