Features:
- The Factory 4.1 RCT incorporates FMF Resonance Chamber Technology™ both internally and externally
- Shorter overall length that is less susceptible to crash damage and complementary to FMF's 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 FMF's exacting specifications and is manufactured 100% at their Southern California factory
- Massive Power gains throughout the RPM range.
- Huge weight savings
- New RTS (Rapid Tuning System)
- Includes MegaBomb header
- Includes spark arrestor screen insert
- NOTE: Will not pass 2025 FIM sound regulation
- Features stainless steel header with titanium midpipe.
Fit the models:
| GAS GAS |
EC 350 F |
2021 |
| HUSQVARNA |
FE 350 |
2020 |
| HUSQVARNA |
FE 350 |
2022 |
| HUSQVARNA |
FE 350 |
2023 |
| HUSQVARNA |
FE 350 |
2021 |
| KTM |
XCF-W 350 |
2021 |
| KTM |
XCF-W 350 |
2022 |
| KTM |
XCF-W 350 |
2020 |

FMF - Flying Machine Factory - 1973 was founded by a twenty-two-year-old named Donny Emler, a typical Southern Californian who, like everyone else in the 1970s, found a passion for riding and racing dirt bikes. FMF is now one of the most recognizable logos in motocross. The main area of FMF is the highest quality exhaust systems for dirt bikes.
| Brand |
Model |
Year |
Name |
CC |
| HUSQVARNA |
FE |
2020 |
|
350 |
| HUSQVARNA |
FE |
2020 |
|
350 |
| KTM |
XCF-W |
2020 |
|
350 |
| KTM |
XCF-W |
2021 |
|
350 |
| HUSQVARNA |
FE |
2021 |
|
350 |
| GAS GAS |
EC |
2021 |
|
350 |
| HUSQVARNA |
FE |
2021 |
|
350 |
| KTM |
XCF-W |
2022 |
|
350 |
| HUSQVARNA |
FE |
2022 |
|
350 |
| HUSQVARNA |
FE |
2022 |
|
350 |
| HUSQVARNA |
FE |
2022 |
Rockstar Edition |
350 |
| HUSQVARNA |
FE |
2023 |
|
350 |