Features:
- Factory 4.1 RCT incorporates the FMF Resonance Chamber Technology™ both internally and externally
- Achieves a shorter overall length that is less susceptible to crash damage and complementary to Factory Forward Engineering, moving the muffler closer to the motor to centralize mass
- Constructed from only aerospace grade materials that meet exacting specifications and is manufactured 100% at the southern California factory
- For closed course competition use only.
Fit the models:
| KAWASAKI |
KX 250 |
2025 |
| KAWASAKI |
KX 250 |
2026 |
| KAWASAKI |
KX 250 X |
2026 |
| KAWASAKI |
KX 250 X |
2025 |

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.