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...

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...

The PowerCore 4 was developed to increase the horsepower and torque throughout the entire power curve producing a noticeable power increase that is useable and compatible with every style of riding. Aluminum construction and stainless steel Hi-Flo end...

The Factory 4.1 exhaust system with the Powerbomb header is FMF's premier exhaust system. This system is perfect for the track or dunes, and is used by factory teams such as KTM, Epic Can-Am and Rath Racing. The Powerbomb header is made of durable...

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...

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...

The PowerCore 4 was developed to increase the horsepower and torque throughout the entire power curve producing a noticeable power increase that is useable and compatible with every style of riding. Aluminum construction and stainless steel Hi-Flo end...

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...

The ultimate power boost, the MegaBomb Headers improve performance along the bottom and mid-range powerband. Patented FMF technology combines the benefits of a longer header, with top end peformance of a shorter header.

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...

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...

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...