4 Stroke

FMF Racing Yamaha WR250F 20-21 Anod Titanium Factory 4.1 RCT SO Muffler w/ R. Carbon Cap - 044474

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...

FMF Racing Yamaha WR250F 20-21 SS Aluminum Factory 4.1 RCT SO Muffler w/ R. Carbon Cap - 044473

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...

FMF Racing Yamaha WR250F 20-21 Hex Q4 S/A Muffler - 044472

A 4-Stroke header system that incorporates FMF's patented Power Bomb module at a precise location in the initial stage of the header system; by positioning the "Bomb" at this key point, the expansion and contraction of exhaust sonics through the system...

FMF Racing Yamaha WR250F 20-21 Powercore 4 Hex Muffler - 044471

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...

FMF Racing Yamaha TTR110 08-24 SS Anodized Titanium Mini Moto Fact 4.1 Slip-On Muffler w/SS Header - 044468

Race-inspired, price-point muffler made for maximum power output. Aircraft-quality extruded aluminum canister with stainless steel components.

FMF Racing WR450F 20 Powercore 4 Hex Muffler - 044462

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...

FMF Racing Powercore 4 Universal S/A Muffler - 040633

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.

FMF Racing Gas Gas 250/300 2018-19/RIEJU MR PRO 250-300 2020-23 Factory Fatty Pipe - 025219

FMF Racing Gas Gas 250/300 2018-19/RIEJU MR PRO 250-300 2020-23 Factory Fatty Pipe

FMF Racing Gas Gas 250/300 2018-19/RIEJU MR PRO 250-300 2020-23 Gnarly Pipe - 025218

Tractor-like bottom end pull, thicker midrange and rugged 18-gauge steel construction.

FMF Racing Gas Gas 250/300 2012-14 Gnarly Pipe - 025152

Tractor-like bottom end pull, thicker midrange and rugged 18-gauge steel construction.

FMF Racing Gas Gas 250/300 2003-06 Gnarly Pipe - 025056

Tractor-like bottom end pull, thicker midrange and rugged 18-gauge steel construction.

FMF Racing Kawasaki KX125 1995-97 Fatty Pipe - 020048

The most copied pipe in the world and #1 best seller for FMF, the Fatty broadens the powerband and provides significant increases throughout.