FMF S/s Powerbomb 4-Stroke — Yamaha WR450F/YZ450F

The redesigned PowerBomb is a four-stroke header that incorporates FMF’s patented PowerBomb module at a precise location in the initial stage of the header. By positioning this “Bomb” at a key point in the system, increased performance and flow is achieved through the expansion and contraction of exhaust sonics through the system. Result is a flow increase of nearly 10%! The outer chamber in the Powerbomb allows the air to expand, cool and ramp back up at a higher velocity. Additionally, the PowerBomb is a “pre-muffler” of sorts which helps to lower the bikes sound output by providing more sound absorbing surface area for the sound medium (exhaust gases). On some models, you can choose between a moto or supercross version. The supercross version is designed for more low to mid-range power where the moto version is focused in the mid to upper RPM range.

Header only. The head pipe section. Muffler not included.

This is a 4-stroke exhaust. It is engineered for the 4-stroke engine architecture above and physically will not fit a 2-stroke bike. Verify your engine type before purchase.