Pro Circuit exhaust muffler for Yamaha YZ 125 (2002-2017)

The Pro Circuit 304 Factory Sound Silencer is a high-quality exhaust silencer from Pro Circuit, specifically designed for two-stroke motocross bikes. It offers improved engine performance and reduced noise, making it an ideal choice for riders looking to replace their factory exhaust with a reliable, high-performance component.

This 304 Factory Sound silencer is designed with a longer body than the “Shorty” / R‑304, offering better exhaust flow and additional power at high rpm, while reducing the emitted sound without sacrificing performance.

Its construction combines a 6061-T6 aluminum body with a stainless steel inlet pipe and end cap, providing corrosion resistance and long life even in harsh off-road / racing conditions. The silencer is TIG & MIG welded for greater durability and features double wall brackets and Allen screws for easy repacking of the packing when needed.