Silencer Pro Circuit 304 Factory Sound CR 250 2004-2007

Pro Circuit 304 Factory Sound

The Pro Circuit 304 Factory silencer is an absolute classic for all lovers of 2-stroke motocross bikes. It has been on the market for several decades and continues to be listed in the Pro Circuit catalog. Updated each year to fit the latest models, it maintains its status as a benchmark in this field.

Top quality and great sound

The 304 Factory Sound muffler lives up to its name - it produces the distinctive sound reminiscent of the factory bikes from bygone eras, sending shivers down your spine. In addition, Pro Circuit sets the highest standards for robustness and durability with this product.

• Brushed aluminum casing
• Connecting pipe and end cap made of 304 stainless steel
• Easily removable with 3 screws (for changing the insulation wool)

For Supercross fans, there is also the R-304 version, called "Shorty" - a shortened version of the 304, designed for SX and shorter race tracks.

Paired with a Works exhaust from Pro Circuit, you cannot only give your 2-stroke motocross bike a top-notch sound, but also achieve maximum performance.

Silencer for motorcycle, scooter, moped

The silencer or muffler, is an essential part of the exhaust a two-wheeler. Its main function is to reduce the noise produced by the exhaust gases as they exit the engine, thus preventing unnecessary noise pollution.

How does a silencer work?

The silencer is usually a tube with perforated internal chambers that are surrounded by a sound-absorbing material. As exhaust gases enter the muffler, they pass through the openings in the walls of the pipe and are then absorbed by the silencer wool.

Silencer Maintenance

Should you notice that your two-wheeler is getting louder and louder, it's time to replace the insulation wool and exhaust gaskets. Maintenance is relatively easy  and requires only a few tools.

If you regularly maintain your motorcycle or scooter, we recommend purchasing an exhaust plug to maintain the effectiveness and life expectancy of the insulation material.

Tuning Level: Racing

We categorize our products into different performance levels  Original, Sport, Racing and High End , so that our customers can choose the right parts for their setup. It is really important to combine parts that belong to the same tuning level, this is especially true for cylinders, crankshafts and exhausts.

Racing products are designed for a more extreme uses and are developed primarily for racing. Whether you stay at 50cc or increase the displacement, the corresponding Racing parts produce much higher performance than the original parts in order to achieve maximum power.