How to Modify the Exhaust Muffler on a Motorcycle
- 1). Clean the muffler to remove any dirt or oil that has accumulated on it. This can be done by scrubbing the muffler with paint thinner and a wire brush. Steel wool can also be used.
- 2). Sand the muffler with sand paper to further clean its surface and to create a matte finish to which paint will easily stick. Sanding causes the surface of the muffler to roughen so that paint can adhere to it better.
- 3). Paint the muffler with paint meant for high-temperature surfaces. Choose a color that best suits the overall theme and style of the motorcycle. Since the muffler will get hot from the running engine, it is important to use a paint that will not melt in high temperatures. On the 6 inches of muffler closest to the engine, apply a heat wrap. The paint can dry with time, or by turning on and off the engine in fifteen-minute increments.
- 4). Drill holes in the muffler if a different engine sound is desired. This process can create a louder, deeper muffler sound and it is important to make sure the modification adheres to local noise laws (see Resources). Holes can be added by using a 1/2 inch drill bit on the rear bafflers.
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