How to Modify Harley Mufflers
Harley-Davidson motorcycles are known for their rideability, dependability, speed and, of course, loud exhaust. "Loud pipes save lives" is a phrase often used in the motorcycling community, where a lot of times the exhaust of a motorcycle is louder and more attention-getting than the stock horn. Most motorcycles, though, do not come standard with exhaust pipes as loud as those on a Harley. With a simple, do-it-yourself procedure, you can make your own bike sound louder and grab more attention on the road.
- Basic wrench set
- Hand-held drill
- Metal-cutting drill bit
- Rags or towels
- Plastic wrap
Reference your owner's manual to determine how the exhaust is held onto the frame and cylinder head of your motorcycle. Every model of Harley is different, but most exhaust systems will be held on with two bolts per cylinder and one or two mounting bolts at the rear.
Set the motorcycle on its center stand or kick stand. If you have a dedicated work stand, this will make for a much easier exhaust removal process.
Remove the exhaust system of your Harley by removing the mounting bolts from the exhaust mounts with a combination or socket wrench. Cover any openings in the cylinder head with plastic wrap or another water-resistant material to keep moisture and debris out while you work.
Clamp the exhaust system in a vise covered by shop rags or towels. Chrome plating is a relatively thin layer of material at the surface of your exhaust which is easily damaged if put under too much pressure. The rags will save the chrome surface. Install a metal-cutting drill bit 3/8 to 1/2 inch in size to your hand-held drill. Insert the drill into the end of the muffler and slowly drill through the first and second baffles. Do not drill through all three baffles as doing so will require rejetting or resetting the carburetor.
Inspect the tip of the muffler to ensure there are no bits and pieces of metal inside then remove the exhaust from the vise. Reinstall the exhaust pipes onto the motorcycle using the mounting hardware removed previously. Be sure to tighten each bolt to the torque specifications found in your owner's manual.