How to Install Baffles in Motorcycle Pipes

by Kyle McBride
échappements image by thierry planche from

Motorcycle exhaust baffles are important for maintaining the legal status of a bike. The baffle helps to decrease the decibel level of the exhaust note, which can be quite loud. Many areas have laws in place dictating the maximum allowable decibel level of the exhaust. The baffles also maintain back pressure in the system, which aids in exhaust gas scavenging and prevents the release of excessive free hydrocarbons (unburned fuel) into the atmosphere. Areas that require an exhaust gas analysis as part of the inspection sticker process will likely fail an unbaffled bike because of excessive free hydrocarbons.

Step 1

Hold the baffle on the underside of the pipe with the cone portion of the baffle pointing forward and the baffle back end flush or just forward of the end of the pipe. Mark the pipe on the bottom where the cone is resting.

Step 2

Drill a 1/4-inch clearance hole at the cone mark on the bottom of the pipe. Drill a 3/16-inch pilot hole in the cone portion of the baffle.

Insert the baffle into the exhaust pipe. Align the holes in the pipe and the baffle. Install the 1/4-inch, self-tapping bolt into the holes and tighten it firmly. This will pull the baffle cone tight against the pipe and prevent it from rattling because of engine vibration.


  • Adding baffles to drag pipes is a good way to preserve the back pressure and decibel level of the bike while giving it the clean look associated with drag pipes.


  • Use caution when drilling the pipe. Losing control of the drill bit while drilling can allow the bit to "walk" across the surface of the pipe and damage the chrome finish, causing unsightly scratches or peeling of the chrome plating.

Items you will need

  • Baffle set
  • Drill bit set
  • Drill motor
  • Self-tapping, 1/4-inch bolts (one for each baffle)
  • Adjustable wrench

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