"Loud pipes save lives" is a common phrase used in the motorcycle community, where often the exhaust note of a motorcycle is louder and more attention-grabbing than the horn that it comes with. Loud motorcycle pipes have become a staple of the cruiser motorcycle scene. However, most motorcycles do not ship with the sort of loud exhaust brands like Harley Davidson have become synonymous with. This is, rather, the product of a simple procedure you can perform to your own motorcycle at home.
Use your owner's manual to determine exactly how the exhaust is connected to your motorcycle model. Unfortunately every bike is different, but most will be held on by two bolts at the cylinder head and two at the rear of the bike.
Set the motorcycle on its kickstand or centerstand so it will not tip or fall while you are working. If you have a dedicated motorcycle work-stand, that will provide a much easier means of removing the exhaust.
Use a socket wrench and the appropriate size sockets to remove the exhaust completely from the motorcycle. Cover any open holes in the cylinder-head of the engine to keep it free of moisture and debris while you are working.
Clamp the exhaust system in a vice. Cover it first in shop rags to save any chrome from being damaged or scratched by the metal surface.
Insert the end of your hand held drill with a 1/2" or 3/8" metal cutting bit into the end of the muffler. Drill through the first and second exhaust baffles carefully. Most motorcycle exhaust systems have three or four baffles. Drilling through all of them will require re-jetting the carburettors due to lack of compression.
Remove the exhaust system from the vice and reattach it to your motorcycle using the hardware you removed earlier. Refer to your owner's manual for torque specifications and be sure all bolts are tight. Crank your bike and listen to the new, deep and loud exhaust tone.