Myth 2: Loud Pipes Save Lives
Yeah, there are a few situations—like where you are right next to a driver with his window down who is about the to change lanes—where full-time noise-makers might help a driver notice you, but all that noise directed rearward doesn’t do much in the most common and much more dangerous conflict where a car turns in front of you. Maybe it’s the fatigue caused by the noise, maybe it’s the attitudes of riders who insist on making annoying noise, or perhaps loud bikes annoy enough drivers to make them aggressive. Whatever the reason, the research shows that bikes with modified exhaust systems crash more frequently than those with stock pipes. If you really want to save lives, turn to a loud jacket or a bright helmet color, which have been proven to do the job. Or install a louder horn. Otherwise, just shut up.
via A Dozen Deadly Motorcycle Safety Myths – Motorcycle Cruiser Magazine.