whoever said that the debate over "loud pipes save lives" has gone on forever is right, in two ways. One it does save lives and inflate the ego, on the track.
Having rode performance atv's in my teens i believed the same thing for my recreational use as well but when i got older i realized that my boost in performance helped noone but myself! see where im goin with this?
loud pipes are loud because the rider needs the power use a tuned exhaust system brings. Or at least uses their machine to that state of tune most of the time and feels they need to ride that hard.
My MB currently hums right along with its restrictive exhaust, and lacks a bit of power because of it but im not thinking about putting a tuned pipe on it because i hold a constant RPM most of the time and dont have any use for the typical powerband.
Chopper riders i believe have the right to a loud exhaust, as yourself if a chopper really makes sence if it sounds like a techumseh. not really eh.
on the track, a loud exhaust keeps the rider alert to his line, and also helps you stick to the rider ahead of you because you know when hes on the gas therefore YOU should be on the gas if your gonna catch em! this is how i raced competitive 125 dirtbikes 4 years ago. which diffuses the (noise is all behind you" comment somewhat.
anyway, off to work where the noise comes from industry.