My bicycle is very loud, you can hear me pedaling from about a block away, while on a trial. I do this for three reasons, the first being that deer are retarded and if you spook them they'll literally run into you in broad daylight, secondly the last thing I want to do is spook a mountain lion or bear that has cubs while riding around and a loud bike is usually enough to make them scram. Third, so that I don't have to yell up ahead if there are people taking up the entire path.
Note, the paths I usually ride are about a cars width, and when theres three people jogging side by side taking up the whole path, the last thing I want to do is yell at them to make room, so normally theyll hear me coming, look back, then pick a side. It's that rare situation where im biking and theres some fag and his friends wearing full lycra and those ridiculous helmets where I yell ahead, and then they refuse to pick a side to move to until I grind my wheels against theres.
Seriously, anyone that wears lycra outside of the house should just be shot on sight. I've never been a part of or witnessed any bicyclist fights that didn't involve some lycra wearing faggot.