i was out for ride to work and then a stop by the pub today, and while at the pub a crew of 12 or so with Harleys where scattered about on the front deck of the pub. i asked a few of the guys if they knew much about motorcycle engines and well, to make a long story short... we cranked the bike up and have come to the conclusion that it's the drive, bearings, internal sh*t, etc. that makes that noise. they mentioned even their Harleys have a similar noise.
it's just annoying, to say the least. guess Soren is right, just need louder pipes. any of you "carpal tunnels" know how to make a pair of specialty spares louder?
thorn