the noise doesn't bother me as much as it used to, it's just there. of course, if you don't know what it is, there is some concern, because when something goes wrong, it's often an odd noise that tips you off.
interesting that there is some differnce of opinion about its source. i was paying closer attention to it yesterday, and actually found two similar sounds that apparently are from different sources.
one is a whistle you can hear with the bike in neutral, while revving. it's not terribly loud (at least with my bad ears and a helmet on), and is most pronounced when you first roll off the throttle. i assume that this one is air or fuel system - related.
the other is a louder whine, and seems to be drivetrain related, because it disappears when you pull in the clutch while decelerating. it could be the chain, as stated above, or possibly the transmission. whatever it is, i'm assuming it is normal noise that would otherwise be less noticeable, if it weren't for the fairing.
i told the wife that i could always get a louder exhaust, if the noise continues to annoy her. :twisted: