High pitch whistle

[bebop]

I haven't had the 06 1600 Classic for very long and have only put on about 1k of the 6k miles. It had V&H Big Shots on it when I bought it that initially masked other sounds since I was not used to loud pipes.

I've been noticing what seems like a faint high pitch whistle in all gears. The pitch gets higher with increased RPMs. It drops lower as I shift to the next gear and then gets higher with the RPMs again. When I pull in the clutch lever it disappears but comes back when the clutch is released. At first I thought I was hearing a distant siren until I realized it was coming from the bike. Now it concerns me that something is not right or maybe there is some kind of air leak.

Is this normal or do I have a problem?

Cheers!