[G]

Steering damper....problem solved, although it does sound odd, never read or heard of people having a wobble problem on a cbr600, just lean forwards when accelerating.

It could be something more underlying depending on the age of the bike if bearings etc are going.

Messing with your compression/rebound/preload wont do anything except mess up the way the bike corners and travels, you would be best checking in your book and resetting it all to factory default.