Just a thought, try cleaning bug splatter from the rotors. This may be increasing advancing blade turbulence or reducing retreating blade stall AOA (transition from laminar to turbulent flow). If no joy do the track and balance, and let us know what you find. If no cyclic, i would guess balance more than track - anything starting to wear like an elastomeric bush? Any chance of a bolt allowing some slipage?
Last edited by Graviman; 11th October 2007 at 15:49.