John and oogle, thanks for the replies. Oogle, did you experience the pitch up?
John, I just want to clarify what I mean by the pitch up. I am not talking about pitching due to turbulence ie the pitch rate is uncomfortable, harsh, and "normal" given the fact that you are in turbulence and in a ridgid rotor head. This pitch up is associated with other tubulent movements of rolling and pitching down. And it is controlable with cyclic. IFR ships seem to experience a solid pitch up in turbulence when driven by the autopilot, but this can be overcome easily by cyclic.
I am talking about a pitch up phenomena that occurs quickly and unexpectedly and is not controllable by cyclic alone. It, as far as I can gather from those whom have experienced it, often results in a nose up of more than 40 degrees and can be accompanied by hitting the forward cyclic limit, and can even produce a steady red on the most moment indicator. It seems to be best remedied by reduction of collective rather than persisting with cyclic.