Pirouette. Not Piquoette.
Changing out a clutch should have no effect on how the tail rotor system behaves. Unless you tore apart more of the heli than you needed to, and reassembled it wrong.
Check the usual suspects:
-Binding in the tail rotor pushrod linkage, the tail rotor pitch slider, and/or tail rotor grips.
-Something limiting the full travel of the tail rotor servo.
-Something wrong with the belt drive system to the tail rotor.
-Pirouette spin rate is set by the endpoint adjustment on your transmitter. Max out the rudder endpoints in your transmitter if you haven't already. Overall servo travel is controlled by the Travel Limit adjustment on the gyro, not by endpoint setting on the TX.
-Make sure that the travel limit on your gyro allows you to get the maximum amount of servo travel you can get without binding up the servo and mechanics at the left and right travel extremes.
-Make sure your tail rotor servo is working correctly. When you move the rudder stick side to side, the servo should move very quickly, not poke along. If it seems slow, disconnect the pushrod to see if that makes any difference. If disconnecting TR linkage speeds up the servo's transite time, once again, make sure there is no drag or binding in the TR control mechanism. If the servo is slow with no load, perhaps the servo is about to croak.
Make sure you're initializing the gyro correctly in Heading Hold mode.
Make sure you haven't accidentally enabled revolution and/or acceleration mixing in your transmitter.
* Making the World Better -- One Helicopter at a time! *