RE: Hawk Pro Vibrations...
It's always tough to debug vibes...
In spite of never having crashed, I'd still go over all of the shafts; are they all straight?
As I understand, you've pulled both the main rotor blades and flybar off of the head. In this case, does the head turn true; i.e. does the hole in the top of the head rotate about it's center, or does it orbit/wobble around? If yes, then either the main shaft is bent, or the head is not running true on the main shaft.
If the vibration occurs w. the blades on and goes away when they're off, then:
1) are the blades tracking well?
2) if the tracking changes as pitch is increased, then the spindle/head axle may be bent.
Another thing that helps is to consider the frequency of the vibration:
1) low frequency that affects the whole heli is most likely the main rotor head (mainshaft, flybar, etc)
2) medium frequency is usually the tail rotor (this will cause the tail to vibrate up and down at a high frequency)
3) high frequency is usually the motor and its components (e.g. fan, clutch, etc.) ( this will usually cause the fins to buzz at their tips)
Any additional information about thing's you've tried would always be helpful...
Good luck,
SteveR