hey, i just found something.

quote: Bdavison's E-flite Blade Assembly, pg 16, post 398.
originally from Bdavison.
" got to fly a Blade with the "E-flite" brand bell/hiller upgrade...Hmmm. We had some issues. For some reason the heli developed this gyroscopic wobble. We reduced the pitch a little to get the headspeed up, which did improve it somewhat....but not quite perfect. So far based on what I can tell (ignoring the wobble) is that it flys good. Seems responsive just like the Esky head. I kind of prefer the E-sky head, as the setup is cleaner. I dont care much for the 45 degree angle of the linkages on the e-flite brand one. "

so might this wobble be a flaw in the bh head rather than my main shaft?