Thats har to tell without looking at it, if you are running with tight blades you will have to sett them in the correct position befor spinning up, and spinn it up somewhat gently, pulle the blades by the same point on the tips. if you are running with the blades loose, make very sure nothing on you heli is wobling or shaking around as it can ofsett the bladepostion and cause the major deathwobble. All in all the more accratly your entire heli is balanced the less chanse it is to develop the deathwobble in flight.