Well for some reason when I start my nexus, after a few seconds of trying the starter shaft locks, when I checked I noticed the black piece (I believe to be the clutch, circle disc with fins) that is attached to the engine moves off the spindle 1/4" outward, so I tighten the nut back up which holds it in place, put it all together and the same thing all over again, has anyone heard of this problem, I'm pretty much at a stand still trying to figure this one out, oh and this is a new heli, never flown and going through the break in process with the motor.