Engine should move in the rotational axis about the prop shaft.

If you are getting the spinner moving around then your nose ring is not properly installed or is loose.

The nose ring captures the front bearing of the engine case and keeps it inline. The head of the motor will move a bit maybe 3/8" or more when at idle but once rpms increase it smooths right out and stays pretty still absorbing the high frequency stuff The shake and shimmy at idle is a low frequency vibration and won't hurt your model like the high frequency vibes will.


Allen