You could possibly use a small crescent wrench on the top of the motor in between the slots. You don't want to use pliers or vice grips to hold the motor body..

Cut a strip of boot leather (If Available)  long enough to wrap all of the way around the motor.     Make it about 1/2"  wide.   use that new length of leather to protect the motor.   wrap it around the motor.   Using a pair of pliers,applying pressure to the leather, not directly to the metal of the motor,hold the motor in place while removing prop with hand.    Only use enough pressure to hold the motor still.      Do not squeeze hard enough to misshape the motor bell. Hope that helps.

Michael Starley Posted at 2015-5-22 08:31
Cut a strip of boot leather (If Available)  long enough to wrap all of the way around the motor.     ...

Why are they so tight? The only time i couldnt get mine off was when it crashed. just grip the motor with your fingers  and turn.

Firnware issue.