I have a Saito 45 in a trainer the motor is old but still new (sat in the box) I have had the problem that after my last flight which resulted in an altercation with the ground. Anyway the results is that the motor was harder to turn over. I removed the back plale ,the moment the screws were loose the binding was eased. I removed a very slight amount off the inside of the back plate and replaced it all is fine now. Has any body had this problem with saito's