Tail motor, trim, or other issue?

[Mooncatt]

I've noticed that my tail motor tends to get stronger, or the trim is being skewed during flight. I can start with a fresh battery and have rudder trim almost all the way left (clockwise) while doing tail in hovering and at the end of a 6 minute hover practice, I will have moved the trim center or a little past in the other direction to hold heading. Once the trim is set, it'll maintain the heading for a little bit, but then start to slowly yaw clockwise. Give it a couple clicks trim to counter, and it'll be ok for a little while again before drifting. Any idea if it's the motor acting up, the trim getting out of whack in the electronics or what? I figured if the motor started "loosing up" when warm or whatever to let it work more efficiently, the gyro would offset it by reducing power to it some.

It's been doing this since brand new and haven't been able to get much past basic manuevers in practice because I'm constantly having to adjust the trim and loose a bit of control when I do so. It's taken a few crashes before I got hovering down, but nothing too serious I wouldn't think. I was fortunate to be in a padded area, so there was no solid object strikes.

[Pfloyd]

What radio are you using?

[Mooncatt]

The included radio and happens on both high and low rates. I don't have a stand alone radio to bind with it for testing.

[sooners]

you said you have crashed a few times check your tail rotor and make sure its not bent out of whack. Also check main rotors and fly bar make sure flybar isn't bent in any way. I have never had to trim my msr and I have 2 of them. Just using stock transmitter with them also. But have replaced tail motors on both. I could tell when my tail motors got bad because of handling for one and they whined pretty good. The tail would make sudden jerking motions also.