RE: Gyro, Tail Motor Question
Remember that a rate gyro will only stop the rotation, not correct it. A hh gyro is needed to pull the tail back to original orientation.
Your bird doesn't sound old enough for tail motor failure to be a problem.
Some gyros need to be set to reverse. Check the instructions for the gyro and the gyro settings.
Try increasing gain until you get a response, then trim gain to liminate tail wag.
Good luck
Splat