earlwb

I suspect the loose motor screws has something to do with the heli-frame where the motor is mounted. The plastic tends to flow slightly away from the screw pressure, plus the motor gets hot and that may soften the plastic too. So it is wise to give the motor screws a check from time to time. To avoid overtightening the screws, you should loosen and then retighten them. Do one screw at a time so the motor gear spacing remains the same.

I don't know yet what to think about the tail rotor gears. Maybe some heli's have a gear or gears that are too tight or maybe a bad bearing causing excess drag with the gears.