Help me with this one. I recently crashed my TREX 450SE, and it was a bad one. My rear cyclic servo - an HB-65 - crapped out and the darn heli almost hit me. I had to run from it and because of that and shock in general I didn't hit the motor cut. I was in idle-up and so the heli kind of paused for a second and then started doing the "chicken dance" and stripped the main gear. So I figure that for a second it was pulling some hefty amps.

I have finally finished rebuilding and changed the bad servo and put in metal gears in all 3 cyclic servos. Yesterday when I was powering up the motor seemed to loose power and I was unable to take off. Then all of the sudden full power went to the motor and it stripped another main gear. After that it behaved normally, but I just can't trust it.

The motor is a Hacker A20-6xl and the ESC is an Align 35A. Is there any way to test whether it is the motor or ESC? My inclination is to replace the ESC, but I'd like to know for sure. Also, what would be a good ESC to use?

Well, if you don't feel safe with that speed control (and I think that's wise), I would pick up a new ESC. Then fly the heli for some while and just see what happens. I would believe you are correct in pointing first at the speed control. Those brushless motors are fairly tough and are built to take whatever that ESC dishes out. Good luck either way!

Just my $.02
- Chaz