The saga continues...
I installed a 10 amp BEC and my back-up ESC. Put it on the track and could only run about 10% throttle w/o a significant shutter. Shutter continued between 10 and 20% throttle. 20% and up it went dead.
Hall effect sensor test checked out ok. Did notice some burnt insulation on my sensor cable, undoubtedly from the last ESC burning up.
So... Is it just the sensor cable being damaged having issues at higher power levels or did my last ESC take my motor with it?