The rest of the story
Sorry for the late update. Here's the rest of the story.
Could not get the combination of the Kontronik Jive 80+HV and Xera 4035/3Y-400 motor to start. The motor operated fine using two other ESC's and the Jive ESC ran two other motors with no issue.
I sent both the ESC and motor to David at Xera. He was able to run the combo on the bench with no problem. He said he had spread the pins a bit which might have been the problem. (Xera tech support is the greatest. David gets back to you right away - In contrast, Kontronik has yet to responded and it's been over a week)
Got the combo back and reinstalled in my Joker II. Motor still would not start and the LED on the ESC just flashed slowly. Same as before. So...
I stretched the ESC throttle lead over to an identical receiver in a different heli. The motor ran just fine. Bad receiver?
I connected the ESC back to the original receiver and powered up. The motor started, but I noted smoke coming from the tailboom area. I had apparently jostled things a bit when running the wires between the two helis and disturbed the positioning of the Helicommand Profi which had previously made hard contact with the tailboom C/F support rod.
A quick look showed that the smoke originated from the C/F rod where it now barely touched the Profi case. I separated the two a little and tried again. This time I got a spark jumping the gap as the motor started. Wow!
I separated the Profi case from the rod by quite a bit this time and the motor ran normally. I thought about the electrical system a bit. If I didn't have the Profi with the electrical system grounded to its metal case, there would normally be no contact between the ESC/BEC and the ground of the airframe.
I ohmed out the motor leads to the mounting pad of the motor and found there was very little resistance. The motor had an internal short. I measured the same resistance in the two other motors that had run normally, and found there was no connection between the leads and the motor cases which is why they were able to operate when the Xera would not.
Had I not had the Profi, there would have been no opportunity for the shorted motor to contact the electrical system ground and the motor would have run with no issues until some piece of electrical equipment was installed that completed the circuit from the motor case to the electrical system ground.
Bottom line. a new motor will be on the way shortly, and my Profi will have a solid ground wire installed from the case to the airframe ground.
Life would have been very interesting indeed if the Profi case had not been touching ground. Everything would have been fine until a tool or something closed the gap - then sparks and smoke.
This problem is not limited to the Xera but could hapen to any motor. if you get bored, check for continuity between your motor leads and the motor case ground. You might keep yourself from having a thrill.