Resolved problem, thank you Seymore
seymore;56982 said:
What type battery are you using?
Does e-start sound normal or slow?
Have you tried replacing the battery?
Did you check all the battery cable connections on both end?
A battery with a bad or intermittent cell or connection could cause the problem even though the data log shows normal voltage. The effect from the high current draw during starting might cause a unusual voltage fluctuation that could confuse the ECU.
Just some wild guesses to your odd riddle.
Seymore, thank you for causing me to think about the battery again. I had replaced the battery with a spare and then the new LiFePO4 early on in my troubleshooting last month or the month before and found neither made any difference.
I figured in for a penny in for pound, I might as well try a 4th battery, the one from my buddies donor cycle, since I've just about run out of parts to swap!
What do you know, I'm unable to reproduce the problem. I rode and stopped and started the engine using the estart 15 times, no problems.
My mistake was assuming two things, that my spare and my newly built LiFePO4 were good or still good, particularly the LiFePO4 tested very well under load when new but since the problem remained, I swapped back to my spare and when this didn't fix the problem I went back to the LIfePO4 battery. Well now the LifePO4 battery sags horribly, down to 9V, under load, it seems to spin the motor just as fast as my spare, but certainly not as fast as my buddy's battery.
The low voltage sag caused by the starter motor must have been just below the tolerance for the ECU when it acquired the signal from all the sensors, screwing everything up.
When bump started the sag does not occur of course, hence all is well.
I will buy a new battery! I also reconnected the PC V + AT and they are functioning normally too.
I don't believe there is any need to swap the flywheel now, I was struggling to believe that could be the problem but I had thought I had run out of options. I certainly know the bike a bunch better than when this all started. Thanks for all the ideas along the way.
And everyone should note, the HT coil should measure 20k ohms, not 5k ohms like the service manual states.