Can't go over 2500 rpm's?

[tsubaki]

I don't understand how this problem presented itself without some prompting.
Did any wires somehow get arced, grounded or shorted? Normally that would damage a powerpack.
If it was the magnets shifting in the flywheel it wouldn't run or at best run like crap.
Whatever it is, at least it happened in the yard and not offshore.
Look at it that way.