My K3 had been running fine but recently I came up with an electrical problem.
1973 CB750 K3
New wiring harness, Hondaman fuse block, fresh battery kept on a battery tender.
When I turn on the ignition the dash lights are dim and it won't turn over.
I was able to jump start it and only saw 6 volts at the battery at high RPM, about 3000.
Won't idle at all, likely due to low voltage.
When shut down, the battery shows 12.4 volts connected or disconnected.
I checked the diodes in the modern regulator/rectifier, they check ok.
I checked the stator, it checks ok. No shorts to ground or each other.
I also noticed that with the ignition on and nothing else being done, the regulator rectifier sings just sitting there, it has a whine. That doesn't seem right.
Any ideas?