"Check voltage at battery, sho
"Check voltage at battery, should increase from 12 to 14 or more while charging.
(More charged the battery, the higher the voltage, not much "Regulation".)
Charging system has an inline fuse near the output plug and manual calls for output to increase as high as 5 Amp at 6,000 RPM.
Leads from Charging Coil should have a resistance of 0.12~0.15 Ohms between them.
Diode/Rectifier should show continuity from blue to green and red to blue but not from green to blue or blue to red.
___________________________________________
This would be very non-standard, but my old BF100 Never lit its 'oil-pressure' light, so I fitted (soldered) a tiny Sylvania '37 BP' 14 Volt Lamp inside receptical and still no lighting.
Then I removed the connection from the CDI box (to OP bulb) and connected it to the (+) Charging Lead, now I have Oil Pressure and Charging confirmation from same light
"
