Bad Battery Or?

[torch]

With the engine running, measure the voltage between each pairing of the white wires on the harness side.

Actually, this is another good place to use a clamp-on ammeter -- this time with the connectors plugged in and looking for AC current, of course.

Attached is a nice article with pictures explaining the use of an oscilloscope to diagnose the charging system better than I did.

 

[RedRiderMN]

@K-Flyer

When I had a set of Motolites on my BMW, I replaced the incandescent bulbs with some LED bulbs. This significantly reduced the drain
on the electrical system.

https://motolight.com/product/super-bright-led-motolights/



Their website does NOT list the wattage for the LED bulbs, however.

 

[Rocnsanman]

Bike has over 65k miles. Problem just appeared a few weeks ago. I'm also surprised that battery discharges at 13.8. I'll try some of the other suggestions. But winter is coming and I think I will ride without the moto lights until I can get to checking it out. Wish I could find a mechanic in the area that I could trust. I have too many problems with back and knees to do much myself. Picture is of me at least 25 years ago. I've worn out somewhat since then.

Haven't we all ........