Thank you for the clear explanation. Ive got something a little more complex going on I can't seem to figure out. I have one of those Motogadget M-unit blue wired into my bike and the feed wire for the field excited regulator comes out of an auxiliary port in the m-unit. There seems to be a difference between the battery voltage and the auxiliary voltage. When I turn the power on to the bike the battery voltage will drop to around 10v and unplugging the reg/rec brings the voltage back to battery voltage. Not sure what's happening there.
Yeah, that's a pretty big drop. You normally just see about a half a volt or less drop just from energizing the alt rotor. Don't mean to insult you, but first think I'd do is try a known good battery. First find out if there's actually an M-unit problem or a power problem. One's easy to fix. The other? Well, I'm clueless on M-units. Wish I was more helpful.... sorry.
Thank you for the clear explanation. Ive got something a little more complex going on I can't seem to figure out. I have one of those Motogadget M-unit blue wired into my bike and the feed wire for the field excited regulator comes out of an auxiliary port in the m-unit. There seems to be a difference between the battery voltage and the auxiliary voltage. When I turn the power on to the bike the battery voltage will drop to around 10v and unplugging the reg/rec brings the voltage back to battery voltage. Not sure what's happening there.
Yeah, that's a pretty big drop. You normally just see about a half a volt or less drop just from energizing the alt rotor. Don't mean to insult you, but first think I'd do is try a known good battery. First find out if there's actually an M-unit problem or a power problem. One's easy to fix. The other? Well, I'm clueless on M-units. Wish I was more helpful.... sorry.
Thank you Jim, very good explanation. Just what I needed to trouble shoot my 1980 model.
Good
Care to take a look at my bike? 😆