Charging system is killing me.

[Emarcottesr]

1979 CB750L the second the brushes make contact with the rotor the battery immediately drops by a few volts and continues to decline the brushes themselves start getting extremely hot to the point of smoking. This is with just the ignition on bike not even running. The coils are brand new and wired in correctly. When I got the bike one of the brushes was stuck and not making contact with the rotor a when I freed it that’s when I found this whole issue. So far as I can tell so far everything checks out as good on the multimeter I don’t know what is going on here.

 

[Emarcottesr]

Unhooked the white wire on that goes to the second brush that touches the rotor now it works fine. WTF….

 

[brettp]

Sounds like that wire is your issue!

 

[Emarcottesr]

It should need that wire. It’s supposed to be necessary but apparently it’s not cause now it’s charging fine and running better than ever. Hit 105mph last night without any issue