This just began this afternoon....Generator light not on when it supposed to be, with key on and also at idle. When home, I pulled the cluster and checked out the idiot light. Thought I had found the culprit with oxidized tabs on the bulb. Cleaned same and reinstalled to no avail. Volt meter does not read any volt gain beyond 12.30 on battery terminals when the engine is revved. Maybe the regulator?
Thanks
1984 electrical issue
- Airbear
- Posts: 2890
- Joined: Tue Aug 03, 2010 10:02 am
- Location: Oz, lower right hand side, in a bit, just over the lumpy part.
Re: 1984 electrical issue
Randy, it seems we don't have any electrical guru types here anymore but the UK site "BM Bikes and BM Riders" does - particularly a member called Galactic Greyhound (aka Ced). He likes nothing more than being bothered by a juicy electrical problem. See this thread - it's about a 1984 R80:
http://www.bmbikes.org.uk/Forum/viewtop ... 15&t=22297
Scroll down and check out his fault finding list. It is well worth saving for future reference.
http://www.bmbikes.org.uk/Forum/viewtop ... 15&t=22297
Scroll down and check out his fault finding list. It is well worth saving for future reference.
Charlie
and Brunhilde - 1974 R90/6

Graduate, Wallace and Gromit School of Engineering and Design (Pending)
and Brunhilde - 1974 R90/6
Graduate, Wallace and Gromit School of Engineering and Design (Pending)
-
dwerbil
- Moderator
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- Joined: Tue Aug 03, 2010 10:58 am
- Location: Round Rock, Texas
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Re: 1984 electrical issue
Thanks Airbear, but I got the sucker solved. It was the idiot light circuit board tabs that needed a bit of help. I had earlier cleaned them a bit along with the bulbs. But the generator bulb tab surface on one side was pitted a fair amount. I used a bit of aluminum foil folded several times then tucked under and over the circuit board bulb tab to beef it up a bit. With the bulb back in place it was now getting continuity through the bulb via the wiring loom pins. Got that?
Just put it all back together and on the bike. The generator idiot light shines brightly now.
Guess the instrument cluster circuit board is on its way out, and they're no longer available. Will have to go the used market sometime.
Over and out.
Just put it all back together and on the bike. The generator idiot light shines brightly now.
Guess the instrument cluster circuit board is on its way out, and they're no longer available. Will have to go the used market sometime.
Over and out.
- Airbear
- Posts: 2890
- Joined: Tue Aug 03, 2010 10:02 am
- Location: Oz, lower right hand side, in a bit, just over the lumpy part.
Re: 1984 electrical issue
Well done. If you can't find a good used circuit 'board' I suggest getting some thin sheet brass from a hobby store and soldering new tabs in.
Charlie
and Brunhilde - 1974 R90/6

Graduate, Wallace and Gromit School of Engineering and Design (Pending)
and Brunhilde - 1974 R90/6
Graduate, Wallace and Gromit School of Engineering and Design (Pending)
-
dwerbil
- Moderator
- Posts: 2883
- Joined: Tue Aug 03, 2010 10:58 am
- Location: Round Rock, Texas
- Contact:
Re: 1984 electrical issue
Great idea, Charlie. I'll keep my eyes peeled.
