- Joined
- Jul 1, 2019
- Messages
- 113
Hi all,
I'm currently trying to diagnose a charging problem that's been made apparent by conking out in the dark at 8pm the other night! Fortunately I was only 1/2 mile from home so did the last bit without lights.
As the ride went on she started to run rough, I have Boyer Bransden electronic ignition & a BB Power Box, which I know don't like a weak spark, so I knew something was amiss.
I also spotted that my charging light goes out instantly when I kick her over. I've got a SparkBright battery monitor on its way which will tell me a bit more.
I realised that I'd doubled up on zener diodes as I'd connected the one on the z-plate. The Power Box has one built in, so I've removed the original one but left the earth there. I don't think it would've done any harm but it's ruled it out.
Battery is an Exide AGM YT12A-BS 12V 9.5Ah. Not the foggiest when it was bought & fitted.
I've done a few (limited with my knowledge) tests this morning & this is what I found.
- Battery just off trickle charge: 13.54V
- Idle/no ancillaries: 12.82V
- ~3KRPM/no ancillaries: 12.10V
- ~3KRPM/ancillaries: 12.10V
- There's continuity between the alternator leads
- At ~3kRPM there's 34VAC from the alternator (measured between 1 lead & yellow to the Power Box)
I'm currently trying to diagnose a charging problem that's been made apparent by conking out in the dark at 8pm the other night! Fortunately I was only 1/2 mile from home so did the last bit without lights.
As the ride went on she started to run rough, I have Boyer Bransden electronic ignition & a BB Power Box, which I know don't like a weak spark, so I knew something was amiss.
I also spotted that my charging light goes out instantly when I kick her over. I've got a SparkBright battery monitor on its way which will tell me a bit more.
I realised that I'd doubled up on zener diodes as I'd connected the one on the z-plate. The Power Box has one built in, so I've removed the original one but left the earth there. I don't think it would've done any harm but it's ruled it out.
Battery is an Exide AGM YT12A-BS 12V 9.5Ah. Not the foggiest when it was bought & fitted.
I've done a few (limited with my knowledge) tests this morning & this is what I found.
- Battery just off trickle charge: 13.54V
- Idle/no ancillaries: 12.82V
- ~3KRPM/no ancillaries: 12.10V
- ~3KRPM/ancillaries: 12.10V
- There's continuity between the alternator leads
- At ~3kRPM there's 34VAC from the alternator (measured between 1 lead & yellow to the Power Box)
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