Discharging battery

[bsaketcase650]

It's seems only a shortwhile ago that I was crowing about a successful rebuild and enjoying getting a few miles on the clock. As is so often the case these things come to bite you in the rear end! I seem to have an electrical problem and being an electrickery ignornamus  I am struggling to resolve it. Firstly, the ammeter is no longer showing any signs of life except for indicating a discharge when lights are switched on or horn used. No sign of a positive reading irrespective of engine speed. I now find that within a very short time the battery appears incapable of powering anything. Having removed it this morning and charging it (reading 6.22v across the terminals prior to refitting) I have refitted it. On switching on the lights and sounding the horn power was back. Start the engine - no reading on the ammeter. Stop engine, switch lights on and can see them fading before my eyes!! The battery is a new Varta 6v bought only a month ago. What's happening here. I have tested the dynamo by connecting the two terminals together and connecting a voltmeter through to earth. Shows a rising voltage with increased engine speed.  Incidentally, the dynamo has been freshly refurbished by a well known specialist and is matched to one of manor mike's regulators . All was working fine until this recent development. Where's the power going to and why isn't the ammeter giving any positive reading?
Any ideas fellas?

Regards
Simon

[Pollock]

It sounds like you have a weak cell which means shorting of a cell in your battery. Similiar to a car that will run fine, and start fine. But leave the lights on for 1 minute and the solinoid clicks.  This is coming from an X battery salesman.  Cycle batteries don't have much deep cell capabilities. With that said it shouldn't dim before your eyes.  I don't have a shematic in front of me but yes when the engine is running the amp meter should show it jumping with the rpm's..and if you have it idle low enough a draw on the amps.
Pollock

[bsa-bill]

Hi Simon - My mate just had the exactly the same symptoms with a refurbished dynamo

Although the dynamo is showing a charge is it correct polarity ( not unknown for refurbished dynamo to be wrong polarity )
Simple way to find out and cure is to "Flash" the dynamo as described somewhere in the Forum archives. this corrects the battery polarity.

Of course this is elecrtics so could be way off the mark with many other causes (  is the smoke escaping  )

All the best - Bill

[trevinoz]

Simon
        Try connecting your voltmeter across the battery with the engine running.
If there is no increase in voltage at the terminals, as your generator appears to be ok and your polarity is hopefully correct, the next thing to do is check your circuits are intact and have a look at your regulator.
Trev.

[Dynamo Regulators Mike]

Simon
If you can't get to the bottom of your lack of charge return the regulator to me and I will check it out, FOC of course.
To eliminate other possible issues with wiring or battery you can run the dynamo D & F leads direct to the regulator, earth the regulator and measure the voltage output with nothing else connected.
Mike

[bsaketcase650]

Thanks for the advice guys. Still no positive indication on the ammeter! I checked the polarity on the dynamo and flashed it just to make sure it remains at + earth. Battery now appears to be holding a charge in the short term, but without any input from the dynamo  that clearly will not last for long. I will run Mike's test and see what that reveals (thanks for the offer to check the regulator - obviously if I have "fried" it I will order another).

Regards to all

Simon