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Goldstar 350 battery failure

Posted By: Bill Harrison

Goldstar 350 battery failure - 08/10/18 3:01 pm

I'm sorting out a 350 Goldie, still not got the charging circuit sorted but I've had 2 battery failures. Could the vibration be the problem? Both batteries were standard lead acid ones, the same as the original, the old one still works OK ish but the new ones lost a cell after about 10 miles (4.3 volts and no charge). Suggestions very welcome!
Posted By: BSA_WM20

Re: Goldstar 350 battery failure - 08/11/18 11:41 am

They were not the same as the original.
It had Pb-Sb plates that were 2.5mm
Modern battey will have Pb-Ca plates that are 0.75mm thick.
You will have to go with a sealed battery with AGM or it Cyclons that are spiral wound so mechanically indestructible.
Posted By: bodine031

Re: Goldstar 350 battery failure - 08/11/18 2:17 pm

My Victor has a Gel Electrolite battery going on three years. Longest I ever got on a sealed AGM was 8 months. I believe my issue was vibration
Brand is a Bike Master from Tucker Rocky (5L group size)
Posted By: Bill Harrison

Re: Goldstar 350 battery failure - 08/11/18 6:54 pm

I'll keep the original then and swap to Gel when required. I'll use the new one I eventually get as a replacement in another machine!
Posted By: koan58

Re: Goldstar 350 battery failure - 08/11/18 8:24 pm

Vibration is a killer for batteries, but a charging system that's not "sorted" is just as damaging.

Don't waste more money on batteries till the dynamo/regulator is working properly.

Most ordinary batteries can give fair service as long as they're not flapping about and kept fully charged (not boiled).
Posted By: Bill Harrison

Re: Goldstar 350 battery failure - 09/14/18 7:58 am

Originally Posted by koan58
Vibration is a killer for batteries, but a charging system that's not "sorted" is just as damaging.

Don't waste more money on batteries till the dynamo/regulator is working properly.

Most ordinary batteries can give fair service as long as they're not flapping about and kept fully charged (not boiled).

Charging system is OK. I've cleaned up the dynamo, new brushes and fibre drive wheel, checked on the bench and motors correctly, new solid state Voltage regulator-checked with a new meter! Voltage rises to about 6.8 on the bike although no great +ve charge on ammeter unless you leave the lights on a while then 2-3 amp charge for a couple of minutes. I think vibration is the issue.
Posted By: Andy Higham

Re: Goldstar 350 battery failure - 09/14/18 9:39 am

Have the batteries failed or are they just flat due to dynamo not charging?
Posted By: Andy Higham

Re: Goldstar 350 battery failure - 09/14/18 10:12 am

6.8v is very low, it should be around 7.2
Posted By: BSA_WM20

Re: Goldstar 350 battery failure - 09/14/18 2:12 pm

Originally Posted by Bill Harrison
I'm sorting out a 350 Goldie, still not got the charging circuit sorted but I've had 2 battery failures. Could the vibration be the problem? Both batteries were standard lead acid ones, the same as the original, the old one still works OK ish but the new ones lost a cell after about 10 miles (4.3 volts and no charge). Suggestions very welcome!


Yes.
When I started at Simsmetal in the 70's battery grids were 2mm to 3 mm .
When I left 4 years latter they were 0.5mm thick.

Back when I was living with my parents a heavy duty 13 plate battery was a 2 man lift, now days I can carry 2 of them comfortably and I am nowhere near as strong now as I was then.

So mechanical damage is high particularly on our shakey old bikes.

By far the best type of battery are the PVR AGM type
Pressure Valve Regulated prevents them from gassing
Adsorbent Glass Mat supports the grid plates while allowing free flow of ions in the electrolyte.

And from a mechanical point of view the spiral cell batteries are streets ahead.

For bikes like yours that run magneto ignition you can also get away with with a gell cell because unless you are a real horn jockey or like to melt the bitumen with 10kW of intense white light, the amperage demands on the battery are quite modest.
Posted By: Bill Harrison

Re: Goldstar 350 battery failure - 10/24/18 11:46 am

Thanks for the help
I'm on coil ignition so need the battery. Have installed an agm battery, quite small, packed in foam in old style battery box
All good now apart from losing the odd but and bolt!
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