Battery holding charge

[Paul F]

I need some help with an electrical issue. I thought it was a battery problem but I installed a new battery and went on a ride today and it would not hold a charge. I had to jump start the bike several times but eventually the bike would not idle. Is this a regulator/rectifer problem?

[relic-rider]

Yup. Either that or your stator is no good. Check out the stator papers on this site, to help diagnose your problem. Or use this fault finding chart from the Electrosport site:

http://www.electrosport.com/electrosport_fault_finding.html

[Paul F]

thanks for the help. I will check out the site.

[tconroy]

thanks for the help. I will check out the site.

Its probably the stator.When my r/r started going bad it boiled the water out of the battery a little every week .

[Steve]

Its probably the stator.When my r/r started going bad it boiled the water out of the battery a little every week .

NOT NECESSARILY.

The rectifier part of the r/r has 6 diodes in it. Any one of them can open or short. Either way, output will be LESS.

The regulator part of the r/r has high-power switching transistors (not sure what kind) in it. They can fail in the open position, which will increase the voltage, or they can fail in the closed position (a dead short) which will reduce the voltage.

FOUR ways for the r/r to fail, three of them REDUCE the output.
Congratulations, you beat the odds. \\/


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[tconroy]

Thanks Steve for your answer.I hate electrical stuff and dont understand it that well but Im glad somebody does!!!!!! Im also glad I just had to replace my r/r before something bad happened.

[Paul F]

Battery not holding charge

Thanks for the info. I rode the bike home this morning. I will try to test the r/r today. What do you think is the best way to do the test?

[purplemotoman]

I'm not saying that this is your problem but do you have a chrome cover over your starter?
Once I had a similar problem and I spent about $800.00 on a new stator and a r/r box back in the day when they were expensive.
When I still had the problem, I would just kickstart it and ride with the headlight off. One day I noticed there was an orange glow on the top of my chrome starter cover.
When I pulled the cover off I discovered that my power wire for the starter was shorting out against the cover. I put a heavy duty plastic cover over the wire, taped it, put the chrome cover back on and it worked fine.
I gave my old stator and r/r box to a buddy and he put them on his bike and they worked fine.

[Steve]

I will try to test the r/r today. What do you think is the best way to do the test?

Do you have a volt/ohm meter?
Why not? :shock:
Besides wrenches and screwdrivers, it is one of the basic tools that should be in everybody's toolbox. 8-[

Here is a link to the GS Garage. Scroll down and you will see The Stator Papers. All are informative, but Volume IV has the troubleshooting process that you need.


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[Paul F]

I tested it yesterday with a volt meter. It showed no increase in voltage at 5000 rpm. Sounds like it is the r/r. I have on on order from Electrosport. 99.00.:-D

[Steve]

Personally, I think the 5,000 rpm number is over-rated. The book calls for that speed when checking stator output, so I might use it there, but checking voltage to the battery can be done by keeping rpm under 2500 or so. On both of my GSs, voltage peaks about 1500 rpm, then drops just a little as rpm rises, due to ingnition demands.


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[Paul F]

Personally, I think the 5,000 rpm number is over-rated. The book calls for that speed when checking stator output, so I might use it there, but checking voltage to the battery can be done by keeping rpm under 2500 or so. On both of my GSs, voltage peaks about 1500 rpm, then drops just a little as rpm rises, due to ingnition demands.


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Well I installed the r/r and it is showing an increase from 12/13 volts to 14 volts at 2500 rpm. It was the r/r. Thanks for all the help.