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electrical issues

Electrical issues
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electrical issues


Post by jay51 » Wed Jul 01, 2009 11:06 pm

I keep cooking my battery on my 51 pan chopper, I have replaced the mechanical voltage regulator with a new one and had my generator bench tested, and I am still sending 10 to 22 volts to my battery. I was talking with an old mechanic today who said the problem is that my 12 volt generator is over charging the small battery I have in my old horseshoe oil bag (which held a 6 volt battery originally). He said that I can replace my oilbag, purchace a low charging generator or I might be able to put a capicitor on it. Has any one else had this issue and how did you resolve it.

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Re: electrical issues


Post by FlatHeadSix » Thu Jul 02, 2009 4:39 am

If you are cooking your battery, overcharging it, boiling it out, then your regulator is NOT regulating. A good regulator does not care what size the capacity of the battery is or where it is located, if the battery has a full charge the regulator should sense that and reduce the amount of charge it tries to put in it. You may want to try another regulator.


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Re: electrical issues


Post by jay51 » Thu Jul 02, 2009 10:51 am

I already replaced it with both a mechanical and a solid state regulator and the problem does not change, I even ran individual grounds from the regulator and generator back to the battery, I also picked up a second generator and had it bench tested and tried it, still the same over charging issue. The only change came when I installed the solid state regulator the volts would stop at 16 VDC at higher RPMs instead of going into the 20's.

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Re: electrical issues


Post by john HD » Thu Jul 02, 2009 11:43 am

sounds like the field is grounded on your generator -or- the field resistor on the regulator is of the wrong value. could you have installed an automotive regulator by mistake?


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Re: electrical issues


Post by ozwick86 » Thu Jul 02, 2009 3:49 pm

Have you checked your battery? Might try another one could have a short in it?

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Re: electrical issues


Post by jay51 » Fri Jul 03, 2009 1:14 am

I have tried 2 different generators, the mechanical regulator is what v-twin and J&P have, the electronic regulator is off my dads brand new generator (came as a unit), I guess I will install dads generator and regulator and see if this makes a difference, this is my third battery, I have grounded everything directly to the battery as well. The electronic regulator has been the best only sending 15.95 VDC to the battery at higher RPMs I am also going to check my Fluke meter to my two other meters in my work van incase my meter is off a VDC or two.

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Re: electrical issues


Post by RussW » Fri Jul 03, 2009 2:18 am

Cycle Electric makes voltage regulators specifically designed to not overcharge small A/H batteries mounted in a stock horseshoe oil tank. They can either be purchased separately or as part of a low-charging Generator-end mount regulator kit.
Check out part #'s CE-102L and CE-540L.

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Re: electrical issues


Post by ozwick86 » Fri Jul 03, 2009 3:02 am

I run the cycle electric end mounted generator "low output" regulator on my 59.

What brand of battery are you purchasing? I run the Yuasa YTZ14S. Tip it on it's end with a couple blocks of wood. GREAT BATTERY! Your battery could be your problem since you say you have gone through 3 of them so far??

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Re: electrical issues


Post by Frankenstein » Sun Jul 05, 2009 1:56 pm

couple of questions to help clarify the situation.
How long is it taking to fry your battery? A week, month, a season?
Are you having trouble blowing light bulbs?
Where are you taking your voltage readings? Across the battery terminals, from plus terminal to a chassis ground, right at the generator output terminal?
I'm trying to determine if we have two issues. How you're reading the voltage, and a battery that's being killed.
A battery that sees 20+ volts all the time might last a month,lamps won't last long, and the generator is probably going to die also.
As you haven't complained of lamp and generator issues, I'm suspicous.
A battery that takes a couple of months to die, no light problems, may just be suffering from the small battery blues, can't handle normal charging rate for a full size battery. And the voltage readings are faulty due to othe issues.
Starting with the latest findings, lets go from there.
The only voltage readings I'd trust at this point are with your Dad's electronic unit, taken at either the output lead from the regulator, or the armature terminal of the generator, grounding the meter firmly at the generator shell. The readings you got with that regulator, at 15.95 sounds reasonable for a reading taken directly at the armature post on the generator. Is that where you connected for that reading? Also, the voltage reading should be fairly constant, from fast idle to top speed.
So, I'm suggesting double checking your readings at that generator and regulator output. The regulator output is going to be lower than the armature terminal, by the way, from .3 to 1.2 or so lower, according to the amperage output being drawn. It's the drop across the reverse current diode in the regulator. (Doing the same job as the "solid state" cutout).
You may even want to disconnect the regulator output wire so it's disconnected from the bike wiring and verify that the regulator is giving a solid output, stand alone.

If ultimately, wiring, etc all check o.k, and the issue is standard voltage and small battery, a cheap rectifier diode in series with the generator output may drop the output enough to keep the battery happy.
Make some checks and we'll see what to do next,

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Re: electrical issues


Post by duoglide58 » Fri Jul 17, 2009 4:16 am

I had the same problems frying the small batteries and going through regulators. Those went away when I went to the Cycle Electric generator and low out put integrated regulator.

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