panhead battery driving me nuts!

Electrical issues
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panhead battery driving me nuts!


Post by 1958ken » Sun Jan 15, 2012 1:42 am

This topic has probably been discussed to death but a any help from the group would be apprieciated.I'm running the alternator conversion (J P cycles) on my 58 pan.I have a Cycle Electrics "L" series regulator because of the battery location in the horseshoe oil tank. I'm getting good voltages when I rev the bike,between 13v-14v dc,I also have bright lights when the bike is running. After riding a few miles the battery drops down to around 11.5v.
I'm running a cheapo Chinese made sealed battery and I think this my be the problem. Thanks for any input and Happy New Year,guys.

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Re: panhead battery driving me nuts!


Post by Chopper mIke » Sun Jan 15, 2012 4:15 am

12v system? if it is try a Deka ETX9 i have had great luck with these.

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Re: panhead battery driving me nuts!


Post by CaptMike » Sun Jan 15, 2012 4:28 am

Chopper mIke wrote:12v system? if it is try a Deka ETX9 i have had great luck with these.
I ordered an ES12-12 Battery it's a 12 Volt 12 ah. It fits in the battery box with some space around it and clamped down nicely.

Are you running an Idiot Light? You might possibly have a bad battery but I think you're not charging. You said you're running an Alternator (not a generator), once it's charging it should continue to put out voltage. How did you wire the setup?

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Re: panhead battery driving me nuts!


Post by Hog54 » Sun Jan 15, 2012 4:14 pm

Do either one of those batterys fit in a stock oil tank?They look like electric start batterys to me?

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Re: panhead battery driving me nuts!


Post by Hauula Pan » Sun Jan 15, 2012 6:56 pm

2 possible problems, 1 your battery could be bad or going bad & is possibly taking a surface charge that reads as the 13 to 14 volts you see but under load its really only got 11 to 11.5, 2nd possibility is your regulator isn't working properly & as you run the bike you're drawing more from the battery than you're putting in. Fully charge the battery & load test it. If it checks out good then test your regulator & stator. (Note) The old test for checking Generators by unhooking your battery will destroy an Alternator so don't try that. I still don't get it - all these 12 volt conversions, with nothing but problems... nothing wrong with the original & simple 6 volt system. (Well as long as the relay doesn't stick anyway.)

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Re: panhead battery driving me nuts!


Post by Cotten » Sun Jan 15, 2012 10:03 pm

Whoa now Haaula Pan!

Not all 12v conversions use flying saucer parts like an alternator.

It can even be achieved with 0EM parts, except for the battery wild card.

My question for 1958Ken is if the catalog alternator kit called for a generator regulator, one of CE's late-model low-voltage alternator regualtors, or no additional regulation at all?


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