Battery not charging

Discussion in 'Touring Models' started by cosmo56, Aug 22, 2011.

  1. cosmo56

    cosmo56 Member

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    2000 roadking, injected, 104 k miles.

    Found my battery not charging. Battery takes a charge from battery charger and holds the charge. Checked the voltage at the battery while bike running, it reads whatever the battery charge is. No change when revving the bike up. Thought stator was bad. Checked ac output from stator. Ac volts goes from about 8-9 volts at low idle to 40- 50 volts at 2000- 3000 rpm. Checked for shorts or opens on stator. Checks ok. Must be the regulator. Replaced the regulator. Same readings, battery still not charging. Checked the stator output again. Still appears to be working. Spoke to Bubbie by phone and he told me that Hoople might have some suggestions.
     
  2. glider

    glider Veteran Member

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    The stator sounds like it's alright but sometimes they can give a false reading too.

    Have you checked the lead from the regulator to the battery to see if there is any brakes in it and that continuity is there?

    Here's a flow chart to test the system out again...

    Harley Davidson Community
     
    Last edited: Aug 22, 2011
  3. btsom

    btsom Active Member

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    Can't match Hoople's knowledge, but for the moment, I'd check continuity on the output side of the regulator. Check each wire for open somewhere along its length. Also, had anything else electrical apart recently? Any connectors unplugged that might not have gone all the way back together? Any components R & R'ed that might now might be pinching a wire?
     
  4. cosmo56

    cosmo56 Member

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    the leads are new from the regulator to the battery. Also can't find any shorts anywhere else. No work done. Rode the bike home at night. Next day battery was dead. I did think that my lights were a bit dim on the ride home.
     
    Last edited: Aug 22, 2011
  5. glider

    glider Veteran Member

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    I posted this above, may help...

    Harley Davidson Community
     
  6. Hoople

    Hoople Account Removed

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    Checking the output of the stator without a load attached can be misleading. That 8-9 volts sounds way too low at idle. It should be more like 20. I would say the problem is under the primary cover. I would bet as soon as you put a load on the stator that 40 volts you see would fall flat.

    Don't know if you want to try it, but I would hook up the stator to the regulator then pierce each stator wire with a pin in order to measure the voltage while the stator connector is hooked up. See if you get that 40 volt reading with the stator hooked to the regulator with the engine running.

    Don't let the pins short to each other.:)
     
  7. cosmo56

    cosmo56 Member

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    Thanks, I will give that a try. Worse case scenario I will replace the stator.
     
  8. R. Lewis

    R. Lewis Senior Member Retired Moderators

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    just asking ---- how old is the battery?
     
  9. cosmo56

    cosmo56 Member

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    2 years old next month. The battery charges fine on a charger and holds a charge out of the bike and connected to the bike.
     
  10. CalgaryBikeBum

    CalgaryBikeBum Active Member

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    Also. Did you notice any new vibrations in the days leading up to it failing? I had been riding my 2000 Roadking and suddenly noticed a new vibration? A few days later I rode it out of town and shut it off. Came out. Battery Dead. In my case once I stripped it down I found the Rotor magnets had slid around (guess I shouldn't ride it so hard) and they were all on one side of Rotor (thus the vibration) and so I would get a bit of charging, then nothing. Etc etc. Just another thing to check if you have it apart.