electrical problems, HELP........

Problem, Battery appears not to be charging while riding.
Have been having battery problems for a while now, so here is a bit of history and steps taken.

Fitted new battery and regulator/rectifer this time last year. Keep battery charged on battery tender. Battry a bit iffy last few weeks, so fitted another new one a few days before the following.
Went for long ride last Sunday. After approx 35 out miles stoped for people to catch up, bike would not start. Just about got home. Checked voltage while bike was running to see if reg working ok, only charging at about 11/12v and not the 13+ odd it shoud be., switched off and checked battery, about 8.5v. Left bike for hour or so and voltage increased back to about 10. Bike still not starting.
Fitted old battery, bike started first go and charging a 13+ volts!!!!!!!!
Left bike for a week until yesterday not on charge or anything and still with old battery in it. Started first go. Went to local auto electrician. He checked what he could and could not find anything wrong, no shorts, no drain and charge rate fine.
Went for short run, came back, battery down to about 12v and charging only at 12.6v. What the hell. Regulator faulty????? Fitted new one, no change.
At a lost now, where to next?
Is it possibly the stator, do they pack up and if so how? Suddenly or bit by bit. Would it be the stator or magnets falling off rotor??

Any help, suggestions, advice etc most welcome.
Hope to go to European HOG rally in Killarney in two weeks, so not much time.

Sorry if question a bit long winded.
Cheers
T C

[ian]

Check the earth lead from the battery to frame for good contact had same problem with a Buell took me a long time to find it.

[Phil]

Year, model?

[davy-b]

If you have a chrome battery cover check to make sure it hasn't chaffed the live lead.

[Hawkeye]

Taken from the workshop manual for 1986 to 1990 Sportsters.

Disconnect the regulator/rectifier and connect an AC voltmeter across the stator sockets (the lead that comes FROM the altenator).
The altenator should produce 12 - 18 AC volts per 1000 engine rpm.


I personally don't think this is your fault, it sounds more like a broken/worn through wire. Always good the check the earth side of things, dont think it 'looks good', take it off give it a tug and replace making sure it's clean and not corroded.

On the + side of the batt are two wires (well there are on mine), leave the big one connected to the battery (starter solenoid lead) and put a multimeter set to amps in line. Thats between the battery and the thin wire. Switch the ignition on and the meter ot digital display will go to minus (if not swap the meter leads around. Start the engine and switch on the lights. Rev the engine up and it should charge at quite low revs.


hope this helps, if there are other figures you want give me a shout and i will look them up in the book of words

Thanks for all the help.
Took bull by horns and replaced regulator. Seems to have cured problem.
At least Accel reg have lifetime guarentee!!!!!!

Cheers
T C.

If you're in Killarney for rally at the end of the week, have a good one, maybe see you there?