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Currently chasing an electrical gremlin - oh the joy. There are lots of threads on checking the phases of a stator with a volt meter but not a one of them I can find say exactly which notch on the meter I need to be using - 200, 2000, 20k? Higher?
 

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Use the lowest possible range for an accurate reading. If the expected reading will be under 200 ohms use that range.
 

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If the spec is .3-.5 ohms, .9 is a little high. But the error in your dmm could account for the difference. I'd look into calibrating your multimeter, not because it might wrong, bit because your lowest setting is 200. A lower setting, like 20, would make me more confident in the resistance reading I was getting.
 

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If you have to put on a battery disconnect. I have one bike I went through the starter, charging system, wiring and after fixing a short still has an issue. I just turn the knob to disconnect and it works. I figured it did it on its own maybe I'll hit a bump and it will go away. Sounds good anyway.
 

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Discussion Starter #9
R/R tested good, but they're not horribly expensive so I ordered a new one anyway. It should be in this afternoon's mail.
 

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Hope your dead battery issue is resolved.
When I was evaluating electrical issues I found that an older style analog multimeter was more accurate and readily calibrated than newer digital meters. CATC-Appliance-Tools-Analog-Multimeter.jpg
 

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Guess I would be chasing a voltage problem first... Making sure that the running voltage is above 13.8.... If it's up above 14.8 when rev'd up to <>2500rpm then that is not a healthy voltage...

Then I would go after a drain on the battery doing an amp reading.... If there is an intermittent low amp drain that will be tough. An intermittent big amp drain might blow the system fuse.

I will not get into how to troubleshoot/isolate intermittent drains on the battery yet. Wait see what the voltage's are... Just me.

Jim
 

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to measure really low resistance, you generally need to run some current thru the circuit to get an accurate reading. not something that would very easy to do at home. Some shops have a test machine for this purpose, like a place that rebuilds starters n whatnot
 

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Correct me if I'm wrong here...an over charged battery (if wet cell) becomes empty due to 'cooking' the battery. And if it's killing the battery due to a parasitic drain or running the bike with no charging, the battery will still have water.
 

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I think your assessment is correct if you have correctly checked and added distilled water as needed throughout the year and then all of a sudden your battery is boiling dry.
Correct me if I'm wrong here...an over charged battery (if wet cell) becomes empty due to 'cooking' the battery. And if it's killing the battery due to a parasitic drain or running the bike with no charging, the battery will still have water.
 

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to measure really low resistance, you generally need to run some current thru the circuit to get an accurate reading. not something that would very easy to do at home. Some shops have a test machine for this purpose, like a place that rebuilds starters n whatnot
Yep sometimes one needs to have some current going through the circuit... An analog volt meter helps but Current is the tell tale most of the time. Easy to do for someone with electronics basics. Sure do not want much current.

Example... A 1.5 vdc battery and a 10 ohm resistor in series with a .6 ohm coil will produce 141 milliamps of current. That is not enough current to harm the coil. If the coil has a bad connection it might open or read less current that 141.

If the coil has a couple of windings shorted, which does happen then the current will go up, one or two windings shorted is not going to produce much of a current difference. Problem is, at what point will the coil not produce enough of a pulse (amplitude) to render the CDI inoperative or create the god awful intermittent miss. I personally would want to scope it... BUT in the example of a couple of coils shorted that even may not work.... I do think scoping is the best avenue and the current test with resistance is second best.

Automotive coils create the same kind of issues... Resistance =good but get it warm and the thing starts opening, usually in the primary.

Jim
 

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Correct me if I'm wrong here...an over charged battery (if wet cell) becomes empty due to 'cooking' the battery. And if it's killing the battery due to a parasitic drain or running the bike with no charging, the battery will still have water.
Your assumption is correct

If a battery is getting excess charge through the reg/rec unit - (which happens because although the reg/rec is supposed to dump to earth if it fails, occasionally it goes wide open and cooks the battery) — constant over-charging will boil the battery fluid off

If the reg/rec has failed and gone to earth, then you can also (mildly)boil the battery through over use, but the effects will be much less

If your stator was at fault — then the results will be much the same, but first the point of stress would have to be on the reg/rec unit

The reg/rec unit has to fail before anything gets through (or not) to the battery ……..
 

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Yep sometimes one needs to have some current going through the circuit...
I run into this at work. A circuit will ohm check good but when a load is put on the circuit the voltage goes away. Sometimes even see 12v potential then 0v with load on. Too much corrosion or a bad connector involved. Just enough contact to get an ohm or volt reading not enough to carry a load.
I use a tester that injects a high current for a milli amount of time. Disconnecting both ends of the wire as to not blow a circuit board or module, of course. A simple light bulb used for a load and a volt meter measuring the voltage drop works good.
To find parasitic drains I hook an amp meter in series to the battery cable and start pulling fuses until the drain stops. Then wiggle wires and connectors in that circuit to find the drain.
 

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Oh, and my coil test is like my thermostat test. If a coil is suspect, I throw it up in the air and if it comes back down I replace it.
I know that test may not work in this particular case...
 

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Currently chasing an electrical gremlin - oh the joy. There are lots of threads on checking the phases of a stator with a volt meter but not a one of them I can find say exactly which notch on the meter I need to be using - 200, 2000, 20k? Higher?
if you are still having problems ,ask sportsterdoc. he made a post before about experience in this area, check the sticky post on 'Electrical Theory'
 
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