Stator Ohms cb77?

[chrisnoel]

Bench tested my stator coils with my meeter set on 200 and got some mixed results. Looks like A-B is 28, A-C is 19, and B-C is 10 ohms. Am I using a setting that is too sensitive or are two of my coils going bad? May just get the thing running and do a voltage test at each phase but I'm thinking voltages may not be very close to each other. Would like to know what AC voltages would be in good operating range directly off of each coil. Thanks, Chris.

[e3steve]

Joel, the stator readings are much a lower impedance than those values; between 1.6R & 4R. Running (and revved up past 3000) you should see 30-40VAC between each coil set, disconnected from the harness. Zero VAC when referenced to ground.

[chrisnoel]

Thanks. I figured a running test would be the way to go. I probably would have been looking for higher values though so I'm glad I asked.

[e3steve]

Joel, have you checked your meter's Ohm/resistance/impedance calibration? If you've measured those values with just one multimeter then there's a strong chance that that meter is out of cal. A while back I posted a sticky basic tutorial, where the single-asterisked paragraph shows a simple way to check individual lamps and, therefore, also a simple "meter check". Check the meter's "zero cal" by placing the probes together before each session; that will give you an idea of its accuracy and offset for the lowest of readings.

*The lamps on our bikes should vary between 2.4R (&#937;) for a 12V/60W(!) headlight, 4.1R for a 35W headlight, 6.9R for a 21W brake light, 28.8R for a 5W taillight and 72R for a 2W instrument lamp. These figures are accurate for a 12V lamp, and a bit anal, but for most lamps on our bikes a reading of <100R, bare lamp taken from its holder, is close enough to indicate a serviceable lamp.

Or keep a few known-value resistors handy, perhaps up to 1K&#937;, to check meter once in a while.

[chrisnoel]

Multi meeter I use at work is not good for automotive use so I use a cheap $10.00 meeter in the garrage. I think I have another one so I'll compare the two and also check them on a resistor. Looking at the wiring diagram I see that my figures are not so confusing. Of the six coils A-B goes through two, A-C through four, and B-C through six. Stands to reason that the resisances through the leads would be a 2:4:6 or 1:2:3 ratio. rounding down for testor lead resistance I'd say my readings of 9:18:27 make sense.