Main Motorcycle: 09 Speedy
Join Date: Jan 2010
Location: Sacramento, Ca.
I am fumbling through the voltage checks. I am no electronics wizard at all!
Going step by step in the stickie posted by DeCosse here is what I've found:
A ‘cold’ resistance check for shorted diode/SCR:
Unplug both input & output plugs from R/R;
With your meter set to read resistance (use a diode test if the your multi-meter has one), test from each pin of the three pin plug, to both the red & black wired pins of the 4-pin plug; NONE of these should read short circuit (zero resistance); depending which way you bias the test leads, you may get some reading (from the forward bias of the component) but it must absolutely not be a short. If you see a short on any of these readings the R/R is defective.
Set to 20M I got similar readings from all 3 plugs.
1.5 when connected to the Black
2.5 to 4.5 when connected to the Red
Next, do a resistance check on the stator (check at the cable connector going back towards the stator itself).
Measure between the three respective combinations of the three pins:
This time each of these should measure almost short circuit (very low resistance in order or about 1 ohm)
With my meter set at 200ohm I measured
This next check is probably the simplest/quickest way of determining a stator problem - in majority of cases a bad stator will be indicated by failing following test:
Check resistance from any one pin to the engine ground terminal – this should not read any indication – maximum resistance or open-circuit.
If you read ‘short’ in that last test, then your stator is bad.
(if open, it is not quite guaranteed your stator is good however - but in majority of cases a failed stator will fail this isolation test)
In this test I got no reading in Ohms. Literally the Voltmeter didn't do anything.
Check the AC voltage output from the stator with engine running:
Leave stator disconnected from the R/R and start the engines.
With meter set to read AC Volts check
All three should be the same value – any significant difference of one reading will indicate a bad phase and the stator is probably defective.
At idle this should be ~ 20V* and rise to ~ 70V* at 5K rpm.
I hesitate to use absolute numbers here as this can be different between models and test equipment and especially the engine rpm!
What you are looking for is same value between phases and like increase on each phase as rpm increases.
If any of the above tests raises suspicion, pull the cover & inspect the stator. It is simple to do and can set your mind at ease by seeing what it looks like. Hopefully NOT with 1/3 of it a black charred mess!
In this test It didn't measure any volts at all on any configuration. The bike was cold and this was the first I started it up all day. Just double checked this again and still nothing.
Am I doing this right? Any helpful thoughts or reccomendations? Should I go ride her and come back and check things after they warm up?
Keep the rubber side down!!!
Last edited by DFUSEME; 11-11-2012 at 11:35 PM.