Lost my spark

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Snails
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My Lui packed up the other day, no spark, and after I found I had no spark for the ignition and having tried replacing the plug and cap I ended up getting recovered :( :( :(

Anyway I've now carried out a test with my multi meter to see if the stator is outputting properly. I've set the multimeter to V~ 20 and it outputs c4.3 when I turn the kickstart by hand. Is this what I should expect?

It's got a homemade 12v conversion based on a PK electric ignition.

I have another question. What is the black wire for off the PK ignition stator? I don't currently have this wired up to anything. I don't think it's the cause of my problem but when running the lights are much dimmer than expected and I'm wondering if that's the cause.
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wack 63
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You need to do resistance tests between the white and red , then white and green stator wires. The black is an earth and would probably be best connected to the frame or at least run a seperate earth between the frame and motor. Try this first and it may cure your problems.
thackers
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Ed, could it be the black pick up box on the stator? I know they are prone to breaking down, I think you will need to re check the timing after replacing one.
Snails
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thackers wrote:Ed, could it be the black pick up box on the stator? I know they are prone to breaking down, I think you will need to re check the timing after replacing one.

I really hope not. I'll try what wack suggests with earthing the black (even though it was not earthed when it was working I guess there is no harm in it and then try the continuity/resistance tests. I'm assuming that there should be continuity between them?
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wack 63
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The Lui motor can only get a poor earth to the frame thru the cables and probably the rear shock/engine bar but I wouldn't rely on them. The lights should be as good as a Vespa, so you either have a stator ,regulator or earth problem. If you connect your meter, on 20v AC, to the "out" terminal of the reg you should get around 12v out. If you have the Sticky book it shows how to test the resistance on the red, green and white wires.
Snails
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Thanks - I've got the old Red version of his book, don't remember that being in there but will double check. If not I have a friend who has the newer version.

The funny thing with the lights is that before I correctly configured my regulator the unregulated output kept blowing bulbs and was pretty darn bright.
Snails
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Finally found the time to check out the stator as per stickys book
check 1 White or black wires to engine casing (as have not removed stator from engine) = 0.1 to 0.2 @200 ohms setting
check 2 White or black wire to red = 112
check 3 White or black to green = 450 @ 2k setting

So to me its seems to have passed. I also then earthed the black wire mentioned previously but there was no change. I guess the next step is to swap out the CDI for a known good?
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wack 63
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I would have thought the LT coil was reading low at 450 Ohms. The Haynes manual suggests around 500 Ohms give or take 20 Ohms
Snails
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Stickysbook actually quotes 450 as being the desired level in a wY for it to be spot on seems too concidental. Would it being low just lees to a weak spark rather than non at all? Think will try swapping to Cdi just to rule it out one way or the other
Snails
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Finally running again. It was the CDI. Only took me a month an a half to find time to fix it. Jeez.
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