Help please-weak spark!

[uglyd1]

I have a 94 Kaw 750sx. It has been running great, but Sat. I went to restart it and it wouldn't fire. Took it home, pulled plugs and they looked good. Checked spark and there was spark there but it looked weak. It was just a dancing yellow spark, not the good solid blue one that most things have. The spark never went away, it just looks weak. Put plugs back in and got it fired up. Where should I start looking, stator or cdi? Not sure how strong of a spark this ski should have, I've read that stock ign is weak. . I saw an MSD ign enhancer for 230.00, but I want to make sure that this would fix my problem. I don't know how a bad stator, coil, or cdi will start acting when they are malfunctioning. Any voltage checks to do or any other checks I can do to pinpoint the problem. Maybe it is just weak since it is stock and old? The ski is well cared for and is dried out after every ride. Any help or guidance would be greatly appreciated. Thanks in advance to all who can help.

 

[SUPERJET-113]

Yes, your right about the weak stators in the first few years of the 750SX..
The stator coils in conjunction with the flywheel magnets generate heat and that along with the engine heat itself will kill the stator(heat soak)and then you would have no spark for awhile until it cools..
I went through this BS for 2 stators on my 94 750SX, then I sent a bad stock stator to Ricky Stator(www.rickystator.com) and they rewound it with heavier wire and I never had a prob.
The stock stators would test fine when its cool then you heat it up with a hair dryer and it would fail the resistance tests.

I'll bet its the stator..:wink:

 

[SUPERJET-113]

Soem other stuff from my old Kawi notes:

Coil Test -
You should have a Black/White wire and an orange wire.
Put your meter on the lowest Ohm's setting.
You should read 0.08 - 0.1 Ohms

Now Take the spark plug boots off. They screw off. If the wires look green and crusty cut them back a 1/4" while they are off.
Then stick a probe into each wire. Set your meter on the setting that will read
up to 5000 Ohm's (5K).
You should get between 3.5 - 4.7 K Ohms (3,500 - 4,700)

Pick up Coil Test - Small square black piece under cover.
These are the Blue and Green wires coming from the front of your engine.
You should get 396 - 594 Ohms

Pull out the four prong connector and unplug it. Check AC voltage from the pickup. Purple to red with the engine cranking should show .5 (1/2) volt AC.
Green to blue should show a minimum of about 70 volts AC.

I'll bet if its not something simple its the stator...

 

[ski4]

on 3 kaws i had the same prob. i have one left with a jss stator now hope it gives me a long life

 

[uglyd1]

Thanks alot super113. That stator problem makes sense cause I rode for a while before it wouldn't start again. After a 45 min. trailer ride home, I could get it running. Thanks alot for post with all the electrical test. I am printing it out right now. Thats exactly what I was looking for, and I will go make the elec checks tonight. I will check out that stator guy you mentioned. I don't wanna spend a ton of cash cause I want to upgrade to a newer sj. Thanks again, it's really appreciated.

 

[SUPERJET-113]

Thanks alot super113. That stator problem makes sense cause I rode for a while before it wouldn't start again. After a 45 min. trailer ride home, I could get it running. Thanks alot for post with all the electrical test. I am printing it out right now. Thats exactly what I was looking for, and I will go make the elec checks tonight. I will check out that stator guy you mentioned. I don't wanna spend a ton of cash cause I want to upgrade to a newer sj. Thanks again, it's really appreciated.

Hey man, glad i could help and welcome the X!!:headbang:
Let us know how it goes...