1982 KZ250 LTD Belt Single- No Spark

Hello,Long-time lurker, first-time poster. I've been working through a KZ250 barn find I picked up and have been combing through everything this forum has to offer regarding wiring and related info.So far, I've had to replace quite a bit. To start, I installed a new CDI because the original one was grounding itself and instantly blowing the main fuse. The new CDI solved that issue. I had to eyeball most of the wiring, but now all the lights work, including the neutral light, and the main fuse no longer blows.The starter solenoid also had to be replaced since the starter button wasn't working. I was able to bypass it to get the bike turning over, then replaced the solenoid, and now the starter button works—in the center position of the handlebar toggle switch. I assume the left and right positions are kill switch functions because the button doesn't work in those positions.At this point, though, I still have no spark.I checked the ignition coil, and the wire basically fell out of the rubber boot at the coil end. I replaced it with an aftermarket coil that fits, but still no spark. I also checked inside the headlight, and everything seemed okay. Power is definitely getting to the system—when I press the starter button, I can feel some warmth, which tells me there's current.The stator and rotor look to be in good shape. I figured I don’t need to worry too much about those right now since they’re just for charging, right?I’ve got a new rectifier on the way because the old CDI would cause the current one to smoke when connected. Maybe there’s a grounding issue near it, though I doubt the rectifier itself is the fix.I’m wondering if the kill switch might still be interfering, preventing the igniter/CDI from grounding properly. The coil is getting power, but I’m still not getting spark. I even tried jumping the coil directly from the battery—still nothing. That’s when I started thinking maybe the igniter needs to ground itself somehow for the spark to happen.So here’s my big question:Can I bypass the kill switch? And if so, can I run a lead from the igniter to the coil as a bypass?Would it make sense to splice the yellow and yellow/red wires together at the kill switch, run them directly to the igniter, then ground the igniter’s green wire to the frame or battery negative? Then just run a positive lead from the igniter to the coil?Honestly, I’m not sure if any of that makes sense. Any help getting spark would be really appreciated!

I think you might benefit from reading the "elec fundamentals and fault finding" guide link is in my signature. The coil should have an ignition live from the kill switch, the CDI switches a ground to the other side of the coil. If the kill switch is getting warm then that is an issue ! yes you can by-pass the kill switch as a test but I wouldn't recommend it as a permanent solution (if the throttle sticks open trying to turn the key off may be tricky !!)

Ok, so I’ve been going through all the wiring religiously along with the electrical diagram. While checking voltage and resistance, I noticed that when I tested the ohms at the pickup coil prongs (the ones that go directly to the stator), I got absolutely no reading. Bypassing the kill switch didn’t give me spark, so I figured the pickup coil might be the issue. It looks like someone tried to replace it before but failed, since both screws on the pickup coil were stripped. It took a few hours and some patience, but I finally got them out. I’m guessing that’s why the bike’s been sitting for decades. I pulled a pickup coil off a smaller bike just to test for spark, and it was reading around 145 ohms. I figured I’d need something closer to the 300–500 ohm range to get proper spark. I tested both the non-working coil and the borrowed one using the 2k ohm setting on my multimeter in horseshoe mode. I still need to check the clutch switch—I’m assuming there might be a safety mechanism in the turn signal/high beam cluster, but I didn’t see anything about it in the wiring diagram. I know my neutral safety switch is working, because I tested it at the stator and the neutral light comes on. Does anyone have a recommendation for a replacement pickup coil? I couldn’t find one specifically for my KZ250 (mine reads PU100-01), so I was thinking about trying one from a Bayou 300 since those seem more available and have similar resistance values. Also, @Wookie58 — your link for the electrical info in your signature isn’t working. Any help would be appreciated. Thanks!

Strange, the link seems to work for me ? go to filebase - general - electrical  and you will find the guide there

Thanks Wookie ill take a gander at it today I appreciate it, I usually only deal with bikes from the early 70s and late 60s where they are kick start magnetos and not CDI. Can anyone help me with my Aftermarket pickup coil. I see some used ones from ebay but they are hitting $50 to buy/ship. The aftermarket bayou 300 ones are like $10. As long as the measurements are the same and the ohms resistance it should be ok?

Stjames wrote:

Thanks Wookie ill take a gander at it today I appreciate it, I usually only deal with bikes from the early 70s and late 60s where they are kick start magnetos and not CDI. Can anyone help me with my Aftermarket pickup coil. I see some used ones from ebay but they are hitting $50 to buy/ship. The aftermarket bayou 300 ones are like $10. As long as the measurements are the same and the ohms resistance it should be ok?

If you look in the file-base there is a manual for a KZ200 and the supplement towards the back has the test specs for the pick-ups along with test procedures for the CDI - Don't forget that as well as the correct electrical values the physical size of the pick-up is important as the "air gap" between the rotor and pick-up coil is critical.