81 kz550 spark problem

hey guys i recently bought a 81 kz550 for 500 bucks, it ran rough so i rebuilt the carbs. i had rode the bike when i bought it and it stumbled aorund and the choke had to be on full way to even run at all. any ways after rebuilding the carb i put the bike back together and tried to starty it. wont fire. i checked to c if the carbs are getting gass and they are so i checked to see if im getting spark. the 2and three wires are and the 1 and 4 wires arnt. the 2 and 3 have great spark. anyways what do u guyds think could be causeing the no spark outa of the 1 and 4 wires. i aint sure if its wires, coil, points or what . any ideas would be greatly appreciated. lol thanks fella

For some strage reason Kawasaki has the bigger 4's primary ignition coil wiring different than what's on the smaller 4's. On the bigger bikes, the left ignition coil has for the primary(small wires)BLACK and RED firing plugs #1 and #4.

The right ignition coil has for the primary RED and GREEN, firing #2 and #3. I'd check the sparkplug caps too as a resistor inside can actually gain resistance or fail from heat/vibration.

I'd remove the gas tank and check the wiring for corrosion and loose electrical connections too.

Start with new plugs and wires just as a tune-up item. But it sounds like the coil either isn't getting power or isn't putting out juice. Could be many different things but start with checking to see the coil is getting a full 12v+. Then check to see that the pickups are working right. If it's getting voltage and seeing the signal then you need a new coil.

Since it just started you may have bumped a wire when you pulled the carbs.

I got my '82 kz550 for $300 so I feel your pain lol!

Not sure if this will help but all I have for the KZ550...

PM LoudVHX, he's pretty experienced especially on the electrical side of things on these KZ's...

i had this issue with my 80 kz750e i ended up replacing the spark control box and it cured the problem but do check your coil wires for power first

The RED wires on the ignition coils supply the 12 volts and it comes off the right handlebar run/stop switch.

The BLACK and GREEN wires from the coils go to the IC Igniter(it actually gives the coils their grounds, firing the sparkplugs).

I'd get a multimeter and read from the RED wires to any good place on the chassis for a ground.


Primary winding resistance (where the small wires go) should read 1.8 to 2.8 (3 ohms)

The secondary winding (where the sparkplug wires go) should read 10.4 to 15.6 k(thousand) OHMS.

If you're getting 12 volts to the ignition coils, I suspect the IC Igniter may be bad. The member Loudhvx has a replacement he designed using off the shelf GM modules:

home.comcast.net/~loudgpz/GPZweb/Ignition/GPZgmHEImod.html

okay guys ill check the ohms and what not but besides that i took the green wire off the 2 and 3 coil and put it on the 1 and 4 which wasent sparking before and got spark but the 2 and 3 didnt. i switched em back and right back to where i had started. ive chekced wires and fuses and there all good so what would cause one coil to be getting juice but not the other one. is the red wire the ground ? cuase all i swithed was the green to black and the black to green and the oppsoite coil worked and the other didnt. let me know what yas think

The RED wire is the 12 volt supply line for the coils(their wired together so both coils get the voltage).

Like I mentioned earlier, the BLACK and GREEN wires go to the igniter giving the coils their grounds.

so by me swithcing the black and green wires at the coils and the oppsiote one would work then before would insinuate that the ignaiter is bad ?

Sounds like it, or it could be a wiring issue. Go thru all the troubleshooting procedures in the service manual before you build/buy an ignitor and then find it was a wiring problem. These old bikes use a lot of connectors that either corrode or come undone easily.

If you do need an ignitor, let me suggest building one of these:

home.comcast.net/~loudgpz/GPZweb/Ignition/GPZgmHEImod.html

ok well i cut the tape off the hole wiring harness. no splices or anything on the black and green wires going to the ic ignitor to the coils. i am getting 12 volts at the coils but the coil with the green wire is the only one working but if i put the green wire on the other one that one will work but not the orignal one so i know the coils are good leaving me to belive that the black wire that runs to the ignitor sint getting the gorund its supposed to so i think the ignitor is bad fellas. what do ya think.

It can be the igniter or the pickup with the black and blue wire. Unplug the small connector at the igniter and ohm out the black wire to blue wire. It should be about 450 ohms or so.

If the pickup is ok, then it's probably the igniter. You can make one pretty cheaply as Po Boy and Mfolks mentioned. home.comcast.net/~loudgpz/GPZweb/Ignition/GPZgmHEImod.html

The only thing to add to the ignitor project would be a reminder that the small parts should be protected from vibration. A little coating of 100% silicone would help, or even just a loose wrapping of tape. Definitely use stranded wire to connect to the modules.