1980 z1 classic fouling plugs

Got lucky and found the specs on these injectors. Attached picture. 

Warren3200gt wrote:

Cullen wrote:

Warren3200gt wrote:

No kawasaki I know runs well with resistor caps and plugs. One or the other or none but definately not both!

Both is a sure way to foul plugs. 



I agree but it was running ok back in May/June with the same set up.  Bike sat for about 3.5 weeks and when I started it, it was fouling and way rich. Put in brand new plugs and same result.  I will see if I can dig up some old non resistor ones for trying.   I started thinking coils, then ignition box etc.. but when I swapped the 1 coil with a known good one and no change, I crossed that one off the list.



 

If it's suddenly all four plugs it's bound to be electrical before it gets split into two for the coils. Have you got 12+ v at the coils? If not and two resistors per ignition line will only compound the condition.
Simple things to check and remedy first. 

I am going to measure all the resistances today of the ballast resistor, coils both primary and secondary as well as the igniter box and see what I get.   Lots of write ups about newer style coils not needing the ballast resistor because of their primary resistant value being higher.  I either need cap ends that have little resistance or plugs that are non resistor style too. 
 

Cullen wrote:

Got lucky and found the specs on these injectors. Attached picture. 

That's a bonus, you can now check delivery rate as well as spray pattern etc 

I am attaching resistance readings from this mornings measurements.  I cannot get the IC Igniter readings to show what’s in the manual, the igniter on this bike on Partzilla shows a 21119-1040 which also aligns with a 1984 550 LTD part but when you look at the graphic pictures they are different sizes…. The one I pulled out shows it’s a 21119-1017 on the label which is different than above.  I am wondering which I should go with and it possible the igniter is part of the issue?  All the other readings are close to spec, nothing grossly over in resistance.

Still don't see a volt reading feeding the coil +

I measured with just the key on since the injectors are still out.  Both coils read 10.8v.  Are you asking me to measure it once the bike is idling?  I will do that once I put the injectors back in.

Which spark plugs are you running?

Cullen wrote:

I measured with just the key on since the injectors are still out.  Both coils read 10.8v.  Are you asking me to measure it once the bike is idling?  I will do that once I put the injectors back in.

What was the battery voltage when you had 10.8v at the coils (any more than 0.5v difference signifies a problem) maybe time for a by-pass relay mod 

Spark plugs are NGK BR8ES.  I am still trying to locate some non resistor ones.

Wookie58 wrote:

Cullen wrote:

I measured with just the key on since the injectors are still out.  Both coils read 10.8v.  Are you asking me to measure it once the bike is idling?  I will do that once I put the injectors back in.

What was the battery voltage when you had 10.8v at the coils (any more than 0.5v difference signifies a problem) maybe time for a by-pass relay mod 

the plot thickens…. 10.9v key on ,  battery at 12.12v.  Start the bike and the voltage goes to 7.8volts on both coils when measuring the green or black(depending on coil)  to ground. Crazy drop there and the bike can barely idle without me giving some throttle. 
 

That is a huge drop when running. I am surprised it does run. Did you by any chance measure battery voltage when it was running?

The drop when not running could be caused by dirty or corroded connectors. Carefully cleaning all the connectors in the ignition circuit with a dedicated electrical contact cleaner like Deoxit might make a big difference. 
That big drop when running makes me think there is something in addition to dirty connectors. There are some good tutorials in the Filebase for diagnosing electrical gremlins, and I suspect Wookie58 will be back around when it is evening in the U.K.

Added 4 pictures of the various battery voltages at each stage.  Battery seems ok.  Seems as though I have a drain on the system.  I just pulled the key switch out and cleaned up those contacts with some 2000 grit sandpaper. Nice and shiney now.  Yellow/red wire through kill switch is still at 11.84 when the battery is over 12v.  I need to take apart the kill switch next.