Motorcycle Repair: 1986 gpz 1000a1, air fuel mixture, kawasaki gpz1000

Question
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Followup To
Question -
1986 kawasaki gpz1000-a1

gpz missfireing on one cylender.changed ht leads and caps,checked coils, compresion,plugs and carbs.also carb linkage we have also checked valve clearance.
i have one plug that is always black and sooty,it is number 2 in the fireing order.any idears would be helpfull.
thanks paul.
Answer -
Hi Paul,

#2 plug indicates same carb's air-fuel mixture is excessively rich. With the information given, I suspect the carburetors need cleaned, synchronized, and adjusted.

Respectfully,
Mark Shively

I have had the carbs balanced and mixtures set. Someone has sugested that it could be a coil breaking down when it gets hot could this be possible. Thanks for last reply hope to here from you agian soon. Paul.  

Answer
It is possible the coil is not working properly when hot and /or under load. If this is the case, the problem would exist on two cylinders assigned to that coil. If isolated to a single cylinder, the gremlin lies between the coil windings and combustion processes, such as faulty secondary lead, cap, or plug, or poor ground.

I still suspect the carbs need adjusted. It's not easy to tune carbs and often requires removing and reinstalling them several times.

Respectfully,
Mark