I just got a 1982 kz1100a as a project. Got it running. Thoroughly cleaned and set the carbs, made sure the airbox boots seated properly and had no vaccume leaks.
The bike runs good when cold, pulls hard, idles well. However, as it warms up, it will refuse to idle and will hiccup when accelrating hard.
When I pull the plugs from when it stalls at idle, all are black, not wet, but dry black, indicating a rich condition or maybe ignition problems?
Im thinking it may be either the coils or ignition pickups..?
Here is a video from a somewhat cold start to warm up...