misfire between idle and higher rpm

82 Xj650.......bike starts and idles fine. When rpm's get higher it sputters until it reaches a certain rpm. Then, it revs up like it always has. No tach, so I'm not sure of the specific rpm in which it smooths out. This started a day after I washed it. The bike is old and I bought new coils(wires) and end caps. No difference. Removed tci box and desoldered circuit board. Nothing (looks) abnormal on circuit board. As bike warms up......the #2 cylinder exhaust pipe is the last one to get warm. At a higher steady rpm. The #2 cyl pops/misfires on occasion. Went through carbs and cleaned them. I don't believe it's carb related. Remember, this started happening the day after I washed it. The tci box controls the ignition advance on each coil right? If so, each coil fires two plugs. Why is it that it's only one plug misfiring? Any suggestions on what to start looking for?

 

Don't count on the wash being related, it might be, but just as easily it could only be a coincidence. Your pipes should all warm up at the same rate, and even though you say you went through the carbs, it does sound carb related to me.

Did you wet set your floats, bench and running synch your carbs? Are you sure you got every passage clean including the pilot/mix circuits? And just to eliminate them as a problem have you checked primary and secondary resistance on your coils? Have you checked compression?

 

Most certinally carb related.
Are there any modifications to the intake or exhaust or is it stock?
When was your last valve adjustment done?

 

The Diaphragm Pistons could be affected by oxidized Piston Bores.
Not Rising and Falling unimpeded.

 

Washing the bike was purely coincidental. Wet setting my floats cured the problem. Thank you so very much guys. I don't know what I'd do without this forum.