Cylinder misfiring, advice appreciated.

I have an 83 KZ1100 that has been sitting up for about 18 months. Prior to this, the bike ran beautifully. I had just completely rebuilt all four carbs and all was well. Just cranked it up a few days ago and it was misfiring. Cylinder 3 and 4 seemed okay, pipes got hot quickly. Cylinder 1 was misfiring, pipe slowly got warm. Cylinder 2 wasn't firing at all, pipe stayed cold. I pulled the carbs, removed the bowls and stripped them down. Removed main jets, pilot jets, mixture screws needle valves, etc. Cleaned everything up, blasted them with carb cleaner, blew the passages out with compressed air, adjusted the float levels and put them back together. Cylinder 2 did have some crud caked in the pilot jet. Put the carbs back on and I still have the same problem. While it is running I can pull the #1 and #2 plug wires and I do get spark. I also installed new plugs. Any advice on how I can further troubleshoot this issue?

Thanks-

Run compression check and check voltage going to coils.also check for vacuum leaks.

#1 and #4 have about 120 psi, #2 and #3 have about 110 psi. I have about 11 volts going to each coil with the ignition on. I also checked the resistance of the primary and secondary coils. All was within specs according to my service manual. Even so, I swapped coils to see if the problem followed the coil. It did not. The number 2 carb was the one with the vacuum line that operates the petcock. The vacuum ports of the other 3 carbs were capped. I moved the vacuum line to the #1 carb and capped #2. #2 is still not firing.

I guess at this point, I need to pull the carbs again and really go through #2 again with a fine tooth comb.

Anything that I am missing here?

Cheers-

Okay, I pulled the carbs again and broke #1 and #2 down again. Went thought the passages with carb cleaner and compressed air. Everything looked fine. Put them back on and the same problem exists. #2 does not fire and #1 appears to be misfiring.

I'd really appreciate any advice on how to further troubleshoot.

Thanks-

DJ wrote:

... adjusted the float levels and put them back together....

Bench adjustment often misses the mark.
Would check levels in floatbowls using clear plastic tube test.

Good point. I'll do that this evening. Thanks for the suggestion.

I would start with the basics! Is the #2 plug sparking?

jrjstuff wrote:

I would start with the basics! Is the #2 plug sparking?

Yes, the plug is firing.

Okay, still working on this issue on and off. I am pretty sure it is simply (or not so simply) an idle circuit problem. When I crank it up, if I can fiddle with the throttle and get it revving, that dead cylinder starts firing. It does nothing at idle.

Question1, what is the purpose of the plugs covering the pilot jets (not the air screws)? I mean this is where the engine is supposed to fuel during idle. Is there another passage that feeds fuel to the pilot jet from the side in between the jet and the plug?

Question2, in the bowl there is the needle valve, main jet and pilot jet. There is also a long metal tube that extends from the carb body down into the bowl. Does this feed fuel to the choke?

On my Mikunis, the pilot jets are fed fuel upwards from straight underneat through the main jet.

There is also a long metal tube that extends from the carb body down into the bowl. Does this feed fuel to the choke?

Could this be the overflow pipe?

Are you saying that there is a passage between the Main Jet and the pilot jet chamber? I guess it would have to be that way since there is a plug covering the pilot jet.

Can you tell me how to get the needle jet out of the carb? Are they pressed in, screwed in or what. My manual doesn't tell me how to get them out.

Thanks-