Z1OwnersClub GB

Hi
1981 kawasaki KZ1100 been running fine until a few weeks back, now running on 3 cylinder ... number 4 cylinder has good spark but plug wet when removed any ideas?

No idea how you can have a good spark and a wet plug?
Perhaps you have a fault or intermittent connection in the HT lead / plug cap area. Maybe when you took the plug out to check for spark, you inadvertently made the connection good again. Try mix and match with alternative plugs, caps and coils

Just because it'll spark out the head doesn't mean it'll spark under compression. Go the diagnosis route or just put new plugs in
Diagnosis route, swop plug to another cylinder and see if the fault moves. If it does, chuck in a new plug. If it doesnt check ht cap / lead conection. Maybe cut lead back by 1/2 inch or so to expose fresh core for clean connection.
Swop ht caps to see if the fault moves with the cap.

Thanks for the replies

Changed leads 1&4 around and number 1 cylinder ran fine so I know it’s not the lead also changed out plug... dropped it on it’s side the other week while moving it around the garage thinking maybe a stuck float?

Rubber mallet the bowl normally sorts a stuck float. However, if the plug is wet then fuel is getting to the cylinder so why is it not firing?
Swop plugs to with another cylinder and see if fault moves.
I suspect faulty/fake plug. NGK by any chance?

Tried swapping plugs.. real head scratcher!

So fault stayed with the same cylinder?
Got compression on that cylinder?

Fault stayed the same.... lack of compression was on my mind but no way of checking... not sure when valve clearances were done trying to eliminate all the easy stuff first.

3rd change of “new” ngk spark runningsweet again.... give that man a coconut
Thanks for your help fellas...
Any recommendations on plugs? Going to change them all out.

Good news. Use denso w22es. Far better plugs than ngk.
Get them from a reputable dealer though. There are plenty of fake plugs about both ngk, denso, champion and every other make you can think of.

Nipon Denso

Sounds like flooding fuel into the cylinder, could fuel level be too high or float sticking, usually does it on cylinder 1 when left on side stand for a few days,