lumpy running from nowhere

[jon the gripper]

ANY IDEAS? MY Z1000J2,WAS RUNNING FINE,STOPPED FOR AN HOUR,START UP FINE THEN VERY LUMPY RUNNING STALLING AT LIGHTS AND NO CLEAR REVVING,ALMOST LIKE DOWN A CYLANDER,ON TICKOVER IF YOU REV HER SHE STAYS ON 4000 OR WOTEVER THEN VERY SLOWLY COMES BACK TO A LUMPY NOISY TICKOVER??? NO PRE WARNING OF THIS NOW STARTS FINE BUT RUNS LIKE SHIT,ANY CLUES BEFORE I DELVE IN?

[Pigford]

Jon, if the revs are 'hanging' on a bit, could be an air leak in carb/cylinder rubbers, check if they're split or cracked.
Defo a carb thing if revs are slow to..... errrr slow

[london calling]

Jon,check the breather in the fuel cap.
Other than that just check through everything step by step.
Hope you find the problem and get it fixed quickly

[jon the gripper]

cheers for that,took carbs off,blew out all jets and a quick clean up,all rubbers ok,everything tight,air filters spotles,all 4 throttles in sync,put it all back together,fired up fine,tickover ok,better running but not like it was? if rev on tickover it slowly comes down in revs,like real slow!! no tank cap breather as custom jobby. owt else??i

[jon the gripper]

HAD CARBS OFF,CHECKED ALL FOUR RUBBERS,ONE HAD A CRACK BUT NOT DEEP,ANYWAY REPLACED IT,RE ASSEMBLED,RAN BETTER AT LEAST REVING TO 8000,BUT HOLDING ON FROM 4000_3000 REVS AND STILL NOT ITSELF? HELP!!