running rough when warm

maybe someone can help me with this one. when i first crank the bike after awhile it idles fairly well, but after it warms up or gets hot it begins running real rough. took the boots out going to the air filter and checked that all carbs were pulling air. adjusted idle to get it to at least run by itself and as it sat idling it would begin, for lack of better term, revving itself up as if i were twisting the throttle, from around 1500 rpm to up to 4000 rpms at times. timing? carb issues? oh also i could maintain a better idle by moving my finger back and forth across the tube for the air switch coming into the air filter. could actually kill the bike if i covered it completely for more than a couple of secs. that maybe normal i don't know cause i know nothing about that deal. bike is an 82 kaw 1100 a shaft

What kind of shape are the carb holders in? Had an 81 kz650 that acted just like you're describing, and it turned out to be cracks in the carb holders that didn't leak until the bike got up to temp and the rubber expanded enough to let air start seeping.

will have to look into that. i see what you're saying, course i suck at judging things like that but is definitely worth checking out. when it first starts this it sounds like it's not running on all cylinders, wonder if that could mean it's flooding out on some of them.

Get a can of carb cleaner and get her running. Spray the carb holders down from all possible angles and if your idle changes you've got leaks. Try that both after the cold start and after she warms up and starts acting up.

If the valve clearance is out of tolerance, the valves will seal when cold, but will not close all the way when hot. If you ride the bike, it will seem normal at speed, but after it's hot, the bike will run rough or die. If you let it cool while idling, the valves may seal again and the bike will rev up on its own.

Ride it on the highway for 15 minutes then come to a stop. If it dies immediately, but will restart and run rough for a while then gradually get better while riding slowly, i would definitely check the valve clearance.

The runaway idle hot is a typical symptom of a vacuum leak somewhere.

The bigtube for the air suction system won't affect running, but the vac hoses from the air valve to the carb/intake may be a cause of an air leak. An easy test would be to cap off the ports that the hoses connect to, and cap off the ports on the valve cover.

thx. i'll look into as much of this as i can tonight and let you know how it turns out.

check this out. started it this afternoon and it was seeming to idle fair but not well. decided to take it for a short test ride, less than a mile, and it fried four out of five fuses. one as i remember was looking like what i refer to as half blown to start with, this by the way i'd forgotten about yesterday. when i finally got it pushed home , damn wish i'd bought a smaller bike, i replaced all the fuses with 20 amp short fuses and restarted the bike. it idled fine after i turned the screw back down to normal. no popping no roughness and hitting on all four. don't know if the others were all too weak or if there is a short somewhere but i'll be checking. gotta hit the hay for now, but definitely look forward to some feed back on this. you guys do know your bikes.

i would go through all the connectors and clean them. It wouldn't hurt to remove the ground to the engine and clean it.
Those old fuses will get hot and melt the sorder and the fuse will look fine but will be fried. Roy