Stalling

I have a carb issue on my ’81 KZ 750 LTD (4 cyl). When I flip the (carb adjust) lever up (rich mixture) she starts right up. She will die right out, though, if I don’t give ‘er some throttle. I then tap the lever down a bit (leaner mix) and she’ll idle for a few seconds then sputter and die unless I lift the lever back up to rich mix. She’ll then come back to life for a few secs but then will sputter ‘till I tap the lever back down halfway.
Unless I give ‘er some throttle the only way to keep ‘er running is to lift, to full choke, reduce to half choke, lift, reduce, lift, reduce, etc., etc., etc..
After running a few miles, she’ll eventually (usually) adjust to the point where she’ll idle with the choke in the “off” position but there’s no guarantee she won’t die when I stop.
Any suggestions?

Hi there

Give us a bit of history on the bike.

Has it always run like this ?
Is it new to you?
does it have stock airbox with airfilter? or individual pods ?
Exjaust - stock 4 into 2 or aftermarket 4 into 1 ?
What colour are the sparkplugs ? black and sooty or white ?

Offhand I cant point to anything specific and think you will need to take the carbs off for a closer look at what's going on. Recently I had a hard start issue and found that moving whe choke lever did not make the choke flaps/butterflies move. Check the action of the choke linkage. You may need to go further and dissamble the carbs and do a complete overhaul. Could be a combination of things. Incorrect fuel level. blocked jets, wrong jets, incorrect mixture settings etc.
Sorry I can be more specific.
With my 1980 750E1 I raise up the choke lever all the way, hit start and it fires right up. After 20 seconds it will start to to stumble a tad or so I can reduce the choke a little and it will smooth out. I'm riding out of the driveway on half choke and I can let it off altogether at the first traffic lights. The last part of coke travel is just a high idle. When fully warm I have the idle set at abot 1250 rpm. Which is around what is recommended. Cant remember exacty.
Good luch

my kz440 was doing this as well. I opened up the carbs and one of the diaphragms was torn. The right side wasnt getting enough air. and barely firing up. I would check your carbs. it could be a number of things in there.