Choke does'nt work much

Good evening gentlemen

I ride a kz1000 B4 LTD 1980. I change the cam chain last week. When i finished to reassemble, I start the bike, with the choke on, and the revolution of the engine was staying at 1500rpm.
Before i changed the cam chain, the choke was doing a great job, and the bike was starting promptly. Now i have to start the bike with choke off and keep the trottle open for a while and the idle does'nt stay, i mean, the bike shuts down if i stop holding the trottle.

Today i opened the valve cover again to check if the timing was still ok, and it is actually ok.

Everything electric is fine.

So, what could affect the choke?

Thank in advance

You say you went in and double-checked the chain timing...did you actually set it at TDC on 1 and 4 ,and then do a pin-count,between the exhaust cam,and the intake cam?

exactly! 28 pins and the lines are all in there right place. Nothing is missing there.

What about any vacuum-lines that were connected to the carbs?
I have a different set-up that you,so I'm only guessing at this point.
Did you pull the carbs off at all?
Did you disconnect anything to do with the carbs?

Everything is ok around the carbs, vaccumm lines and all.
I'm gonna put back the valve cover, start the bike and see what is going to happen...

Well, i put back the valve cover with a new gasket, torque the bolt just enough, start the bike, and realise that nothing have changed. The bike starts, the choke doesn't go higher than 1500 rpm.

I checked the vaccuum connected to the reed valves and everything is clean, not obstructed, the carb is ok, i reinstall the tensioner.

Well, i don't know what could affect the choke.

Thank for your help

double check that you haven't turned up your idle speed adjustment (intentionally or by accident) as the chokes will not function worth a poop if the throttle is open very far.

may or may not be the case, but it doesn't cost anything to turn it back in and see if it helps. Count the turns in and return if it doesn't help.