Choke lover

I'm sure this is an easy fix but here goes...
Solved an air leak problem but now she loves the choke (get your mind out of the gutter).
'80 Kz550 start/runs fine on choke but when warmed up and I take her off choke, she revs really high (almost red-lining) for several seconds (max about 30) and then idles lower and lower and dies within 3-5 seconds.
Is it something with the fast/slow idle circuit?
I did clean the carbs as well as I could last year (hasn't been ridden since). Some screws were stripped/seized thanks to the previous owner so I couldn't get to all the needle assemblies.

Sketchproject wrote:

I'm sure this is an easy fix but here goes...
Solved an air leak problem but now she loves the choke (get your mind out of the gutter).
'80 Kz550 start/runs fine on choke but when warmed up and I take her off choke, she revs really high

classic symptom of a vacuum leak. did you check the intake manifolds?