Fast idle is slow to come on

[geezer#99]

Your fast idle is already set. Your choke blade being excessively closed won’t let the idle come up. As the choke coil warms up it forces the choke blade open. Motor runs leaner and the idle naturally increases.
A simple test for you.
Start it up stone cold. Pop aircleaner lid off. Fire it up and quickly open the choke blade enough to get the rpm to increase. Use a long screwdriver to push on the blade. Might only need to open it a 1/4 inch.
Easier to do this with two people maybe.