Im NOT talking about WINDING the secondary spring door, Im talking about bending the choke pull-off to the air door as shown in this figure.

After establishing about 1.5 -2 turns on the spring tension then bend this rod for this clearance. I think you'll find this is the cure; and only then play with spring tension and door stop to tune the fuel curve and the actuation of the air door.

Ive tried to 0.040 clearance like it says, but on my big cam I have to run it tight against the stop as was suggested by tuners to me.

If you need the complete instructions Ill email my complete pdf of the manual.