The limiter with the pins in it is on the idle jet. The blue collar on the main needle is the locking collar for the needle valve ratchet spring, $1.50 each when you break one, as I did last week. The 1.5 mm setscrew allows you to turn the ratchet spring in a convienient direction to stop the needle valve pin if your adjustment locates the pin at the ratchet spring proper. Loosen the setscrew, and rotate the ratchet until it doesn't interfere, tighten and you should be good. I installed an A3 glo plug, it now runs up and down throttle like it should. I still have it a little rich until I see what tendencies it develops in the air. Nice smooth idle, good transition. Now I just hope the hotter plug doesn't burn up the motor or cause some other unforseen problem..... Getting ready to take it up in about 20 minutes, so we'll see...