Starting idle opening on a 257 carb?

[Mike Cathey]

I'm setting up the throttle linkage on a Gizmo 30.5 with a 257 carb in a gas scale. What's the starting point idle butterfly opening?

 

[Rich Jones]

I like to use the outside (high) needle as a guide. I set the tip of the carb arm a little bit to the left of that needle. It is kind of trial and error but that is a good starting point for me.