Just as on an Amal carb, the smaller inner slide is used as a choke. I am unaware of any choices of main slide. With the Three-Jet Binks you have no throttle stop screw, so have to rely on cable adjustment only. You also have no control of the primary air mixture, and all you can do with these things is change jets ! As I have said before on this website, I am not a fan of Binks carbs, BUT I do have LOTS of spare parts available….
Brian
