I haven't made any changes to the choke coil rod. I disassembled the carb and had the stripped fuel inlet threads repaired. After cleaning the carb I put in new gaskets. There was no problem with how the carb ran on fast idle before the rebuild. Perhaps I used a thicker carb to manifold gasket. I'm not sure. Before adjusting the rod I'm going to try and loosed the fast idle screw. It should reduce fast idle rpm but it may also allow the fast idle cam to fall more readily.