First; make sure the throttle plate seats completely when the high idle screw is backed off. If you had the throttle plate out to say, replace the throttle-shaft bushings...you have to be really sure it's shut completely before you tighten up the throttle shaft screws.
Second; some Bendix's came with an accelerator pump shaft that had three sets of hole heights in them for "squirt" adjustment. Some Bendix's came with the hole height in two different places. One was drilled for a Sportster...the other was drilled for a 74 cu. in. If you feel you need "less" squirt try removing the accelerator pump, remove the roll pin in the shaft, measure the drill size of the shaft hole, and drill another hole 90 degrees to the original hole about .075 above it. That will give the pump less stroke.
Third; make sure the pump jet that sits in the throttle body squirts directly through the slot in the choke plate. It's designed to hit the throttle body plate and atomize. If the stream hits anywhere else...it will cling and you'll get the after effect you describe. The throttle body shaft also has seals...they could be leaking air. The pump valve could be dirty and sucking fuel. You also have to understand how old this carburetor is, too, and that there were several Bendix's. If you can, try and get ahold of a factory manual that has the Model 16P12 in it.
Fourth; check your advance weights and the advance weight springs. If the weights don't return right away the engine tends to return to idle a lot slower.
Sixth; you might want to invest in an adjustable main jet kit. Here's one from J&P Cycles By: 47Knuckle-Dragger on: 6-19-2007