You're right, Skull, looking again I can see round slide BS34 Mikunis fitted from 1980 on. Good carbs, but they won't play well with those tapered oval small fabric filters; not enough still air volume to let the slides function with much stability, and no competent tuner would fit that combination (though most "expert" stylists would). Try large (as in 4" long) foam filters instead, or fit nonvacuum carbs. Stalling when coming to a stop or downhill under even engine braking is usually a symptom of low float level (=high fuel level). The change in attitude of the bike pushes fuel high to the front of the bowls, causing momentary flooding. That's easily fixed. There were 2 types of floats, brass and plastic, used in early and late BS34s, and they took very different float level settings. The "experts" may have been unaware of this. Farmer, you have a lovely machine with a lot of potential. Looks like all it needs is a few tweaks and a little money to be a real premium ride. Enjoy the project!