Since I , In Most instances, de-stroke the Acc Pump anyway. The B is functional. Still don't mean the "B" is the Best Carb for That Job...tho addition of a ThunderJet helps! No mikuni for me tho...the CV's that I have used work exceptionally well. Remember Larger Venturi, with like same ports and volume, only results in Lower Signal...so Poor Manners!
Remember...Most Carb problems are really Something Else.. usually an Intake Leak. Which is another good Bet..especially if it occasionally Coughs hard enough to stall!!
I would still take a Critical Look at Battery/Charging. Knowing how a bike acts, with low voltage prompts me to at least investigate...before buying carbs/kits!!