Perhaps worth comparing to the 30 mm units on the T140V? 190 main jet, 1.106 needle jet, std needle, needle position 1, cutaway 3. Let us know what you have fitted. From your description in the earlier post it sounds like possible cutaway/needle/needle jet incompatibility and that your mixture weakens off excessively relative to the sharp increase in air flow as you open the throttle. Weakness is generally spluttering, hesitation under load and dying as you crack the throttle, overrich is generally lumpy running, missing under load and slowness to increase in revs on no load. Or it could still be electrical of course.