The problems you had with the tuning are more or less inevitable; chainsaw carburetors do not give car-like drivability. You can overcome the off-idle stumble by making the idle just slightly richer than would be ideal, and you can usually overcome the stall when you suddenly drop the throttle from full-bore by making the high speed jet just slightly richer than ideal. It's a world of compromises - 2 strokes are like that. On the other hand, who wants to carry around the weight of a 4 stroke chainsaw or trimmer?
