Most following for a while know I spent quite a bit of time messing with the baby Evo as well. My flying style dictates that I be pretty picky regarding mid range performance. That said, take this for what it's worth. That carb, while fine on idle and top end (which keeps many guys happy), seemed inconsistent in mid range on the Evo engine, so no love for it here.

The issue with that carb, and some others that are similar, is there is no seal between the idle mixture needle and the end of the spray bar. This leaves fuel drooling out the end of it around the idle mixture screw - as well as fuel coming from the slot in the spray bar - resulting in a sloppy mess being fed to the engine (my opinion). The fact these baby gassers are critical on their fuel metering seems to be lost on the designers here. What seems like a simple change (adding a seal) could be a game changer for that carb.

The later style Evo carb with the internal pump WAS an improvement over the original that used muffler pressure, but unfortunately, the rest of the carb parts carried over without change. That's my take anyway.... -Al