Yes J-Tab, The missing in the mid throttle is due to the Walbro design. The carbs on 4 strokes go too rich in the mid range thus causing the rough running. That is why when the carb is adjusted for 3/4 open it, as you said, the high speed needle can be leaned in for proper mixture for the top end. The good news is it will also lean the midrange so the engine will run better at part throttle and yet loose little to no power. I have a saito 325 radial and I had to use a 24 oz tank because the lousy carb on it goes very rich in the midrange where you want to do most flying. I bought an OS carb for the 240 Pegasus and turned it down on the lathe to fit the Saito. The mid throttle is greatly improved and now I have longer flight times on 16 oz!!! The engine is so much more enjoyable to fly. I am with you, on youtube most Moki's are very rich and run poor at part throttle settings. The turbulator is a great for midrange running due to the evenness of fuel distribution. It sounds like your plane is nearing completion. I look forward to hearing a flight report. -Tom