ORIGINAL: Sourkraut
The way I heard the diff. to be between the .46FX and the .46FXI, is that the "I" in FXI meant that it was already "run in" and required no run in before flying, thus making the NexSTAR truly RTF. I may be wrong but that is what I heard. I have the FXI, FX and AX and they all seem to run the same.
Cheers
Curt
They're NOT run in. Like most other engines the carbs are pre-set at the factory to approx starting points before shipment. They still require the same typical minimum break-in proceedure as any other OS non-ringed 2-stroke.