I was flying my Fury today, and when I did my first inverted circuit in FFF the engine lost all power after about 15-20 seconds. I flipped the heli immediately, came down on the stick, was ready to set it down in tall grass, when the engine came back to life. Second flight, same problem. I took the canopy off, checked the clunk, checked the GV-1, everything was fine. I open the high end needle two clicks, and the problem went away. Turns out I was too lean.... FYI, inverted hover was fine all day, since that is controlled by the mid-needle on the OS61WC.
Sometimes, it is better to be lucky than good!

Rick