I could never get my knife to do an inverted climbing spin. My su-do-khoi on the other hand is a different story. They were both balanced about the same, and both had about the same control movement, the only difference was the design and power! The su-do-khoi has a ys 63 outrageously overpowered! While the knife had an os 46 overpowered but not nearly as much as the other. I don't know if its the design or the power difference, but the suky would do it evrytime. I had a lot of deflection to be able to do this around 45 degrees. I have been entering a flat spin from a stall turn recently looks cool. but you can get in them in many ways. On my sudokhoi if you would just pull verticle and push both sticks to the top inside corners it would enter a climbing inverted flat spin. Happy flying