Flew the SkySurfer last week and it just didn't seem like it powered all the way up, sorta staggered around the sky (it was windy) so I brought it down and ceased operations because of that and it was too windy for my skill level. Yesterday I put it on the bench and ran the motor...a weird buzz ensued when running it up so I shut it down and checked the mounting screws. Yep, one had fallen out and lay in the bottom of the fuse and the remaining three were all loose. Got them all tightened and that solved the buzzing problem. The lack of RPM's was my fault for not setting up the ESC correctly after the initial binding. After rebinding and correct adjustment of the throttle now I have a screamer that ought to really move that thing around the sky. Lesson learned...periodically check those motor mount screws and RTFM when binding and setting up your ESC.