You know, that was one of the things I wondered about (was mine just too heavy), since the FS 70 is a bit porky. To balance mine, I had to mount the battery behind the wing saddle (made a removable door). It's quite possible I was just flying a brick which required the high speed landings to avoid stall on approach. I know there's a ton of fellows out there that really like the GP Cap .40, maybe the best of them are using lighter engines. (Hmmmm )