l'll have to check the manual again to be sure but my memory says the Cg is supposed to be 3 1/2" from the leading edge of the wing and mine is set almost 3 3/4". I would agree your problem may not be a balance issue. But I doubt that the recommended Cg is designed to give a true "neutral" balance. Most likely it is designed to be just slightly foward of "neutral" for stability. Even though mine is set near the recommended limit of range for the Cg, it still requires a little elevator when inverted at less than 3/4 throttle or so.