Virtually all the conventional trainers will perform best balanced at 25% mac not 30%. Expressed another way that ideal starting point is the quarter chord or you could simply divide the distance from the leading edge to the trailing edge by four and the sum is the distance back from the leading edge that is your ideal target balance point. This applies to any straight chord untapered wing and indeed most trainers including yours is straight chord.

This 25%mac or quarter chord is also on most airplanes at or very near the position of the main wing spar.

"How will I know if it is too nose heavy" Very simple just lift it on two fingers at the target cg point under the wing and if it sits level it is balanced at that point, If the nose angles down then it is nose heavy and the cg is forward of your desired point, do not angle the nose down for "Mother And Country' when balancing your airplane.


John