Fixed up three '90's era hand-me-downs and although line tension is very good during maneuvers all three pitch up when entering the upwind side of the circle. I don't mean hunting; they pitch up to the top of the circle, even when entering that side of the circle on landing. It's hard to keep them down and level during flight. On one of these landings, with all line tension gone, it glided down to a perfect landing (spectra lines). So I'd say the balance is OK(?).
The builder added reversed trailing edge stock on top of the wing trailing edge as if to act as an aileron and compensate for a warp, but I didn't detect a warp. I shaved half the thickness on one and the flight seemed slightly better. There's tip weight as the outboard wing is a bit down on landings.
The engine thrust line is level with the fuselage centerline.
Any ideas?
Ara