Odd. The ARF I have has visible right thrust. My first Cor-Star (coroplast Four Star copy) had zero thrust, and I ended up putting washers under the left side of the motor mount because it pulled so hard to the left on takeoff. Zero thrust may be OK for a gutless 60, but I would seriuosly consider adding a degree or 3 if going with anything bigger. Especially if you like short take off rolls. The 4* only needs 15 feet before it's airborne.