The dihedral wing on most trainers and the small rudder throw make KE a nearly impossible maneuver on trainers. Yes there are those that can do it.

You can try pulling the nose up before you enter the maneuver. That will at least get you started at the right attitude. Unfortunately, the combined effects of small rudder authority, rudder induced roll on dihedral wings, and the inherent desire of the plane to roll back to a belly down condition are all working against you.

If you're to the point where you're trying to learn knife edge flight, its time for a second plane.

Brad