When applying up elevator, the giles rolls hard to the left. It seems to only do this in the last half of the elevator travel on the way up (i can use a little bit of elevator to fly around, but anything over 1/2 and it rolls on its back). Does anyone have any idea how to fix this?

I have already checked:

1. Lateral balance
2. Elevators are exactly level with each other and travel together.
3. CG is at 5 1/8". The book says 5 1/4", but that seems very unstable.

Can anyone help?

chris