Here are a couple of the diagrams I made for a thread I started on the .40 size Ultimate biplane from World Models. They had hardware in the ARF for coupling the ailerons top-to-bottom. The left hand picture shows what resulted with their rigging. The top aileron was moving much less than the bottom. Shown in the diagram is the result of their rigging. What's amazing is that you actually get a different difference when the coupled ailerons are moving UP!! So when you move your ailerons, one side was seeing different lift/drag than the other side!!

The second pix shows how to connect the ailerons so that they will all operate exactly the same. It's dead simple to do and took me less time than it would have taken had I used the kluged up hardware that was included.