Ok, I'm going to step in here and disagree. It should never be said that balancing laterally isn't important and it won't affect much if it's out of balance. Both of these statements are incorrect. Lateral balance is very important in the scheme of things with a plane, and it can greatly affect the way a plane can fly. You can take the best flying plane in the world and turn it into an absolute dog if the lateral balance is out of whack. The lateral balance affects so many things that we do from simple trimming the plane to affecting the way a plane handles in aerobatic maneuvers. IMHO it's something pilots should learn as they get started in this hobby and should check on every plane they fly, including their trainer.

Checking the lateral balance is fairly simple to do. The only thing needed is some fishing line, or strong string. Tie a loop around the crankshaft of the engine right behind the spinner, and then tie another loop around the tail of the plane. Now use the line to lift the entire plane off the ground. If the plane is out of balance it will tilt towards the heavy side. If this happens weight needs to be added to the wing that raises up. Stick on weights can be added, or the covering can be cut to add weight inside of the wing and the sealed up. The farther out on the wing that weight is added the less weight will be needed to balance the plane.

Ken