20 Finally, three tries and quite a bit of frustration later, we obtained an acceptable pattern. A good pattern should have contact in the middle of the coast and drive sides of the ring gear teeth. Although difficult to see here, ours was a little high on the teeth but perfectly centered from heel to toe. We decided to let it fly and fortunately everything worked out. This is where patience really comes into play--you must be willing to take everything apart as many times as necessary to get the pattern right.