I would say to first check and see the difference between pos and neg expo on your radio as they can be different amongst brands. The easiest way to see this is to set your expo so it is activated by a swtich. Then move your stick just a little off of center and hold there while activating the swtich. If your control surface moves more when you activate the expo then it is the wrong way and will make it more sensitive. It should reduce the throw at those low stick positions when you activate the expo to make it more controllable. I do agree with others here in that you should need very little to no expo in that type of plane. I just don't see how you could possibly need 60% expo. I run 45-55% on my 3D aerobat with huge control surfaces and 50+ degrees of throw so something is clearly wrong.