What you are seeing should just be the center serving wearing on you. If this wears all the way through you need to get it reserved right away. If you shoot your CB with out a center serving you could break a strand on your string and then bust the entire string giving you a dry fire affect if it were cocked when it happened. It is normal for it to look a little "worn", but if it looks like they are wearing most of the way through, then take to a shop and they should reserve it for you for less then ten bucks. Its better to do it when you want to rather then out the door on the way hunting and then you notice it.