Before jumping in and repairing watches there are some things that need to be studied to understand how the mechanism works. There are books on the subject that cover a lot of these principals. I think your timing problem has to do with the center of mass which is adjusted with the MERIDIAN SCREWS on the balance wheel. This is the same principal as moving the weight up and down on a clock pendulum. Bob covers this in his clock videos and you should watch it as a first step. Second step, get some books and study.