Crazybiker

What do you mean topping out? Do you mean that the lever is able to touch the bars and still not lock the brake? There is a number of causes for this but the most likely is that the seals are broken, check around the lever and the slaves for any oil that has leaked out. If this is the case then you will need to change the offending seal. Also check the hose for any kinks/ wear e.g. the tyre rubbing on it, this could cause an air leak meaning a new hose is required. It is possible to bodge this by covering the worn area in Epoxy but a new hose will be much better.