Polar why don't you put a set of gold valves in ya k5 , do it yourself save you heaps , as for the front brake , careful bleeding with oversize disc works wonders , the later master cylinder seem to be better for some reason to the one on my kx450 14 is the best of kawi I ever had , I have one off a cr250 , could be about 98 vintage , worked good , bled easy but the hose would hit the handle bars if you have the levers down a bit like I like them to be , so I change back to kx one and put a kit through it and bleed it well.