Radials?? Bias? Which kind, i run my radials at 30 and they wear nice and even and ride well, if you run them too high you'l wear the center out, an easy way to check is to draw across the tread with chalk and see what wears off if its too high just the center will rub off, so then you let air out little by little untill you have a nice even contact patch. or you can drive thru water and see what kinda tracks you leave on the pavement, same kinda thing. which ever is easier,