I recently purchased a used 03 wr from a local used bike dealer the service history is unkown as well as the miles. What i was wondering is how can figure out how many miles or how much time is on it? Tires are not stock they are excellas and the rear is worn, the rear sprocket is not stock. I am a profesional tech the bike looks clean has good compression The valves were in spec accept for center intake which is at .0035''.Now what i do not know how many times the valves have been adjusted. Does anyone know if the valve shims are awalys the same size when assembled at the factory, I have seen a few engines where the shims are awalys the same size when new because of extremely tight manufacturing tolerences.And what i was thinking was that i can caculate how much wear is on the valves by the shim size change from stock, just an idea. Or some other way to figure time on the bike?