A method and brush kit for cleaning and improving the roughness average of aluminum or aluminum coated valve cylinders and other open or blind bores in virtually any type of mechanical device by removing burrs and embedded particles within such cylinders and bores wherein the method provides a kit of a predetermined number of cylindrical brushes having metallic or nylon strands that are coated or impregnated with an aluminum oxide abrasive material. The method is particularly adapted for use by technicians in the automotive, marine, farm, aircraft and the like repair industries for treating transmission valve bores or cylinders and other open or blind bores and the like.