If you are rebuilding an old motorcycle, vapor blasting the engine cases is a must for restoring parts to better than new condition. Vapor blasting is a media blasting method that involves the use of ultra fine glass bead and water. The water is injected into the media stream and cushions the blow of the media against the part. This cushion allows you to blast over tight tolerance areas such as gasket surfaces without fear of material removal. Vapor blasting does not remove material, but peens the finish and closes the cells of the base metal to almost polish the piece. Check out some before and after examples of vapor blasted parts.