I may still try it then. I won't spray it on but apply it with a brush in a very controlled space. The remaining dirt is embedded into the rough surface of the areas between the spokes mostly in the crooks. There is very little now but it is very stubborn especially in those spaces. I am thinking of using Aircraft Remover which is essentially a stripper in an aerosol can. Very caustic stuff. I will use it to remove what clearcoat was applied to the wheel. I will end up using some kind of polish to restore the luster of the aluminum. Like I said, between the spokes is a rough surface and it probably didn't have a coating. That is where the remaining crud is.