I had small amounts of baked on brake dust when I bought my car. I tried several polishes and gave up. Started using a spray on wheel cleaner. After a while I noticed the spots were gone. I don't remember the brand I used, but now use Meguire's Gold Class. I spray all four wheels (cold) then start back on the wheel I first sprayed with a soapy brush. Maybe if you try a bottle, by the time it is gone your stains will be gone too.