Don't use greasy stuff, like WD40 or polish--your brakepads will not be able to grip and you will not be able to stop.

Have you tried soap and water? My rims on my Luna are black, so I don't have this problem. Or is it that they just seem black because I've never cleaned them ?? I'll have to go check.

Would Pedro's bike wash work? Or Simple Green? Rinse well and no polish or oily stuff!