Whip out the trustly old toothbrush and go to work on them
yellow?
you sure its brake dust. brake dust usually makes it black. depending on how long they've been covered, it may be harder to get off.
i use super clean when mine get real bad. that stuff is pretty harsh though. i've never been able to get mine completely clean. as the time goes by they get worse and worse.
GO PATS!!!
i bought some stock 16s from a friend of mine and they had yellow crap on them when he gave them to me. i got most of it off with wheel cleaner, a rag, and some good old fashioned elbow grease. but theres still some on it that i cant get. im not sure what it is either.
blue pen eraser works great, it will take some time but it gets every detail.
14.82 @ 97 mph