Speaking from experience, and not knowing if the X wheels are coated or not (and not willing to risk it)...I use a nice cleam sponge and lots of elbow grease.

I had an eclipse with the allow wheels and used Castrol SuperClean on them. It cleaned great but ended up removing the coating on the wheel and looking like crap.

I suppose that there has to be special wheel cleaning solutions on the market but I haven't tried any yet.

Good luck.

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