Cleaning valve covers

[outnumbered]

I'm wanting to get mine powdercoated, but is there anything that will brighten them until then? One of mine has always appeared to be a little dull.

 

[MUTT]

i dont know about cleaning them, but by the end of next week i will be ordering these from justin.
http://vtcoa.com/forums/showthread.php?t=6999