I have white DC blocks on one of mine and it still leaves black residue on the rim!
![idiot2 :idiot2:](http://www.radbmx.co.uk/forum/Smileys/smilies/idiot2.gif)
Either way they don't work particularly well, and in the rain you've had it.
I run cool stops on the rides and by fookerty do they work!
Just check my back tyre from Chester. Balder than PeterJ
![LolLolLolLol :LolLolLolLol:](http://www.radbmx.co.uk/forum/Smileys/smilies/LolLolLolLol.gif)