ive heard it said before that with drilled discs its best to clean out all the shit that gets stuck in the drill holes to avoid them cracking...

since ive got drilled/grooved on mine n they been on there a while now i think its about time i did this...

anyonw know what method to use? i was thinkin of just using a brush and some brake dust cleaner, but dunno if thisll be abraisive enuf