Originally posted by Stazi:
Don't use brushes or compressed air and you won't damaged the filter media. I've never found a need to do either of those things to clean my K&N's over the many years I have been using them.



I've noticed without some sort of physical contact, K&N filters don't get clean. Hard to avoid brushes or compressed air. Gunk stays in the grooves even with multiple application of the cleaner.

I'll add that to my list of 'con's' right next to worrying about oiling too much after cleaning(which messes up the MAF sensor).