sometimes it gets washed and sometimes it gets washed and oiled
I've been running K&N filters for many years, and it's important to re-oil the filter every single time you clean it. It's the oil on the cotton gauze that traps the dirt.
I can't tell you how many times I see guys running white heavy breather filters - In fact, I wonder if they come from the factory w/o oil and the dealers simply don't realize this during prep.
Everytime I get a chance to warn riders I see running them unoiled, I often get a deer in the headlights look and they seem to think I'm nuts. Somewhere along the line, MOCO has to do a better job of highlighting this.
Also, for those who bought the HB kit for those models that don't have them, note that the kit does not include the composite support frame that you insert into the tube prior to the filter. I was kind of shocked that MOCO doesn't include that as that's the only thing to support the filter itself. I was able to look up the PN and it's only a few bucks. Although I know you FXSTSSE/2 guys got them stock, but everyone else really should add this piece.
I hope this helps.