Simple, I use SIMPLE GREEN to clean my K&N filter with. Do'nt know if you can get it down under. But I would think that WAL-MART is there to. Also I use it to clean my whole mach. It's BIO DEG wash your face with it if you want to. On the oil side, I ONLY use K&N oil to re-lube it with. Taking no chances here.
O- spray on the green and let it sit for hmm a min or two, wash off with warm water. Let it air dry, it's best to have 2 or 3 filers that way one of them allways ready to go. (THIS IS VERY IMPORTANT) The K&N filter doe'nt work right if you do'nt let it dry right. 24 hrs is norm, your mach will act like it's burning rich (suxing in the excess oil).
Hope this helps
I forgot, HOW (OFTEN) BEFORE EACH RIDE (I LIKE TO WIN)