The K&N filter should not be cleaned all that often! Only when it is VERY dirty should you need to do so. Every time you clean a K&N filter you loose some of its filtering capability. 25 times is the max number of times you can clean one. Then you should throw it away. It says so in the instructions!
Maintenance of the filter is best. Gently tap out any loose dirt and re-oil where necessary. As the filter gets dirty it soaks up a bit of oil(giving you more filtering surface)that you will need to replace.
