Phil, I read a few years ago that the OEM were so durable that you can treat them as if they were a K&N. You can get the clean/oil kits with out buying the filter.
Spray the cleaner on it, let it sit a bit, wash with cold water from the inside and dry. When dry apply a LIGHT coat of the spray on oil.
I have two or three and I always had one ready to go in so i didn't have to wait for it to dry.
The first time I did it I had a white shop rag in the sink to see if any of the fibers were being washed out with the dirt. I saw nothing to indicate it was a bad practice.
I used to wash the OEM filter in my VTR, CBR and VFR's. Remove the filter, tap it a couple of times to dislodge the wildlife, then a quick vacuum.
Next, drop it in a sink full of warm water with some liquid laundry soap. Let soak an hour, a gentle pass with a soft brush if necessary, followed by a warm water rinse.
Air dry and Bob's your uncle
Never oiled mine as I found the filtering performance was top shelf. M2C
