Ramair filter servicing

Ram Air says to only use their "specially formulated" product - maybe just to sell more of their product, but their filter is made of foam vs the k&n being a paper type material, so might not be compatible
The RAMAIR stuff IS NOT OIL. And new it feels dry and sort of tacky. The Cleaner does not smell like a solvent that much either.
 
Off-road dirt bikes use foam filters and I imagine any good brand would work. I do caution not to use too much and to let it sit and soak in/ dissapate overnight.
 
Well I think the real question is, "How does one know when the filter needs to be cleaned?" Mine has about 6000 miles on it and I can't detect any dirt, maybe a trace of dust, but really how does one tell? Should we just clean them every spring?
 
It depends on how much dust you are riding through. K&N warns of Over cleaning as a slightly dirty filter actually filters better. If it looks dirty, yes clean it. If it does not look dirty, I would not worry.