How often should this be done? How do you know if it needs cleaning? How do you clean it? Does it need oiling afterwards, and what with? Is that enough questions? :P

I do my pipercross once a year or every 10k.

I just swill it out under the tap sqeezing it to get the crap out.

Then leave it below a radiator for 24 hours.

Mine is oil-free, so I think a K&N you'd need to buy the spray.

Lol i text the same question to my entire phonebook thismorning! no bugger answered haha. Mines green cotton tho, they sent me oil with mine tho so that indicates I should oil it. Only done 2k miles since I put it in so mite just leave it till service next month (feelin lazy)

You can buy a kit for the Green filter with oil and detergent but most people just buy the oil and use washing powder in warm water in a bucket.

Should be done every 5k and lightly oiled with the correct oil.

As above, clean it every 10-20k miles. If you use the popper K&N cleaning stuff then once dry you will need to oil it again. But DO NOT over-oil your filter, it will kill your M.A.F.

I do my pipercross once a year or every 10k.

I just swill it out under the tap sqeezing it to get the crap out.

Then leave it below a radiator for 24 hours.

Mine is oil-free

did it come like that from new ?

pipercross filters are usually oiled, and if yours is supposed to be oiled, and isnt, your letting loads of crap into your engine, these performance filters rely on the oil to catch a lot of the dirt