Need ?
I'm not so sure they 'need' the oiled element . The oiled element might draw more or more free flow of air which could effect the overall performance of the motor .
I think there are members that run different filters . I run the oiled OEM 'biscuit' with a 1/4" thick piece of fine scrub pad ( for catching chunks
) . I have run pleated fabric filters that I applied K&N oil to on former 2 stroke motors with no ill effects .
Pete .
