There are many reports on the net of MAF sensors being destroyed by oiled filters. They may or may not have some basis, K & N say their filters are not a problem. The thing is that oiled filters actually pass more dirt an very quickly clog up and become less efficient than OEM air filters. Given that the gains are somewhat illusory is it worth the trouble?

This makes interesting reading
http://www.nicoclub.com/archives/kn-vs-oem-filter.html

By the way when it comes to foam filters on throttle bodies it is a different issue unless someone can work out an intake system with an airbox such as used on large bikes.f

Peter

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