Rock Oil Factory Foam Kleen is designed for the serious offroad rider and is to be used in conjunction with Factory Foam Air Filter Oil.
It is a superior high performance foam air filter cleaner.
Allow the filter to soak in the cleaner for a few minutes. Rinse air filter under running tap until water flows clean, in extreme cases this may take more than one attempt.
Allow to dry naturally then re-oil using Factory Foam Air Filter Oil.