2007-2009 Suzuki LTZ90 factory service manual, Page 17Get this manual
PERIODIC MAINTENANCE
Fill wash pan proper size with non-flammable cleaning solventImmerse the air cleaner element in the cleaning solvent and wash it Press the air cleaner element between the palms of both hands to remove the excess solvent: do not twist or wring the element or it tear Immerse the element in motor oil, and then squeeze out the excess oil leaving the element slightly wetA Non-flammable cleaning solvent Motor oil SAE #30