When I bought Kawasaki Dirt bikes (100's); the dealer told me to use Castrol 10W30 only (with filter). According to him anything that runs high RPM's needs a quality oil like Castrol. He said that most other oils had a paraffin base; and Castrol did not Not knowing; I followed his advice. Now everything I have uses the Castrol. O'Riley runs it on sale always; and I use their Microgard Filter. The specs are the same as Wix. A 5 quart oil change and two filters does Mule and the Cub Cadet