I have a Scag Tiger Cub, 100 hrs. 19 hp Kawaski. Noticed I am using approx. 1 gallon of gas every 30-40 minutes. Does this sound about right.?? I am cutting with double blades, but wasnt much better with single blades. Use 93 octane most of the time. The cub has the standard air filter on it. Would I be better off installing the cannister type ? Any help greatly appreciated.