Until my most recent purchase, I've run Kawasaki's. All but my first (a 23 horse, 2002 model) have used a little oil. I use 10-40 synthetic normally, but used straight 30 dino on my last mower the first 100 hours. It still used some oil. I never actually tried to measure the consumption, but I never bothered with adding oil until it got below the halfway point in the "safe" area on the dipstick, and that generally was at around 50 hours or so. I can't believe these figures of an ounce an hour or more. That would mean in at 100 hour oil change intervals, one would have to add 3 quarts of oil, more than the amount it takes to fill the sump in the first place.
Guessing, I'd say mine might consume 8 - 10 ounces in 100 hours.
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