I read some info on this oil and liked that it has a high zinc content for added anti-wear protection. So i called Valvoline and spoke to a rep there to ask if this oil is safe to use in my two small lawnmower engines (Honda 160cc and Kawasaki twin cylinder FR651V.) As of today, the Honda has the 10W30 while the Kawasaki has the 20W50. I ran both for a few minutes to get the oil circulated. I have read differing opinions about using this oil in non-racing or high performnance engines---some even saying the oil will turn "sludgy" and/or actually do harm. Any expertise is surely appreciated.