we are at 50 hrs oil and filter, using , hell i dont remember but it works. i know our oil is plenty dirty at 50 and could never go 100hrs, that is way long. our engines state at 50hr intervals except the diesels go 100, but conversly it states 200 on them but we like fresh oil.
we dont get much past about 1200-1600 hrs on a air cooled engine though b4 you can tell it has worked alot, have blown a few that had issues, but over all they still run but we get new mowers at that point.
all is fair in love and grass!
Man, it smells like sheet, do you smell that!!