Glenn, question #1. Do you do a full tech at the end of every race day? On every mower? If not people are cheating. Question #2. Do you know the stock cam numbers for every make and model of mower engine running in your stock classes? If you do, you're pretty smart because engine companies do not publish this info. Question #3. Not that I am insinuating anything, but who techs your equipment? Not saying you ever cheated, but it does open up the real possibility.
I maybe was born at night, but it wasn't last night. I've been around racing in general almost my entire life. I've been in lawn mower racing before there was a USLMRA (24 years). Racers cheat. Maybe not all of them, but enough of them do. I can name names of people who cheat(ed) in mower racing, and I can tell you what they did. And you would know some of them.
To deny that there is cheating is lunacy.