sorry but it doesn't matter how tiny... in karting the tiniest of differences... .05 second can make all the difference between winning big, and losing out....
the exact regulations are there... engines have fiches... you brake them.. your excluded... there's a not a rule in any motorsport I know of that says... "you can go a little over the specific fiches if you want... only makes a tiny diff anyway". The numbers are written down, and the line is drawn quite clearly....