This means nothing at all but I will pass on a little secret. These four strokes will run very well as long as the valves are opening at all. Anything is about enough. They aren't putting out peak power but they will run. That's why I check mine every year. If you think about the valve lash or gap it's a low of .004mm to .010mm, that's a bunch of slop to play with. Anyone should be able to adjust them if you just read the instructions. When I was building VWs the gap was .006in set cold. Just kinda giving you an idea of what you can get away with. These engines are very user friendly!!