Listen to Camss69 & Campy. Rich is for ringed engines & steel-sleeved engines. The "pinch" fit at the top of the cyl in an ABC/ABN engine will be degraded by running the engine too rich during break-in. Run it just into 2-stroke mode, at full throttle in ~ 3 min bursts. Then cool & repeat until you have gone through a couple of tankfulls