RE: Saito 125 RPM's???
Don't spend a lot of time thinking about when it is fully broken, it will happen as you use the engine. I started something new {to me anyway} with the low end adjust ment. I set the engine to idle at just below the rated idel RPM with the glow driver still on the engine, if when I remove it and the engine drops in RPM then I put the glow driver back on the engine and lean the LE a touch and repete the process until there is no engine RPM drop. When I remove the driver and there is no RPM drop the LE is about just right. Then I test the engine my old way and check for any rich or lean problems. So far it has worked great. I just started doing it this way this summer and have been happy doing it this way. Remember, changing the prop is going to change your RPM.