Dear Dave,
I am Indeed honoured to Have such a Prompt Reply from the YS Prof !! APC 12-7, OS Type F Plug. Would these present valve clearances be the cause of almost impossible starting after engine has warmed up a little? Because when I hand turn the engine slowly to feel the kick, its just not there when she is warm.
Greetings From Sunny South Africa
Dave Black
PS. With Your Proffesional help I WILL master this engine. I bought on Advice that it was the finest small 4 Stroke in the world.