Perhaps of more relevance to motorcycles during my service late last century (Australian Army) all small Engines I.E generators,welder s Etc and all B vehicles used OMD 110 which is Broadly equivalent to a mono grade SAE 30 oil
That's pretty thin oil for the hotter climates...Postwar OMD 330, used by UK forces, equates to an SAE50. I use 40 in the winter and 50 if it's a warm summer (which isn't often these days).
Wartime lubrication charts show '50 HD' for engine, box and primary....Ian
Ian
I am Far to young to have any personal experience with an M20 Australian service but Small engines Generally air Cooled used in Stationary roles used this oil in all seasons but i would be the last person to advocate this use in a M20 indeed any Motorcycle just generally commenting on the term OMD.
Perhaps of more relevance to motorcycles during my service late last century (Australian Army) all small Engines I.E generators,welder s Etc and all B vehicles used OMD 110 which is Broadly equivalent to a mono grade SAE 30 oil
Cheers
Ron FTLDU
They still use 30W oil in most Briggs engines.
Honda & Kholer specify 5W 30 or 10 W 40 depending upon the engine.
What you have to remember that most small engines are govened to about 80% of max revs.
Motorcycles are not.