This engine looked to be new, never used. However it did have some fuel residue and was gummed up a bit. But I found out by running it that it certainly had never been broken in. As I ran the engine the top RPM slowly increased and the idle RPM slowly was reduced and more reliable. I put about 90 minutes on the engine today.
Prop is a Rev-Up 12x5W 4-cycle, glow plug is a Thunderbolt standard long, fuel is Powermaster 15%, temperature outside was in the mid 90's.
Max RPM achieved was 8000, and lowest idle speed was 3000.
The engine is VERY quiet, and even rivals the HP VT-21 I ran yesterday!
This is an interesting piece of engineering. Cast crankcase, billet head, billet carb, belt drive for the valve drum, ball raced, two needle carb. It's marvelous to look at, and it runs sweet.