ORIGINAL: downunder
ORIGINAL: Artisan
Never try to run any engine without some kind of load on the crankshaft, such as a flywheel or a prop.
A flywheel isn't really a load on the engine except when it's accelerating because the flywheel's inertia will slow down the rate of acceleration. It'll still peak out like a shaft run (which will loosen the screws holding the front end and split the disc valve on an old K&B 40 pylon engine....ask me how I know
).
------------
You are absolutely right. Thanks for the correction.
I was thinking of utility two-strokes (gas/petrol) with cooling fins on the flywheel and a shroud, or boats in the water and forgot about not having a prop in the water available when running just a flywheel.