Drone engines are pretty neat engines. It is about as simple as one can get with a model diesel engine too. The plain bearing models can be easily converted to RC by making an adapter for them to fit a small RC carb on them.

There is a adjustable diesel head one can get too. It pops up from time to time for sale here and there. Here is one example.




There is evena  glow head for them too:





Here is one of mine being test run.

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