When it is shown running, this must be on air pressure rather than fuel. Still an amazing piece of work.
I agree, it was on air pressure. Probably an issue with sourcing spark plugs in that size, and associated ignition, oil pump and other things which are hard to scale down, including fuel injection and or carburetors.
Many small engines of this physical size (think r/c model airplanes and the like) are actually powered by 2-stroke engines using a catalyst ignition system.
http://en.wikipedia.org/wiki/Glow_plug_(model_engine) You heat a platinum glow plug up with a battery, prime the system, and get it running. Remove the battery, and the engine continues to run. The fuel is a mix of methanol and nitromethane, and the red-hot platinum is a catalyst for the reaction that turns the ethanol in the fuel to formaldehyde. Castor oil is mixed in with the fuel, so it is a two stroke w/o any mechanical oiling system. More:
http://www.rc-airplane-world.com/model-airplane-engines.html Nonetheless, that V12 was an amazing feat of miniature model making and machining! That small cam shaft is pretty amazing.
