Sorry to post again in here, but I have a question and an observation.

What are the reasons we are interested in using a gasoline engine?

I can think of two major reasons: 1) the obvious price differential between gas and glow fuel, and 2) the reliability gained by fully controlling the ignition point using the electronic ignition.

Here is a possible alternative: E85. This is a fuel made of 85% ethanol and 15% gasoline. It happens to be available locally for the 'Beautiful People" here in Seattle, the land of fruits and nuts, to "Save the environment" in their flex fuel SUV's and pat their egos. Go figure...

Anyway, I can get it for around $2.40/gallon last time I checked. Being ethanol, it is a higher octane fuel and thus more resistant to detonation than gasoline, but with the higher flow rates should produce more power on a specific engine than gasoline would. It would also provide a significant amount of cooling as the ethanol absorbs a great amount of heat to vaporize (not as much as methanol, but more than gas by a long shot).

Cheap ignition units are easily available now. The RC EXL ignition with a 1/4-32 spark plug can be had for ~$85 or so and is a copy of the excellent CH Ignitions Synchro Spark. It retards the timing at lower RPM so the idle is smoother and starting is easy (NO kickbacks!).

Again the biggest problem of converting a glow engine to gas is the bushed connecting rod. It sure would be nice if somebody made a conn rod with a pair of roller bearings for some of these engines...Of course that would be fairly expensive.

Now if only OS would make a solid, LIGHT, durable 2.0 cu in 2-stroke! That would likely match or beat a YS 1.60dz.