I think you need a really hot glow plug to keep it running on 4-stroke (or maybe power it all the time).

But like stated in quoted thread, I don't see any reason to use 4-stoke (Ryobi) for airplane - to many parts for to deal with. Engine is to heavy for the power out. When I asked the question there I thought that maybe it will have bigger torque so it can run 20 or bigger prop. Nope. So not worth the trouble when 2- stroke for the same power/torque is twice lighter and three times cheapper.

RysiuM