Speaking of engines, I saw a photo of a Ringmaster with a 4 stroke engine mounted. 

Any ideas on using 4 stokes for CL?  Most of what I see are RC engines.

   There is a rather extensive forum for exactly that. They work quite well, and had bursts of popularity in the mid-80's and later the early 2000s.

    Brett

David,

Go to the forum home page and you'll find 4 strokes under the "engine" section.  Lot's of info to keep you busy for a while.

I went to the forum.  Thanks

I  am currently using Saito 62 in one plane and will use Saito 40 in another. Make sure you look up the name Bob Reeves and do what he says.
for $40 he will modify your Saito Carb to work perfectly for what we want in stunt. Learn how to adjust your needle setting as it is much different than
2 stroke. The disadvantage is that the 4 strokes shake a lot. So make sure and build the front end well on your plane. They weigh more that most
2 stroke also so make the nose shorter on  your plane. If you are not going to use Ro Jett ,or PA, or Electric this will provide you
lots of steady power when it is set up correctly( See Bob Reeves information and Tulsa Glue Dobbers Web Site). Correct fuel, carb and glow plug
prop,you use venturi size to adjust the rpm. 8200-8500. Props that load the motor. I use them on semi scale planes that are draggy
and maby heavier that I like them to be. You can use big props also.

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