I used to build and fly model airplanes. I built a tiger 60 (not the arf model, made for a .60 two-stroke engine or a .80 four-stroke)...
http://www.carlgoldbergproducts.com/tiger60D.htm
I put a .91 four-stroke on it. On its first flight, it lifted off and went perfectly straight! (usually you have to make some adjustments). The bad thing is that the thing took off just a little above idle. I don't think I reinforced the wings and how they attatck to the fuselage enough to handle that engine. I haven't flown it since in fear of a lack of ability to fly it, and it sits in my basement.
I haven't flown a model in over 6 years now, but when I do again, I'm going to start with my trusty strudy birdy (
http://www.hobbico.com/airplanes/hcaa1010.html , it's a really underpowered plane, but oh well, good to learn with). When I was learning to fly, the crystal went out on the radio when the thing was at full therottle and about 500 ft in the air. I watched it turn over and dive down straight into the ground. I found the engine nearby, replaced the carberator, bent the tail back into shape, put some epoxy on the cracks in the fuselage, and it was flying the next day. That plane is freakin durable, i mean the fuselage is made from a drainage spout, I had to replace it once, so I went to the hardware store and cut a new one out one afternoon.oh yeah, and for a real cub, pick up a trade-a-plane. You can find cubs for like 20 grand in that thing! Of course, you're going to need a pilot's license for that number.