RE: How does a gas engine act when hot?
Trixie is right spot on with his take on gas 2 strokes overheating. I have been racing, flying and using 2 strokes for many years. I have had few if any heating problems. In my airplanes I make sure I have adequate air intake and lots of exit area. They will tend to loose power when they get hot, and many times quit altogether. Running them rich can tend to mask this however. I think your main problem with your DR1 is going to be adequate exit area for good cooling. The two holes at the top of the cowl should let a good amount of air in.....