ORIGINAL: w8ye
In 1961, I made a Spacer free flight with a Cox rear rotor 15. I 'm thinking it was called a Space Hopper engine? Anyway, it seemed impossibly high timed. It wouldn't four cycle without changing rotational direction two or three times.
Jim
Jim,
The Space Hopper was an .049. The .15 was either an Olympic (BB) or Sportsman (plain bearing). I had the Olympic until it got stolen while I was in the service.
I'm guessing yours was an Olympic too if you used it in competition. Why would you want to 4-cycle that engine?
George