Are we talking about the Katana 50? After reviewing the specs it says .55 2-stroke, .82 4-storke, or 14cc gas. Since a 14cc gas equates a .91 you would be correct. I was planning on an O.S. 82a since I was not anticipating any 3D flying. I know that plenty of guys are powering theirs with .91 4-srokes and the like, I'm a bit concerned because the model seems very lightly built compared to my Aeroworks and GP's Extras. It seems to me that it was designed leaning more for electrics than glow or gas. The fellow here that powered his with a .91 4-stroke could possibly let us know how his airframe is holding up. How about it LSP 972?
Karl