Hi Dick
I have been reading your post regarding the roto 25 i bought one in June this year when it came it had a carb that had the return blocked off,the engine did not perform very well, calling RCS they explained that it had the wrong carb on it and sent a new version it's the same one on my RCS 44 CC twin which runs very well replacing the carb on the 25 and adjusting the needles I found the running really improved i am spinning an 18x8 master airscrew prop the engine is on a hanger 9 edge planes really moves but i have a midrange cut out problem and if i adjust the carb so this does not occur i have no top end and the plane won't fly it almost stalls in the air have you had any similar conditions.

Rg's
Dennis