Hello,
Just thought i`d give brief rundown on my 120 Fourstar with the 31cc Ryobi. Great combo in my opinion! for anyone looking for a plane to put the Ryobi in. The plane came out just a tad over 13lbs. Moved the firewall back about 1.5", put servos in tail, still had to add little tail weight. Its a 31cc 2ring engine, so far been getting around 7,800 rpm with an APC 18x6W. Excellent verticall perfomance, was pleasntly suprised. I used the Paragon conversion kit, except for the muffler which is from Bennet. I used the primer bulb and choke, but dont think the primer is necassary. It does need to be spun over fast to start though. With a fast spinning starter it starts imediately. Has been super reliable so far, and excellent idle. I only put a 14oz. tank in it, but will run forever. I think glow powered planes are becomming a thing of the past for me Love the cheap reliable gasoline powerd engines.

Gregg