Just an update on my Ryobi 31cc conversion. I worked on the reed valve and got it to seal off. I took and modified the original muffler. I removed the tube from inside the muffler and removed the little exhaust deflector. I drilled a 3/8" hole inside the muffler at the muffler inlet. I wanted to open the muffler as much as I can. I welded a 1/2" ID x 5/8" OD 3" long outlet tube. I pit the thing together with the modified muffler and ran it. I have a 16X8 Zinger Pro prop installed. I got about 7200 rpm and can now get the idle down to around 1900 rpm. I installed the muffler and blew into the exhaust to check for leaks as some said this could have been causing my high idle problem. The thing was sealed tight. This darn thing runs pretty sweet. Now to find a plane to put it in.
Thanks to everyone that helped.