I've always wanted a smaller converted engine, so I just finished doing one. The engine is an Echo 16cc that was originally made to run clockwise. Lefthand threads at the flywheel end were of little concern to me. I made an adapter for the 5/16" shaft and just recessed the nut below the adapter's mating face. Made the prop adapter to bolt onto it with 2 recessed 10-24 thread allen head capscrews. Worked out perfectly and very true running. Installed a new factory ring and converted the engine to CDI.

Performance is improving as the ring starts to break in. I am using a MAS 13-6 plastic prop that was carefully balanced. On the second 8 ounce tank of 32:1 Pennzoil and regular gas, I took some rpm readings with an Ace Optical tach and got a reliable 1600 rpm idle, followed by 7200 rpm top end. I am thinking it could gain maybe 500 rpm after some more running. Is 7200 a good starting figure for this lightweight engine?

Made a muffler for it from 1 inch square aluminum tube about 3 inches long, with a single exit stinger from 1/2" aluminum tubing. Inside the muffler, I drilled about 8 or so 1/8" holes to pass the exhaust thru. Drilled a hole in the side of the muffler for a retaining screw into the tubing locking it in place. I cut 2 end caps for the muffler from 1/4" 5 ply aircraft plywood. Retaing those in the ends with small sheet metal screws. After almost an hour's running time, it's still together and no noticeable leaks and is very quiet.

Pictures are in order when I get time. Using a C&H ignition with one of my autoadvance boards to give it a fighting chance. Hand starts in 2 or 3 flips. Can't ask for much more than that, and total cost was just for my time and a factory new ring. A Bowman ring will make it perfect.

John