Ok, I have found this for sale: YS120 supercharged 4-stroke with 3-blade prop, aluminum spinner and smoke muffler. Was purchased for use with Carl Goldberg Ultimate Bipe. Engine had a couple tanks of fuel ran through it for break-in about 10 years back but never got cleaned out after running, so it's a bit gummed up. Should be good as new with a thorough cleaning.

What are your thoughts on this engine, what would it be worth? I have seen pictures and I did not notice any damage. Thanks

Jon