this was the 100" shovel i built for my club brother in 1980-- its had the trock 3 13/16th cylinders (look close you can see where the cases were welded) -- 4 3/8th stroke (unknown in 1980) -- the tom sifton special grind 468++ (280 duration instead of the normal 270) -- the old MGL side bowl -- custom tuned pipes -- i cut .100 off of the gasket surface and welded a blob of aluminum on 1 side of the cumbustion chamber to make a swirl type cubustion chamber -- cylinders were .235 taller -- 24 motor -- 22 tranny -- 46 rear -- bike wasnt a redlight racer by figuring the gear ratio/tire diameter/rpm it would run 147mph -- in 1980 this was FAST!!