The Gilson 6 HP running at the Finch, Ontario show in June, 1990. We showed the engine at three shows last year.
Cylinder of 6 HP Gilson showing slats for connecting rod so it did not hit 11/4 deep and tapered back for 3 in. to nothing. Some years ago, I saw a 11/2 HP engine done the same way. I could not find the make of it.