You are correct, they are indeed Canned Hams, well done. The top and bottom are a 250, the one in the middle is a 175. I have 6 Canned Hams of various models a '69 Yamaha AT-1 125 and a '79 Maico 440.
I was leading the national championship points for 200 Expert in cross country until a couple of weeks ago when I choked and gave away two races to my nemesis. I crashed while leading both races fairly comfortably.