I’d post full pictures of the frame you are referring to; there’s a ton of different frames out there and each one varies in form/function from the last. Maybe somebody has the same frame and can give you a picture of what it should look like? Otherwise kind of grasping at straws here…

Pictures say 1000 words, videos even better!

I know that frame, I used to have it; but sold it so I’m no help… everyone else may not have the frame memorized for a 33 year old Sankyo!