I've just fitted a new rear master cylinder to a v65 but the lever isn't returning. I've replaced the bushes on the gear lever shaft so it is a little stiff but not so bad, and I'm sure it will loosen up.
Anyway, I've got a spring as per the pic, but this version of mcyl doesn't have a mount for the centre of the Spring. I seem to remember on an old v50 that the pivot that holds the lever extended by about 10mm on the right side as you look at the pic which is where the centre of the Spring was mounted.
I guess the question is can I get one of longer pins, which also needs to have the circlip ridge....?