I am replacing the crankcase because they are damaged.
The new ones are stamped from 1957.
There seems to be a difference and I wonder if they are interchangeable.
The 1957 ones has a flat 'thrust' washer between the outer drive side ball bearing and case, but
the 1961 one has a something which comes through the casing, I have not taken it out to see if it is part of the bearing or a top hat like 'thrust' washer?
I have a picture of the 1961 one in the case.
Thanks
Matthew