Rear brake plate: what year did it change?

For the 88 and 99 models it was 56 and I believe it could have been May 56 when they also dropped the pear drop silencers, laydown box etc but I guess it could have been the end of the year when they also changed the front wheel , rear mudguard lip, tank etc.

There are 3 types of swinging arm around this period, 55 has the rear wheel slots pressed out of the tubing. 56 models (mines a jan 56 has cast rear wheel lugs but the old brake arm and Chainguard with the flat brackets on top (early type). Then there was the later ones with the slot for the brake plate and the later Chainguard which may have been later in 56 for the 57 models. 56 twins went through a lot of changes over the year as I found out.

i have a 57 inter and that has the older style but they did build them to older specs generally but that's a different story.

i had all three laid out when I was building my 56 and wondered why so many...

I'm not sure if this carries to singles?

hope this helps

Mark