Hi guys, well the deed has been done and another waif and stray has turned up in my garage. As I anticipated I'm pretty sure it's going to need some attention. I am currently working on a B44 mongrel armed with the RR books and was wandering if there was something similar for the A50 / A65 twins. Or at least something that could be recommended that will make the rehoming somewhat easier.
I think the closest is probably Roy Bacon's BSA Twin Restoration.
I have found it invaluable. Admittedly I'm working on an A10, but the coverage of the unit engines looks as good.
https://www.amazon.co.uk/BSA-Twin-Restoration-Roy-Bacon/dp/0957066503
Adrian
The factory workshop manual is useful, comes in editions for 1962-65, 1966-68, 1969-70 and 1971. Add a parts book for your model and you are quite well equipped.
I agree with Julian, has all the info you need in there. Good luck.