Rear Brake Hub

Hi - I'm new to the forum - and relatively new to Nortons, so bare with me.

I'm working on a '74 basket case and found two rear hubs among the debris. There's a number on the brake arm and I was wondering if that corresponds to a number somewhere else on the bike? This way, I might be able to detect which is the original. Also, anyone able to offer indtructions on how to open the hub?

Thanks!

Welcome to the forum lbm521.

The same basic rear hub and brake assembly was used from '71 through to the end of 850MkII/IIA production, if both assemblies look identical, then they probably are, so you could use either one, or use the best parts from both?

Useful info:
http://www.classicbike.biz/Norton/Repai ... mmando.pdf
http://www.oldbritts.com/nor_comm_73.html
http://www.oldbritts.com/1973_g20.html