I'm not sure I want to last another 40 years, being 67 later this year, I doubt if I could start it at that point, but then who knows, maybe the world's oldest Norton owner?
I think it is the original bearing. The only thing I see that involves any rebuilding is one of the bolts from the primary into the crank is a size larger than the others, but who knows, maybe that happened at the factory because they stripped it? As far as I know it had 4K on it when I got it and appeared to have been slightly abused, original clutch pack, looked like someone had busted a bit out of the timing cover and welded it, but ran like a freight train and pulled the blood out of your head, especially in 2nd gear from about 15mph to 70, love that broad torque band. It probably had been raced a bit.
Anyhow, there are 2 NJ306.M1.C3 bearings going back in as soon as I get the cases back from cleaning and I have the Norvil bottom end rebuild kit and new pistons, so I should be ready to go.
Dave
69S