I think I should buy a jewellers loupe, to see close-up of bearing surfaces.
I have been rebuilding my own bigend end bearings for M and B series with good results, I think!
Also trying to source NOS WLA flywheel shafts, where the rollers run direct on the shafts.
Bloody hard to find items like ebay #201062477045.
How much has the oxidization degraded the surface, in particular Harley flathead parts that run 10ths of a thou.
Some parts you buy BSA or Harley are packaged greased in a plastic or paper bag, where over 70 years, moisture has found its way in, and the result is the blackened finish.
A clean up with 2000 grit emery is good, but very easy to take off too much, and make a part out of round if not careful.
KeithA

email (option): keithatkinson@hotmail.com

Yes, this is always a risk with NOS packaged components...I guess that's why the sellers don't remove the packaging themselves... ..

I've had a few disappointing and expensive examples over the years...Most recently I bought a big end that turned out to be unserviceable...

The 'tropical' packaging was designed to protect the parts in high humidity climates, but damage to the outer packaging over 70 years or so and the drying up and failure of the inner layers mean, unfortunately, you don't always get what you expect...

Without X ray vision the only thing you can do is examine the outer layers very closely for signs of damage/failure and look out for signs of 'rust staining'...

Plenty of BSA parts are also toleranced to 10ths of a thou by the way!..Ian

email (option): ian@wright52.plus.com