Hello Geoff
I have reclaimed a set of Matchless G3L steering head races (1951) with a new set of balls and some fine valve grinding paste. I could not find any good ones at the time. This is about 20 years ago. I’m not sure what grade the grinding paste is. It is in a tube with course one end and fine the other. The fine is hopeless for removing pits in valves.
I just lightly squashed the assembly between the chuck and tailstock in my lathe, a drill press would work equally as well. I could hear it ‘growling’ when it started and the growl gradually went away. I would guess I used 300 RPM, lowest speed without engaging back gear on my lathe. I have done another set not long after then, probably for a 1954 MSS Velo. I can’t think of anything else that would have needed it. The Matchless has done about 100,000 miles since then and the Velo about 40,000 miles.
Geoff
