One side of my main wheel 600x6 (3600# gross wt. TwinCo.) has a race which I can move by hand. I am assuming that I will need a replacement wheel half. I will see my IA tomorrow.
Where would the "smart money" be spent? I see the options as a new or used half, or a new or use complete wheel.
What would make a race slip? The bearings and wheel looks in very good shape, it is only the race that can move though the race itself is not scored, etc.

Thanks for any education and advice you can offer.

there are several fixes for this that we have used over the years on machinery. Peening the ID of the wheel with a punch, followed by using Loctite bearing mount is very effective. Is it legal? no idea

Maybe a new race would press in, but the "land" is probably buggered now.
A new wheel is probably the fastest way to just put this behind you.

I would guess the most likely thing to cause a loose race would be the wheel nut being too loose for a long time.
If the race was still tight enough I might try LocTite bearing retainer, or Belzona and keep a eye on it.
Best solution is probably by a good use wheel, should be plenty available for a Twinco.

Greg