Bicycle Mechanics - Headset Overhaul Question

mid-80's Miyata 912 that I'm completely overhauling. The lower head tube race clearly has to go and I'm planning of having my LBS do the R&R. Is it generally best to replace all the races and is it difficult to find parts that will fit my fork and head tube? Haven't measure the OD yet, but it's likely I'll just ask my LBS to order whatever I need if he doesn't have it in stock. Even though I have a new Giant OCR1 I'm really looking forward to having the old girl rolling again: good steel frame, triple chainring, 700c wheels, all Shimano 600.

It is usually best to replace a headset all together, unless you can find an exact match. The headset that will fit yours is almost certainly a very easy to find 1" English threaded headset.

I would just get a new headset. Shouldn't cost too much for a 1" threaded, and you'll have all new bearings and races.

That's what I figured. Thanks, guys. I don't have any idea how many miles I put on this bike, but the lower head tube race is really mauled. Probably doesn't help that it's not really sealed in any way.

Look into a Tange Levin. They come in 1" threaded. They are Campy copies from the same era. They last forever and won't brake the bank. A 912 Miyata deserves it. Nice machines.

Happy Trails!

Turns out the 912 has Italian threads (obsolete), but either JIS or ISO will work fine according to the Sheldon Brown application chart. This is a good practice run for getting my Wife's old 912 fixed up as well. Smaller frame, better condition.