Colnago Mexico Fork - Fitting a Campy Headset

I was trying to fit an Italian Threaded Campy SR headset onto the fork but it wouldn't fit.

Could the fork be French threaded? I bought the frame from ebay in the US. I tried the headset on a Reynolds fork and it fit perfect.

Another question is, the bottom of the Colnago fork has a slightly increased diameter and I cannot slight the fork race through, can anyone help. I am new to bike re-building.

It's very unlikely that the forks will be French standard, certainly Italian.

The three standards you are likely to encounter are ISO (British), Italian and JIS: ISO and JIS threads are the same and Italian threads are so similar, that in practice all three are interchangeable.

However, the internal diameter of the crown race differs across each standard: ISO is 26.4mm, Italian is 26.5mm or 27.0mm and JIS is 27.0mm.

If your headset screws onto the Reynolds forks but not the Colnago pair, then I suggest you clean out the Colnago's threads: if they have been damaged, then you may need to get them re-cut.

I guess your forks have a 27.0mm crown, but unfortunately you have a 26.5mm crown race: you could either widen the crown race with emery cloth etc, or get a race from a JIS headset.

Probably best to check with Vernier callipers first though.

I have inspected the thread on the Colnago fork and it looks fine. Yes, puzzling isn't it. I too don't think it would be french. Maybe I should go take a more detailed look at the thread, like you mentioned perhaps it got damaged during shipping.

Oh btw, my Reynolds 501 fork appears to have a fork race as part of the fork itself, is that common, and therefore I can use it instead of using the fork race from the headset?

Thank you.

Oh one more question, anyone can tell me where I can get paint to match: Saronni Red and Raleigh Team Red?

Can't say I've come across forks with an integrated crown race, but I'm far from an expert. Are you sure it's not just been painted over?

To answer your question, "yes" you can use races from one headset with another, provided they use the same type of bearing: ie you can't mix ball bearing, needle roller bearing or sealed bearing races.

A paint factor or bodyshop will be able to mix paint to match, but depending on how much you want this might prove expensive.