I recently bought a frame and fork (separately) on eBay, and now it's time to get a headset (all the other parts but that and seatpost I have had for a while waiting for a frame).

Based on seller measurements (and pictures one sent of the part with a ruler), the headtube of the frame is 200 mm and the stem has a ~240 mm steerer. Obviously, I'll be verifying the measurements myself when they arrive, but it seems that, with a shorter headset, they should work.

So on to my million and one questions.

1) Some headsets list stack and stack height as two different numbers. I'd been figuring (and someone confirmed to me in a different thread) that my steerer needed to be the height of my head tube plus the stack height of the headset (maybe plus 3mm for a lock washer that might not be included in stack height), or, to put it another way, the maximum stack height I could use would be steerer tube length minus head tube length (so, in my case, that's 240 mm-200 mm = 40 mm). But then I see a number of headsets that have two different numbers. Off the top of my head is the Campagnolo Record and the apparent Tange Levin clone that have a stack of 35.6 mm and a stack height of 38.4 mm (or something close to those numbers). Which of those is the number I need to be concerned about when comparing to the difference between my steerer tube and head tube lengths?

2) Also where does the lower cup stack that some places like Velo-Orange list fit in, do I have to add that in to the stack height too to get something maybe 11 mm more? I hadn't seen that measurement before and hadn't figured it into my needs when buying the fork.

3) Because I mentioned the Campagnolo Record headset and the Tange Levin one above that have the same measurements, is the Campagnolo one significantly better than the Tange one? The Tange can be had for ~$30-40 whereas the Campagnolo one is more like $80-100. Is the only real difference the logo? The rest of the parts on the bike (other than the seatpost, which will be the velo orange knock off of the nitto dynamic) are going to be campy, so I can see paying a small premium for matching, but I'm also cheap, so I'd like to know there's a reason other than vanity as well. Otherwise, it'll make justifying the extra $50 harder.

4) What about the whole ball bearing vs needle bearing thing? I know some people really liked the old Stronglight A9 saying it was longer lasting and better than most ball bearing ones, and Velo Orange and Miche (maybe Rivendell too) do still sell headsets with needle bearings instead of ball bearings. Are they worth looking into? Or is it better to stick with the standard of ball bearing headsets figuring they're the standard for a reason?

5) Should I look at cartridge bearing headsets instead? I've heard from a lot of people that seem to like the Grand Cru one, but at 43 mm stack height, that sounds like it might be a smidge too tall to work in this application.

6) Finally, and not really related to headsets, the fork is a Tange steel and there is a code on the steerer tube (4J). Does that mean anything? Tell what kind of tubing it was? Just sort of curious. I won't be looking for decals for it as the frame is SLX (this was the only fork that was relatively the right length, looked like a good match, and was in the price range I wanted to spend that I could easily find) and I don't feel like having non-matching stickers on there to make it obvious that it's a replacement.

I like the Tange Levin HS a lot and think it's a great value.

The VO needle bearing HS ime feels like it has a lot of pre-load when you take out the slop. Maybe that's just the way NB headsets always are; I don't know.

As far as any of the VO choices, you should be able to email them directly if you have any question about one of theirs fitting your frame/fork.

Ha ha, I thought I could do the same thing with my VO headset- take it out and replace it. Easy right?

But no.

Take it into the shop, they need headset pullers, and pushers to put the new one in they may have to face (cut) the headtube to get level, they are doing this in thousands of an inch.

I got a hammer and a punch, what do you think my chances of success are? All in all, a big deal for you to screw up, and a simple job of a LBS.
Chances are the headset is fine for your bike- stop micromanaging.

Just take it in. This is what I am doing as screwing it up can wreck the headset and the frame not worth saving the 40-50 bucks.

Well this one doesn't have a headset on it and I do have a headset cup press that I bought for less than it would cost to have some pressed in at my last lbs (recently moved). Got the "rocket" to get the cups out for less than they charged me last time too. Don't have a tool to get crown races off, but fortunately that's not an issue here.

Roller bearing headsets always have more rotational friction than balls; the increased contact area that allows them to deal with thrust loads better than balls comes at the cost of more friction. But since unlike e.g. hubs or bottom brackets, headsets are not in constant rotation when in use, this additional friction is irrelevant. I have both ball and roller bearing headsets on my bikes and can't tell any difference when riding.

In my experience, roller bearings last longer without pitting than ball bearings.

A nuovo record headset has a total stack of close to 40mm. Since you have 40mm you have nothing to worry about. You can use almost any headset you want and add spacers if you need them. 40mm is on the higher side for stack.

The lower cup stack is important for frame builders so when the design the bike they know how much height to add between the steartube and the fork crown in order to preserve the exact geometry they want. In practice many frame builders will just use a nominal number like 13mm as one or two does not make a difference anyone can see or feel. But in the current era of ultra precision anal retentiveness people want to build to an exact dimension. I.e. forget about lower stack height, it is not important, you only need to be concerned with overall stack height which will usually be in the high 30s to 40mm.

In terms of functionality it is not worth the premium for the campy. Cartridge bearings are better because the cups will never wear out like a traditional headset, but a good headset lasts a very long time and if you ride your bike enough to wear out a tange levin than your drivetrain will have been replaced many times over and you will likely have repainted your frame at least once. I wouldn't spring for campy since the frame and fork are mismatched and it sounds like this is a rider, not a show bike. I would buy the headset with the look you like the best.

The 4J on your fork is probably a date code. I wouldn't think about it too much, just put it on and ride.

Thanks for all the advice. Yeah, this will definitely be a rider. Hopefully, it'll be a nice rider (as in give a good ride), but this is for me to ride. It'd be nice if it looked cool-ish, but it's not going to ever be a museum piece. I have an additional question:

What's this about English vs. Italian threading when it comes to forks/headsets? Sheldon's site says they're both 24 tpi, and there are some headsets that say they're for either type of fork, but others say that they're specifically for one or the other (and most don't say anything at all). Does it really matter? Are they really interchangeable for my purposes?

Well, you got it as a frame and loose fork, so you don't know what it has been fitted with. The difference is the inclusive angle of the thread profile, one is 55° the other is 60°, there is a difference but if you think about it not much. I forget actually which one is which. It was pretty typical to sub an English headset on an Italian bike, Italian headsets were just not as easy to get long ago. A class "B" fit, but functional.

If you can get the correct threading, do so. But do not lose sleep over it.

I like Campagnolo, but the Tange is quite good, from your description of your project run with that.

Do have it installed with a real tool though.

Ditto to both points. I had a "cartridge bearing" headset that developed play between the bearing and the headset cup that manifested as a rhythmic squeak while riding. That sucked, because otherwise the headset was perfect. I replaced it with a Tange Levin a couple years ago and it's been perfect.

You know, it just occurred to me that I think I have an old DA 7200 (or maybe 7400?) headset (used not new, but, if memory serves the races and balls looked smooth) in the back of a box somewhere that I'd set aside for a project I'm not sure I'll ever get to. Maybe I should just use that and save myself even more now and worry about what to use on that other project if I ever pick it up again. No idea on the stack height for that, but I suppose I can try it and see.

Since the fork is Tange and not Italian, is it fairly safe to assume that it'll be English thread? Given that the frame is Italian from the late 80's/early 90's, I would probably expect the original for to have been Italian threaded like the BB, but, because the replacement is a Tange fork of unknown vintage (the seller told me it was 26.4 mm crown race - at least he was pretty sure and if, not I'll see about getting it milled - but didn't know what bike it would have come from), my only point of reference is that it's of Japanese make and I thought that might make it more likely to be English, but I really don't know why I thought that. I suppose it doesn't really matter.
I do have an unused headset press and tool for pounding on the fork crown race, both of which I found on good sales over the last year or two because I now have 3 or so projects in various stages of completion and I figured at the point of two or more buying the tools (in addition to being a better learning experience) was cheaper than paying to have someone do it for me.