Friday, April 1, 2016

The New Old Bike Project: Headsets

I've written quite a bit in the past about some of the components from Specialized in the '80s. Most of the parts were really well made and offered a good value at the time. One of those parts was the sealed headset, which I believe was made to Specialized's design by Tange Sekei. With rubber o-rings and a special channel-seal design, it was a unique piece. They were available in both steel and aluminum versions.

An ad from 1985 features a cutaway view revealing the o-ring channels.
The Specialized Expedition I've begun renovating came equipped with a couple of Specialized's own branded parts, including the steel channel-sealed headset. Despite 30+ years of use, I pulled this off the frame and found it to be in remarkably good condition. Once it was cleaned up, I could see that the bearings and races were still in great shape - ready for many more years of use. The chromed steel finish on the outside had developed a faint rusty tarnish, but that cleaned off easily with nothing more than a bit of metal polish.

Specialized channel-seal headsets from the early 1980s. The steel version is on the left, and the aluminum version is on the right. Both have steel bearing races and rubber o-rings that snap into a channel in the cups. The aluminum version has thicker cups and a slightly taller stack height than the steel -- a couple millimeters or so.
Not only do I have the steel version, but as the pictures show I have an aluminum one as well. The aluminum one came off another old bike I had done some work on a few years ago. It was covered in so much grime that I'm not sure I even realized at first what it was. After I cleaned it up, I discovered that it was in good condition and I was super pleased to discover what a nice piece I had. It had some visible wear in the races, but nothing excessive. I set it aside for another day.
Apart from the bearings, it doesn't appear to me that the internal pieces would be exactly interchangeable between the steel and aluminum versions. On the aluminum headset, the fork crown race, as well as the top head-tube race are slightly thicker to account for the taller, thicker aluminum cups. In this photo, you can just about see the tiny channel around the inside rim of the aluminum cups -- the o-rings snap into those.
With the Expedition project, I thought about using the aluminum model headset, but ultimately I decided against it. The stack height is just a bit taller -- it would probably work but it would be close, and I wouldn't be comfortable having the aluminum top locknut only engaging a thread or two. As was done so often back in the day, the Expedition was built up with its stock headset, including a single keyed washer, and no extra spacers -- then the steerer tube was cut to fit exactly. I find that a lot when fixing up old bikes. It's as if nobody could ever imagine needing (or wanting) to change a headset someday, or using a headset that might possibly have a taller stack height. No big deal -- the steel one will work great, and I know it fits perfectly. The aluminum one will just wait for the right bike to come along.

These headsets come up on eBay from time to time, and they sell for more money than one might expect. At a time when one can still find brand new 1" threaded headsets for about $20 -- units that look similar to these vintage ones but without the seals -- it's not unusual to see these Specialized sealed headsets selling for $50 or more for used examples. A lot of money for a used headset, to be sure, but it's a testament to their quality and longevity.

6 comments:

  1. I find this situation a lot too when working over older low or mid grade bikes. It seems that many were all fitted for the ubiquitous Tange Levin which has a pretty short stack height. Often it would be nice to replace the headset with something nicer like the current offerings from VO, but there simply isn't enough room. Fortunatly the old Levin is still available. Harris and others still stock it. I find myself thinking would it have killed them to throw a couple of spacers in there.

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    1. Any time I'm building up a new bike, if I have any choice in the matter at all, I always like to leave the steerer longer than needed, and use some extra spacers. Adding spacers is cheap. Once the steerer is cut, there's no going back. And yes, there are still lots of low-stack steel headsets out there, and luckily they're cheap.

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    2. When I bought my green Mercian mixte a few years ago, the headset--a Shimano model similar to the ones made by Tange--was in rough shape. Whoever assembled the bike cut the steerer tube to use the headset with an old-style centerpull cable hanger (the bike has cantilevers), which takes up even less space than most headset spacers. On top of that, Shimano's stack heights are lower than those of most other headsets.

      I probably could have replaced that headset with a Tange--or, of course, another Shimano. But I found that I was able to use a Chris King headset I'd saved from another bike. It's the one on which the top locknut and top adjustable cup are separate pieces, as they are on traditional headsets. (Another King headset has an integrated locknut and top race, which has a larger stack height.) I used cable hanger that attaches to the stem, and everything has been working well for the past four years. Still, I wish that the steer tube had been cut a bit longer!

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    3. On some bikes where it's desirable to keep the original fork I've even had the harebrained idea of cutting off the original threaded section and brazing in a longer replacement piece. The new piece could then be re-threaded. I'm a machinist by profession so the machining and brazing isn't that intimidating but I'm a little wary of the strength of the final product. I can see myself riding down the road feeling quite smug and clever only to end up in the ditch with a fork blade stuck through my head. Nevertheless back in the good old days when people had more time than money you know some old coot tried this.

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  2. Perhaps I’ve sucked down a little too much of Grant Petersen’s Kool-Aid (really tasty, by the way), but when I finally bit the bullet and had my custom bike built I specified a Tange headset that uses a combination of ball bearings (top) and needle bearings (bottom). It looks and feels great, and my hope is that I’ll never have to replace it.

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    1. I know that headset - and I'm sure you'll get many, many miles out of it. I may have mentioned it in another post, long ago, in reference to needle bearing headsets. I like needle bearing headsets generally, and that one you've got combines the best of both worlds.

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