Now, as all right-thinking road cyclists know, fixies are the chosen steed of Satan. However, it's obviously a good thing if old bikes - sometimes, rather special ones - are used for riding rather than as a place for spiders to hang webs. So here we go...
Question: Can I adapt my old quill headset bike to accept a modern 1 1/8" (28.6mm) threadless stem?
Answer. Yep. And what's more, it's both easy and cheap to do so.
|The old quill-type 1" headset (left) has now been almost entirely replaced by the modern 1 1/8" headset.
As a result, choice of stems is now limited - and 1 1/8" stems are not compatible with 1" steerers. Unless,
that is, you use an adaptor.
All you need to do is work out what size steerer your bike uses, and the best way to find out is by measuring it with pair of vernier calipers. First, remove the existing stem by loosening the top bolt, which is often a 5mm allen bolt but may also be a hexagonal-head (or, if the bike is really old, a square-headed bolt - in which case, you should probably offer the bike to a museum). Once done, the handlebars and stem will come away from the frame - if they don't, the wedge nut that fastens them in place is probably rusted into the steerer. Freeing it will be a simple process if you read our guide on winter-proofing headsets.
|Quill system with lock nut removed to
show the steerer
(image credit: Ellywa CC BY-SA 3.0)
While you've got your spanners out, it seems silly not to take the opportunity to give the bearings a clean, replace any that are damaged or missing and relubricate the moving parts. In fact, this is especially the case if you're modifying an old bike because you may not know how long it's been since anybody last gave them any tender loving care. The winter-proofing headsets guide tells you how to do this.
Take a moment to check the internal condition of the steerer. Many are made of steel and may be rusty (especially if you had problems getting the wedge nut out): a good way to find out is to remove the front wheel and mudguard if one is fitted, then push a small piece of light-coloured rag through with a length of dowel or a broom handle - you'll be able to see rust on the rag. If it is, wrap some sandpaper around the dowel and give it a clean, then use a new piece of rag to remove bits of sand and then another to apply protective grease. Even if there is no rust, regrease the steerer anyway.
In Britain, they can be had from Halfords for a mere twelve quid: it looks - and we're trying to be charitable here - a bit spoddy, but it'll do the job. Our experience of Halfords is that some of their stores employ very good mechanics who know their trade and will immediately understand what you're looking for, then be more than happy to order one in if they don't have one. Other stores are, shall we say, not so good; and employ people who apparently know nothing about either bikes or customer service. Fortunately, if your local example falls into the latter category, you can also buy one online and they won't charge for p&p provided you don't mind waiting four days for it. Others are available, but do be careful not to accidentally buy a 1 1/8" steerer extender - the look very similar. If you're not sure, ask your local bike shop to order one in for you.
Clean and grease the threads of the steerer before replacing the lock nut, then adjust the system so that the steering turns easily and without any fore-and-aft or side-to-side rocking (there's more about that here). If you don't have experience in adjusting headsets, getting it just right can take a few attempts as there's a knack to be learned; but it's a simple process and you'll rapidly pick it up. Once done, you can fit the adaptor. These mimic the quill stem in having a wedge nut at the lower end, which causes the device to expand and thus locks it into the steerer - there are two types, both of which can be seen below.
|Wedge nuts, also known as expansion nuts. We prefer the type on the left, simply because it looks
less of a bodge, but they work equally as well.
Fix the handlebar into the stem, taking care to ensure it's centrally positioned (and, if it's a straight bar, the right way up - you wouldn't be the first to have put in the wrong way up). Sit astride the bike. Does the height feel right? If not, loosen the top bolt so that you can adjust the adaptor's position in the steerer. Once the height is ideal, tighten the top bolt to expand the wedge nut and fasten the adaptor in place. Sit astride the bike again to ensure then stem is in line with the front wheel. Once it is, fasten the bolts than pinch it onto the adaptor. Finallly, check you've tightened the handlebar clamp bolts sufficiently and the job, as they say, i a good 'un.