Tell me about threadless headsets

[Toady]

Part N in a continuing series as I struggle to enter the 21st century.

As I understand it, which could be totally wrong ... With a threadless headset it's very hard to adjust the height of your bars unless you either (a) leave a big part of the steerer uncut, and even then you have to readjust the bearings when you want to move the stem up or down and swap spacers, or (b) fit an articulated stem that will change the reach at the same time as changing the height or (c) fit a headset extending column (I've not looked into these).

Now, I see that as a big backward step from a quill stem.  Say I get a bike with a threadless headset and then do my back in, or get a bit older, or change my mind about my ideal riding position.  Instead of just a 30 second adjustment, I'd be faced with buying new stuff and/or significant fettling.  And if a bike with a threadless headset is bought second hand, the buyer is able to adjust the saddle but is relatively stuck with the bar height.  Izzat so?

I take it that the type of headset is actually dictated by the forks - with modern forks not having threads.  Is that right?  And do modern head tubes only accept threadless headsets?  So if getting a modern bike, a threaded headset is not really an option.

They seem like a really bad idea to me, but one that is unavoidable if using modern stuff.  Not to mention the fact that they are ugly as sin, and a nice quill stem is a thing of beauty.  Do they have anything going for them that I'm missing?  If I get a modern bike am I doomed to compromising my ability to adjust/tweak my bar height?

Or have I got it all wrong, as is so often the case?

[Cudzoziemiec]

A quill stem can be a thing of beauty but the three in this house are ugly, whereas the one threadless stem is middling pretty.

If you want to change the reach as opposed to the height, isn't it easier to change a threadless stem than to remove a quill stem and fit a new one?

As for the technical bits - I'm not sure!

[Toady]

A quill stem can be a thing of beauty but the three in this house are ugly, whereas the one threadless stem is middling pretty.

If you want to change the reach as opposed to the height, isn't it easier to change a threadless stem than to remove a quill stem and fit a new one?As for the technical bits - I'm not sure!

Possibly.  I'm not sure.

I've re-read my post and it does rather come over as a threaded vs threadless "which is better" rant, which wasn't the original intention.  That was just me being blindly reactionary.   (Edit.  OK, it is a rant.  But only because I'm baffled by new(ish) technology.)

I do genuinely need/want to understand these newfangled threadless thingies. 

[andrew_s]

Most quill stems only give 2 or 3 inches of height adjustment before you start flirting with the limit mark.
A threadless stem with an inch or so of spacers and the option of turning it over so it angles up rather than down can match this.

A threadless stem is generally lighter and stiffer (not that I care much about this).
Quill stems are prone to seizing into the steerer tube if neglected for too long - check out the number of threads asking how to extract a seized stem for evidence.
Threadless stems almost always come with a removable bar clamp, quill stems rarely do.
Threadless headsets can be adjusted with an allen key rather than 2 whacking big 32mm spanners.

Practicality beats looks any time, IMO.

[rafletcher]

Part N in a continuing series as I struggle to enter the 21st century.

As I understand it, which could be totally wrong ... With a threadless headset it's very hard to adjust the height of your bars unless you either (a) leave a big part of the steerer uncut, and even then you have to readjust the bearings when you want to move the stem up or down and swap spacers, or (b) fit an articulated stem that will change the reach at the same time as changing the height or (c) fit a headset extending column (I've not looked into these).

Now, I see that as a big backward step from a quill stem.  Say I get a bike with a threadless headset and then do my back in, or get a bit older, or change my mind about my ideal riding position.  Instead of just a 30 second adjustment, I'd be faced with buying new stuff and/or significant fettling.  And if a bike with a threadless headset is bought second hand, the buyer is able to adjust the saddle but is relatively stuck with the bar height.  Izzat so?

I take it that the type of headset is actually dictated by the forks - with modern forks not having threads.  Is that right?  And do modern head tubes only accept threadless headsets?  So if getting a modern bike, a threaded headset is not really an option.

They seem like a really bad idea to me, but one that is unavoidable if using modern stuff.  Not to mention the fact that they are ugly as sin, and a nice quill stem is a thing of beauty.  Do they have anything going for them that I'm missing?  If I get a modern bike am I doomed to compromising my ability to adjust/tweak my bar height?

Or have I got it all wrong, as is so often the case?

Essentially you're correct. The height of the stem (forward projection) with a threadless heaset is governed by spacers below (and sometimes above) the stem at the point it clamps to the (unthreaded) steerer tube. So, not easy to adjust on the fly for a bad back - though fitting a stem with less reach / more rise could be done relatively quickly (if you had one handy!)

If you have  threaded steerer you can get an "aghead adaptor" - basically the vertical part only. with a quill type fixing for 1" steerer tubes and 1 1/8" top section to take modern "ahead" stems. See below.

http://www.probikekit.co.uk/bicycle-handlebars-stems/deda-spada-quill-stem-adaptor/10770284.html?utm_source=googleprod&utm_medium=cpc&utm_campaign=gp_sports&affil=thggpsad&&affil=thgppc&gclid=CIa5qO-CoLkCFatj7Aodiy4AYQ

As to suitability / sensibleness, well progress is progress, and most modern bike design progress seems to be race-technology lead.

Modern headtubes will accept threaded headsets (they're generally just a tube after all)- the bearings press fit just like usual in those that do (though frames built for "hiddensets" have specially machined recesses for particular types of headset). The thing you won't find easily is threaded steerers at 1 1/8" - most modern frames have 1 1/8" head tubes, (most have alu or carbon steerer tubes so not suitable for threaded headsets - well Alu not IMO and carbon definitely not).

As to aesthetics, I like mine, though it's arguably less elegant than the 3TTT quill I had 20 years ago.

[rafletcher]

Quill stems are prone to seizing into the steerer tube if neglected for too long - check out the number of threads asking how to extract a seized stem for evidence.

Indeed - my last one (when I tried to remove it after purchasing a bike) took a LOT of percussive maintenance to shift it - with a 6lb lump hammer and a block of wood.

[Cudzoziemiec]

Modern headtubes will accept threaded headsets (they're generally just a tube after all)- the bearings press fit just like usual in those that do (though frames built for "hiddensets" have specially machined recesses for particular types of headset). The thing you won't find easily is threaded steerers at 1 1/8" - most modern frames have 1 1/8" head tubes, (most have alu or carbon steerer tubes so not suitable for threaded headsets - well Alu not IMO and carbon definitely not).

My alu-framed hybrid, which dates from 1998, was designed with a 1 1/8" threaded steerer. When I decided to replace the (minimalistically suspended) forks with rigid ones though, all I could find to fit was a steel fork (which I still haven't fitted), so there are some threaded threaded steerers at this size, but not many and I think most are for mtbs with 26" wheels (my hybrid has 700c).

[rafletcher]

Granted I was thinking only of road bikes in my reply. 

[zigzag]

threadless headsets/stems are light, stiff and don't require special spanners to install and adjust them. if you have the bike of the right size initially, you will not need to worry about adjusting handlebars - well, you can flip the stem up or down to switch between racier and more upright positions (takes only few minutes). quill stems look more elegant on the right (i.e. old school) bike, but they are heavier and flex too much when riding out of saddle. also quill stems do not come for 31.8mm diameter handlebars, which are superior imo.

[Toady]

Thanks all.  I wish I hadn't worded my original post so negatively.  I want to embrace new technology, I really do.  Honest. 

I'm in the process of getting a new bike, with all kinds of strange new things like STIs and a sloping crossbar and stuff like that ... and a funny headset.   I'll be down wit da kids in no time.

I know my current set up, and that suits me fine at the moment.  So I'm going to ask the vendor to provide me with a steerer that's a just a bit higher than than that, to allow me to change my mind a bit upwards as well as downwards.   

[Biggsy]

Now, I see that as a big backward step from a quill stem.  Say I get a bike with a threadless headset and then do my back in, or get a bit older, or change my mind about my ideal riding position.  Instead of just a 30 second adjustment, I'd be faced with buying new stuff and/or significant fettling.

It's enough fettling to be annoying, but it can be done quite quickly.  I've even done it by the roadside.  All you need is one or two allen keys.  2 mm spacers are available to help with fine tuning.

And if a bike with a threadless headset is bought second hand, the buyer is able to adjust the saddle but is relatively stuck with the bar height.  Izzat so?

Yes you're more limited, though you can change the stem for one with more rise or change the forks.

I agree that threadless is a step backwards, but it's also several steps forwards (steps explained by the posters above).  Another advantage of threadless is that it makes forks cheaper and more versatile than they would be otherwise.  The makers and sellers need only one size to fit all.  It's easy to cut down to suit.  Regarding appearance, threadless stems look ugly, but integrated threadless headsets look very sleek indeed (not that integrated is universal yet).

Anyway, don't be put off modern bikes because of this.  You can request uncut or long steerers with some new bikes, or eventually find/make what you want from the second-hand market.

[Toady]

The makers and sellers need only one size to fit all. 

Ah ha. I think I see the reason they have been so successful!

I'm just scared that I'll make a mistake in specifying my new bike, and shell out a load of money on a bike that has bars too low and can't be adjusted up.  Cutting a steerer is a bit of a no-return process.  Just need to be double sure the vendor has all my required measurements both verbally when I test ride, and on email/paper.  Being quite tall (I ride a 25" frame at the mo) these may a bit out of the ordinary.

[The French Tandem]

If i were living near your hometown, I would happily lend you the two dozens or so of stems of various length and angles I have accumulated over the years, for you to try and find what is best for you. Someone near you certainly have such a pile of bike parts, just ask!

[Polar Bear]

Ask for an uncut steerer with your new machine.   This will allow you to experiment with stem position before getting your LBS to cut off the excess when you're certain that you know the highest point you need for a stem.   I have extra steerer above my stem anyway as I have a Thorn accessory bar mounted above the stem.   

Almost all ahead stems can be mounted pointing up or down so this allows for quite a range between a sportier position and a relaxed position simply by flipping the stem.   You can also buy a gizmo which replaces a spacer in the stack below the stem and grips to the steerer thus maintaining the preload on the headset and removing the worry about getting the adjustment right every time.   

[Biggsy]

(Cross post with PB)

You don't have to cut the steerer down to the final length in one operation.  You can have lots of above the stem to begin with, and trim it down further later, still leaving a spacer deep enough for future tuning if you like.  This is unfashionable, but perfectly practicable.

Just ask the bike shop to supply the bike with uncut forks, or build the whole bike yourself.  The steerer is usually aluminium or carbon these days, easily cut with a junior hacksaw.

[Toady]

Just ask the bike shop to supply the bike with uncut forks, or build the whole bike yourself.  The steerer is usually aluminium or carbon these days, easily cut with a junior hacksaw.

I was going to do this, but after several months with no bike magically appearing I decided that it wasn't going to happen.  I'm not going to find the time/inclination for a big project.  So I'm actually going to buy a new bike  (from Spa).  Something I've never done before.  And if I'm going to pay for the luxury of a proper bike built by people who actually know what they're doing, rather than a rattly bodged thing, I want to get it right, and don't want to spoil the experience by bodging it myself.  Not at first anyway.

[Kim]

Straight tradeoff of long-term adjustability for reliability and ease of servicing the headset.  Whether that's a good thing or not probably depends on the bike in question...

[velosam]

I think you should be OK then, just ask them to leave the max amount of safe steerer and run more spacers.