33. How to Adjust a Threadless Headset

Learn how to check the adjustment of a threadless (Aheadset) and align the handlebars.

IMPORTANT: Nuts and bolts on your bike should always be tightened to the manufacturer's specifications.
How to Adjust a Threadless Headset
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In today’s tutorial, we’ll learn how to adjust a threadless headset, otherwise known as an ‘Aheadset. For this job, you’ll need either a 5mm or a 6mm allen key, depending on your stem.

To loosen the stem, simply turn the allen key on top counter-clockwise a few turns. Don’t remove it completely. Then loosen the two bolts on the side. Now your stem should turn freely.

To check if the headset is tight, lift the front of the bike off the ground. The handlebar should rotate freely and fall to one side or the other. If it doesn’t, you’ll have to loosen the top bolt a little bit and try it again.

To check for play, hold the front brake, place one hand on your headset, and rock the bike forward and backward. If the headset is loose you’ll feel it, and you’ll have to tighten the top bolt a little bit.

Once the adjustment is set, check the alignment. I find it easiest to line up the stem with the front wheel while you’re sitting on the bike. Once the handlebar is straight, tighten the two stem bolts and check the adjustment again just to be sure.


Related Links

Discuss this topic in the Headset Forums

03/20 What kind of headset and crownrace do I need?

advertised as 1 ⅛” headset. chinese carbon mountain bike frame on ebay. it has v brake tabs so i wouldnt' be surprise if it was a pretty old design. so do you think the fsas i linked above would work. Let me take some better pics.

here you go with some additional measurements.
[Image: mYFQhWWl.jpg]
cups are metal with black paint on them.
those numbers are 43.84mm, 35.05mm, and 8mm.

here's the fork
[Image: bn9req...					<a href=

01/03 What do i need for my headset?

[attachment=4796]I just got this bike and it needs work, the headset moves alot, i thought it was the bearings, it still might be, i cant see any, unless they are sealed? if they are sealed it seems everythings fine, though the gap from the forks to the stem is small so it wont lock all into place, making it move, i added a spacer but now the bolt will not reach the fork thread, the bolt is also slighty bent making it harder to tighten and work out whats up with it, do i need bearings? a new bolt? something completely different? im not very good with bearings at all so i need help please,... Read more >>

12/24 2 bearings?

Is there one or two bearings in this assembly? If there is two .... then im gonna need one. Elgin 1938. Does anyone by chance have any diagrams of the Elgin 37,38?
[Image: IMG_0360_zps9e5552a6.jpg]
Monk...

10/26 Folding bike headset question

Hi all

Thanks for taking the time to read this.

I just got my hands on a 2nd hand Dahon folding bike.

There seems to be a little play in the headset but as this is my first folder I'm not sure if this is inherent in folders or not.

Would anybody know if it is inherent and have any ideas on how to fix it? I have some experience of changing threadless headsets on mountain bikes but I'm not sure about folder headsets.

Thanks again

Ben...

07/11 Threaded or threadless?? what to go for??

I've acquired an old frame, I think early '80's Japanese or Taiwanese (thanks to nfmisso for his help there!) and I'm planning on building a single speed out of it. This is my first bike build so its a learning process for me, I'm pretty excited about the whole learning thing I must admit! I have a million and one questions to ask you bike guru's about bike building etc!
I plan on building the bike on a relatively low budget so I'll be looking on ebay for second hand parts etc. I want to keep the bike looking like an old bike not a new build where possible (as original as possible but n... Read more >>

06/13 Grinding headset

Hi; I just bought a used, rather nice Columbus frame to build a lightweight for my daughter. It has (had) a no-name roller- bearing headset which was decidedly crunchy, to the extent that when the forks were turned backwards it almost jammed. Also there is a half-ring patch of bare metal on the lower front of the steering tube ..... no sign of damage to the forks or frame, so I suspect poor installation of a worn headset and have bought another. Anyone else come across this type of uneven friction? Don't want to put out a bike with wonky steering!... Read more >>

05/19 Help to identify please

hi all,

my first post here.

i decided i needed a little project so i boughta 1968 Hercules with a 21" frame. it will be a surprise for my daughter.

I'd like to replace the parts shown in the pics with new ones. When i took it apart all the bearings fell out. i wonder if i could replace the bearings with caged ones?

what are the names of these parts please?


[attachment=4173]...

05/18 Headset bolt spinning in threadless headset


I'm new to the forum and need help. I bought a used year old Trek 7300 and then bought a headset extension to give me a more up right riding position. I'm 67 and bending over is no longer an option. Anyway to get to the point I installed the headset extension and after tightening the headset bolt there was still a little play in the headset. I'm pretty sure I tightened the headset bolt before the clamp bolts but after several attempts I can't say for sure I didn't forget something along the way as I said I'm 67. Anyway after several attempts I thought well maybe I just ne... Read more >>

04/12 Bearing question

Hi guys, I have a 2001 Gary Fisher Marlin. I took off the stem on my bike and didn't realize as the fork was loose the bearing fell out and broke. I'm not sure what size they are and the orientation it is suppose to be. The top bearing is still there. All i know is the bearing is in a retainer that is all. Any help would be amazing. Thanks... Read more >>

03/18 Headset bolt will not tighten - Schwinn Traveler

Hey there,

I'm trying to raise the handlebars on an old ladies Schwinn Traveler. I loosened the bolt to raise the handlebars, and once the handlebars are at the desired height the bolt will not tighten down anymore. I've been searching threads on here and learned there is a nut in the frame that I'm assuming I'm not catching anymore. Does anyone have any advice as to how I can raise the handlebars and still be able to tighten the bolt down? Or how to catch that nut so I can tighten the bolt? Any and all suggestions would be greatly appreciated. I will upload some pictures wh... Read more >>

03/11 Headset identification


Can anyone tell me what type of headset I have. If so any advise on how to service or videos on how to do so would be a great help.


Geoff...

01/14 Headsets

This may be a stupid question but I have read that headsets are not all that necessary for a build. Are they required or should I leave it out of the parts list completely?... Read more >>

01/10 Help with an vintage headset removal

Please Help! I'm trying to overhaul the headset on this old English roadster (circa. 1938-45) I'm at my wits end and I just can't get either the stem or fork out.

I loosened the stems tightning bolt and gave it a tap with the hammer. The wedge becomes and loose and drops into the head tube. However the stem won't even budge.

I can loosen the locknut but there is no hope of unthreading the adjusting race.

The tightening bolt is the only think I can remove.

I don't want to start tapping this with a hammer worrying that I coud be strippi... Read more >>

12/04 Loose steering


I have a road bike with a modern stem (threadless) & head set (1 1/8 size).

I bought it used and have been experiencing an awkard behave of my road bike in relation to steering: the steering seems rather loose.

I picked a 5mm allen key and tightened stem via clamp bolts and cap bolt. But the steering is very loose.

It comes more noticeable when pedaling with hands of handlebars or when holding the bike (and it keeps tumbling do... Read more >>

11/30 Spring loaded headset?

I wonder if anyone has ever come across a spring loaded headset. I just bought a Motobecane Grand Jubile and when I turn the handle bars it snaps into set positions. I assume it is spring loaded to do that. I've never seen anything like it and was wondering what the benefit is. I'm also about to refurbish the bike and I'm afraid of what I'm going to find if I take the headset and fork off.

Thanks!...

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