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
DVD Vol. 2 DVD Volume 2
This video is available on DVD

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

12/21 New Fork Instalation Dillema

I'm installing a new RST fork on my Schwinn Sidewinder, and I ran into a few problems today.
Steerer tubes on these forks are interchangeable, meaning that the tube is sold seprately, and installed by the customer.I chose a 160mm threaded steerer tube, because I wanted to keep the existing headset. I installed the steerer tube today without any problem, but when I went to put the new fork on the bike, I noticed two things: first that the new steerer is longer than the old one, and secondly that the crown race from the old fork doesn't seem to fit. The tube is mounted all the way onto the... Read more >>

11/22 How important is a keyed washer?

I'm going to be installing a new fork on a bike with a threaded headset, and the new steerer tube doesn't have a keyway, the way the old one did.
What's the better option, to cut a keyway into the steerer tube, or file off the tab on the keyed washer? Is there some other choice I haven't thought of?... Read more >>

11/07 Headset parts order


first post, but I have found a lot of good info on this site.

I have an old garry fisher Hoo Koo E Koo 1997/1998. The headset was missing the top seal part and I couldnt find a good replacement part. I found a cheap techno glide j-27 to replace the whole thing.

Now I have 2 problems.

1. I need a new crown race as the new headset uses sealed catr... Read more >>

11/03 Threaded headset to threadless

If I have a threaded headset with a 1-1/8" steerer tube, would I have to have the bearing cups on the frame replaced to use a threadless steerer tube?... Read more >>

08/29 Help with threaded stem

I brought a new 1" threaded rigid fork to replace old one. The Old fork tube diameter is 22.2mm, however I've just found out the new one has tube diameter of 21.1mm therefore my stem doesn't fit into the forks. Is there any way around this or do I need either a new stem or new set of forks again. I can return the forks as I I've scratched them when fitting the crown raceSad thanks. They are both 1", it's annoying as I assumed there was only one type of 1" threaded fork. Apparently the ... Read more >>

08/11 FSA Headset

I have a 2006 Bianchi 928 with a FSA Orbit ZS headset. I have a creaking sound coming from the head tube when I am out of the saddle and climbing. I replaced the headset parts other than the plastic cups that are pressed into the frame and the crown race which is pressed onto the fork. I have tightened the headset bolt up to almost 4 NM but I still have the creaking sound.

I cannot tell exactly where the creaking sound is coming from but I assume there is some play in the fork. When I turn the front wheel sideways and hold the brake on I can feel only a tiny bit of movement i... Read more >>

08/09 Headset/Stem confusion

I've recently rounded off a screw (pictured) and firstly I'm confused weather that part comes with my headset or my stem? Also can any headset fit with any stem?
I'm sure I could just buy a new screw but I'd rather buy a new headset.

If it helps I have a Social Narc 2013 bmx and the stem is a social freeloader it says the headset is just a "internal headset" now I don't know if that is internal the brand or how it's situated.

Any help would be great

Jordan...

07/22 42mm Inside Diameter Head Tube

Hi Everyone.
New to the forum.
I have an older dual suspension mountain bike, a giant ATX900. It has a weird head tube inside diameter of 42mm, which puts it somewhere in between the old 1 1/4" standard and the 1 1/2" standard.
Anyone know what type of head set was intended for this diameter head tube?
Cam...

07/01 Headset wont tighten

So I got a cheap bike from craigslist that I'm trying to fix up. The headset to this thing is really loose, if I lift the handle bars I can shake the whole fork easily. (Sorry if my terminology sounds retarded, I'm not super bike savvy)

I tried to loosen handle bars and tighten the bolt the youtube guy told me to tighten, with no luck. The bottom of the fork near tire seemed just fine, but the top still shook around. It almost seems like I'm just missing an important part. Im including pictures of it all put together, taken apart, and all the parts from the problem area. Because I... Read more >>

06/18 Won't come off


I am trying to remove a headset so I can service it but one part won't come off, I'm trying lubricating it and leaving it overnight. But I don't know if I should be trying to screw it off or trying to bang it off.

Any help would be appreciated!...

05/30 Headset into carbon

I have pressed headset bearings into steel frames many times, but in a couple of weeks I'll be doing it into carbon fiber - I do have the headset press in tools. In a video I watched, the guy checked the sizes with a digital Vernier gauge on the frame and the bearing piece - is this absolutely necessary? If so, does anyone know the tolerances for a light press fit? It'll save me looking it up in my old books.... Read more >>

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: bn9reqTl.jp...					<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, ill ... 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...

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