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View Full Version : First Foray Into Threaded Headset Adjustment Gone Wrong


grognaak
08-28-2019, 11:11 AM
So, I noticed a knocking when using the front brake. Diagnosed as headset problem and ordered the Park Tool wrenches--fine, everything normal so far. I proceeded to scratch the hell out of the Campy Record headset trying to adjust it, had to go back and forth trying to find the proper tightness way too many times, had no idea how tight to go on the locknut, and ended up scratching paint from the frame when the front brake slammed into downtube. :eek: This in spite of watching several YouTube videos and reading Zinn several times. I don't think I went too far tightening the race, but I'm not sure. The front wheel seems to turn pretty easily and the knocking is gone when the brake is held, but . . .

I'm left wondering . . .

How do I avoid scratching the hell out of the headset? If the wheel doesn't return perfectly to center when pulled to the left but goes a little past center and sticks there when the bike is held up and tilted forward, did I screw up the headset? How tight is the locknut supposed to be? Is it easy to screw up something up by going too hard on the locknut? Can a steel frame be damaged or is it limited to the headset if you have fists of ham? Should I use nail polish to touch up the frame?

Thanks!

Mark McM
08-28-2019, 12:41 PM
I have to admit that I often end up marring the faces of the locknut a little bit when I adjust the headset, but I find that better quality tools are better in this regard.

Obviously you don't want the headset to be too loose or too tight. You want a little bit of preload on the bearings, but the headset should be free to turn. For too loose, I lift the bike up by the fork drop outs so that the weight is balanced completely on the rear wheel. I then apply and up and down force on the dropouts and feel for any looseness or play. If any play is felt, the bearings are too loose. This test is potentially better than "lock the front brake and rocking the bike forward and back" test, because it eliminates any flex and play in the brake and front hub bearings.

For too loose, lift the bike straight up vertically (both wheels an equal distance off the ground), and gently tilt the bike to the left and right a few degrees. The fork should readily turn in response to even the smallest change in the tilt of the bike. If a large change in tilt is required for the fork to turn, the bearings are too tight.

There could be several reasons that the steering angle of the fork is biased to one side when the bike is perfectly vertical (not tilted to one side or other). The most common cause a little stiffness in the brake/derailleur cables. If the bias angle is small, and if the fork easily turns (in either direction) when the bike is tilted to the side, then this should not be a problem. If the bias angle is large, then you'll probably want to address the length/routing of the cables. Another possible cause is an notched headset (and that the notches are off-center). In this case, you can usually feel for the presence of notches by gently turning the fork by hand. Typically, there will be several notches, equal distant apart. A notched headset should be replaced. A further possible cause is a poorly faced head tube, causing the top and bottom races to be non-parallel. This can be detected by rotating the fork completely around, and noting if bearings get tighter or looser at different orientations. If the bearing preload changes as the headset is rotated, the headtube should be faced.

Ken Robb
08-28-2019, 01:16 PM
I have to admit that I often end up marring the faces of the locknut a little bit when I adjust the headset, but I find that better quality tools are better in this regard.

Obviously you don't want the headset to be too loose or too tight. You want a little bit of preload on the bearings, but the headset should be free to turn. For too loose, I lift the bike up by the fork drop outs so that the weight is balanced completely on the rear wheel. I then apply and up and down force on the dropouts and feel for any looseness or play. If any play is felt, the bearings are too loose. This test is potentially better than "lock the front brake and rocking the bike forward and back" test, because it eliminates any flex and play in the brake and front hub bearings.

For too loose, lift the bike straight up vertically (both wheels an equal distance off the ground), and gently tilt the bike to the left and right a few degrees. The fork should readily turn in response to even the smallest change in the tilt of the bike. If a large change in tilt is required for the fork to turn, the bearings are too tight.

There could be several reasons that the steering angle of the fork is biased to one side when the bike is perfectly vertical (not tilted to one side or other). The most common cause a little stiffness in the brake/derailleur cables. If the bias angle is small, and if the fork easily turns (in either direction) when the bike is tilted to the side, then this should not be a problem. If the bias angle is large, then you'll probably want to address the length/routing of the cables. Another possible cause is an notched headset (and that the notches are off-center). In this case, you can usually feel for the presence of notches by gently turning the fork by hand. Typically, there will be several notches, equal distant apart. A notched headset should be replaced. A further possible cause is a poorly faced head tube, causing the top and bottom races to be non-parallel. This can be detected by rotating the fork completely around, and noting if bearings get tighter or looser at different orientations. If the bearing preload changes as the headset is rotated, the headtube should be faced. Thanks for this thorough explanation!

grognaak
08-28-2019, 01:33 PM
Thank you! What are the consequences of prolonged riding with a too loose or too tight headset?

palincss
08-28-2019, 01:40 PM
A damaged headset.

paredown
08-28-2019, 02:40 PM
When they were steel, the chances of damage was less. I have resorted to taping the wrench faces now that everything is alu.

The other 'trick' is to tighten the bottom nut down a little tight, then the hand tighten the top nut down to that. Then hold the top nut steady, and back the bottom nut up tight to the top one. It seems easier to hold the clearance constant, since when you cinch down on the top nut, it does tend to compress both nuts down, and alter the clearance that you have tried to leave.

A second comment--sometimes if it feels as if there is no half-way between too tight and too loose (at which point i usually take the whole thing apart to ensure that I have not had a brain freeze and installed something incorrectly)--and particularly if it seems the point at which it binds is different side to side--is to check carefully that the cups are seated squarely in the head tube, and down tight to the frame. If the whole gizmo is not squarely compressing as you tighten, the binding will show up as a slight difference.

Third comment--if the headset is well-used and been left too loose, you also might get uneven feeling because of ball-bearing wear (also true just from wear(; if it had been left too tight you could get brinelling--a series of ball bearing shaped divots in the races that makes if feel 'clicky' when tight, so check balls and races carefully while assembling.

icepick_trotsky
08-28-2019, 02:56 PM
Riding with a poorly adjusted headset can also risk damaging the threads on your steertube, which can wreck the fork. I've done this before.

jemdet
08-28-2019, 03:14 PM
Don't worry about the locknut until you have the preload correct. Like others have said - make sure there's no play but that the wheel can turn freely. Keyed washer b/w the locknut and adjustable nut.

Use one wrench to keep the adjustable nut from turning while you tighten the locknut with a second wrench. Only the locknut should be turning. Make it really tight. Tight tight. You're pushing three flat pieces of metal against one another. I'm not sure that John Henry could overdo it.

donevwil
08-28-2019, 03:17 PM
Once I picked up one of these marring the locknut became history.

http://www.missinglinkschool.com/images/product/spr_HW-2.png

Mark McM
08-28-2019, 03:29 PM
Don't worry about the locknut until you have the preload correct. Like others have said - make sure there's no play but that the wheel can turn freely. Keyed washer b/w the locknut and adjustable nut.

Adjusting the headset pre-load on a threaded headset is often an iterative process. Due to clearances in the threads (which are required, or else you wouldn't be able to screw threaded parts together), the pre-load with the locknut loose will be different (looser) than with the locknut tightened. This is one of several reasons that threadless steerers/headsets are better.

weisan
08-28-2019, 03:53 PM
chicks dig guys with scars...

https://static.onecms.io/wp-content/uploads/sites/35/2017/08/04011035/skyword-image-468197.jpg

Hindmost
08-28-2019, 04:42 PM
Aluminum cups and lock ring? Yeah it's a problem.

Just know during initial adjustment there's going to be several trial and errors so don't take things to full tightness, just very light tightness at first. Try not to use much force on the cup, just hold the position of the cup with a wrench and only move it after releasing the force from the lock ring. And only put full force on to the lock ring when finalizing adjustment. The slotted washer should prevent rotation of the cup for the most part. (Make sure the slotted washer can move freely up and down the steer tube. Carefully file the inner surfaces of the washer or clean up the steer tube if it doesn't.) Full force just has to be pretty firm, not wicked firm. The size of the wrenches give the impression that you use mega-torque. If there's space try putting masking tape on the faces of the wrench flats.

Oxford_Guy
08-29-2019, 12:16 PM
Once I picked up one of these marring the locknut became history.

http://www.missinglinkschool.com/images/product/spr_HW-2.png

This tool doesn't seem to be available anymore, is there anything currently available that is as good (espc. on an aluminium headset)?

speedevil
08-29-2019, 12:46 PM
The simplest way to check the headset preload on a threaded steerer is to apply the front brake and move the bike forward and backward. When there is no movement of the fork, the preload is set correctly.

This presumes that you're tightening the cone and removing play, because if it's already too tight you won't have any fork movement either.

I use cellophane tape on the top nut to prevent marking it when tightening it down. If you hold the cone with the headset wrench and snug the top nut down, the preload shouldn't change much if at all. This presumes that you have the keyed washer on top of the cone.

Riding with the headset loose will cause "brinelling" (I think that's the correct term) and the bearing balls being much harder than the alloy cup races will make tiny indentations in the races. As a result the bar movement can feel "notchy". If the bearing balls are in a retainer, sometimes you can extend the headset life by using loose balls without the retainer.

ultraman6970
08-29-2019, 04:56 PM
I been looking for that headset wrench for the longest time.

What surprise me is that everything that is in the market, eventhought should be at least close to specs, they arent... always lose... use them 10 times and they get worse...

It is what it is tho...

donevwil
08-29-2019, 05:37 PM
This tool doesn't seem to be available anymore, is there anything currently available that is as good (espc. on an aluminium headset)?

Wow, I had no idea. Must no longer be profitable tool in this threadless age. Last time in my LBS (~6 mo ago) they had one hanging on the tools for sale pegboard. Unfortunately they're now out of business.

Oxford_Guy
08-30-2019, 05:41 AM
I been looking for that headset wrench for the longest time.

What surprise me is that everything that is in the market, eventhought should be at least close to specs, they arent... always lose... use them 10 times and they get worse...


Has anyone tried this one, if so, is it any good?:

https://www.steintool.com/portfolio-items/headset-locknut-wrench/

Tony T
08-30-2019, 06:28 AM
This tool doesn't seem to be available anymore, is there anything currently available that is as good (espc. on an aluminium headset)?

Might find something close with a search for a flare nut wrench

ultraman6970
08-30-2019, 07:43 AM
No idea about that one... for 35 bucks isnt that much for a quality tool. The issue tho is that doesnt look you can use it for the bottom nut tho.

Has anyone tried this one, if so, is it any good?:

https://www.steintool.com/portfolio-items/headset-locknut-wrench/

Skenry
08-30-2019, 09:34 AM
For saving and protecting your headset parts, I always go for the smooth joint pliers. Knipex makes the best but these are great for home use.
https://www.amazon.com/Tools-VISE-GRIP-GrooveLock-10-inch-4935097/dp/B0030XMFW0

But seriously, who else is feeling really old reading this.....?

ultraman6970
08-30-2019, 09:47 AM
Smooth jaw? did not know they had that... looks like a great solution IMO.

Tight to the T solution w/o scratching anything. I imagine they work really well in pedals aswell?

fmradio516
08-30-2019, 10:29 AM
the knipex "plier wrench" is my recently discovered favorite tool.

Brian Smith
08-31-2019, 11:44 AM
Has anyone tried this one, if so, is it any good?:

https://www.steintool.com/portfolio-items/headset-locknut-wrench/

Yes, the Stein tool is good, in keeping with most of their products.
Really though, for users on this forum with a question about a headset locknut tool...a quality adjustable wrench such as those from Crescent, in a 12", 15", or 18" size, will not only do the just as well or better, but will have other useful applications.
The headset locknut tools can only be as good as these at the task of turning the locknut without marring, not better, and they can add a little speed in a professional setting. Are you assembling 8 bikes out of boxes with the same 8-point 32mm locknut dimension? Sure, in that case these might be worth buying. Are you instead adjusting 1 headset with such a locknut and want to really cinch it down for a "lifetime" adjustment? A 15" Crescent allows you to more easily reach the goal without marring, and adjusted properly it won't mar even your thinnest 5-thread aluminium locknuts, and is compatible with 32mm and 36mm locknuts as well as walloping the backside of an L-bend 6mm hex key wrench to free the stem cone possibly done in the same setting.

pbarry
08-31-2019, 12:31 PM
Yes, the Stein tool is good, in keeping with most of their products.
Really though, for users on this forum with a question about a headset locknut tool...a quality adjustable wrench such as those from Crescent, in a 12", 15", or 18" size, will not only do the just as well or better, but will have other useful applications.
The headset locknut tools can only be as good as these at the task of turning the locknut without marring, not better, and they can add a little speed in a professional setting. Are you assembling 8 bikes out of boxes with the same 8-point 32mm locknut dimension? Sure, in that case these might be worth buying. Are you instead adjusting 1 headset with such a locknut and want to really cinch it down for a "lifetime" adjustment? A 15" Crescent allows you to more easily reach the goal without marring, and adjusted properly it won't mar even your thinnest 5-thread aluminium locknuts, and is compatible with 32mm and 36mm locknuts as well as walloping the backside of an L-bend 6mm hex key wrench to free the stem cone possibly done in the same setting.

+1, Big Crescent works great.

JMO, but I rarely use a “lock washer” as it makes adjustment harder, and steel examples can cut into the threads. Plain washer or file off the tongue. A wheel installed on the fork will prevent the fork from rotating when tightening the headset. Did not read every post so forgive me if the above was already said. :)

54ny77
08-31-2019, 02:09 PM
I always use a very thin t-shirt as a buffer between metal on metal, i.e. cone and crescent wrenches on headset lock rings. Works great, no scratches.

Ralph
08-31-2019, 02:43 PM
I always used two Campy wrenches. Very tight fit. Not much play between wrench and nut. Would tighten the bottom one slightly against the top one....because headset bearing would tend to over tighten as you snugged it up.