Headset Detent

[gregoryoftours]

Does it look like this?

Screenshot 2021-03-09 at 17.45.54.png
Jonathan

Yes, exactly like that! And that quill stem design leaves a lot to be desired, the way the clamp works. I swapped the bars soon after I got the bike and had to use a slim pry bar to open it up enough to get the old bars out and the new ones in.

It's not unusual to have to pry a quill stem apart to aid fitting, try fitting a set of drop bars to one. Nitto, a stem and bar manufacturer, sell a tool for the purpose https://southerndistributors.co.uk/prod ... stem-tool/

Some quill stems have a little grub screw that is used to spread the clamp a bit for installation. This one is a 3ttt record-

[Brucey]

I'm with Jobst Brandt on this subject.

https://yarchive.net/bike/head_bearing.html

all very interesting I'm sure but I do wish folk would stop wheeling this out as if it were gospel; it isn't. Sadly JB was wrong on several counts eg

1) you could have true brinelling and you would see the dents and not the raised material around the sides, because one would be a tiny fraction of the vertical dimension of the other so this 'observation' (that he didn't see raised material only indents) certainly doesn't "prove" fretting. Indented headsets can occur in just a few miles; again not consistent with fretting.
2) Brandt's steerer was absurdly long (over 10" between races IIRC), only 1" diameter and the frame was built light, so the steerer trim wouldn't have favoured stiffness, shall we say. There would have been significant deflections in the steerer which were not considered. In my own bikes I have one frame with a head tube about 3/4" longer than the others and the steerer is noticeably more flexible.
3)When the steerer flexes the load isn't shared between balls in a headset with standard raceways, so the whole load can indeed be seen by three or four balls only. Hence indenting via gross yield (brinelling).

All of which means that what other people were trying to tell Brandt was correct; his headset had an anomalous setup and his experiences were likewise anomalous. Red herrings such as hammering head races together and claiming that this is representative of service loads somehow just don't help either.

JB changed to a 1-1/8" steerer (less likely to flex) and a cartridge bearing headset (which better accommodates flexing). However the experience of anyone who uses frames with medium length head tubes and controls the preload on good quality (and well installed) 1" headset bearings correctly has always been that the headset is likely to outlast the rest of the bike.

FWIW I have seen numerous cartridge bearings which failed, and sometimes they damaged the seatings and took them out as well. IMHO if the bearings are not to move around too much there needs to be quite a lot of preload and the service loads are closer to the maximum load the bearings can sustain (because all things being equal, there are fewer, smaller balls in a cartridge bearing headset than in a traditional one. And whilst cartridge bearings can articulate on their seatings it isn't a very good arrangement if they are forced to do so on a continuous basis.

FWIW if you have a cartridge bearing with 36x45 writ upon it, it means one shoulder angle is 36degrees and the other is 45 degrees.

cheers

[OldLimey]

That sounds like what I did. I snugged the adjusting race down and then tightened the locknut. That made the steering very slightly stiff. So I slackened the adjusting race just a hair without loosening the lock ring.....

not quite. If you don't back the lockring off, whatever load you apply to the locknut ends up being the preload on the bearings. Anything which involved a spanner is probably too much. Using "Luke's trick" only definitely doesn't overly preload the bearings if you tighten the locknut and adjusting race hand tight, i.e. without using a spanner at that point.

cheers

The adjusting race and locknut both turned together so that it wasn't too tight on the bearing.

[francovendee]

I changed the headset on my A-head headset last year. It was the first one I'd attempted and it all went surprisingly well.
After a few weeks of use I notice there was play in the headset. I thought this strange but as everything looked right made and adjustment. After another few weeks It again had play. I didn't like the idea but adjusted it once again. I was worried I'd over-tightened in removing the play but nothing seemed to going wrong. Headset is easy to turn and no play.
Brucey mentions settling so I'm hoping that's all it was.

[rogerzilla]

They shouldn't settle if they're pressed in firmly (and there isn't thick paint on the seating faces). I have known a slight settling on repainted frames, where the refinishers may ream out the head tube but not re-face the top and bottom to remove paint from there - it does prevent cosmetic rust, I suppose. The paint isn't as hard as metal so you can get some creep.

[Brucey]

with an A-head headset a major source of settling can be in the wedge part (where fitted). It is not unusual for this to settle and require several adjustments.

cheers

[531colin]

with an A-head headset a major source of settling can be in the wedge part (where fitted). It is not unusual for this to settle and require several adjustments.

cheers

They settle on titanium bikes..... no paint!

[francovendee]

They shouldn't settle if they're pressed in firmly (and there isn't thick paint on the seating faces). I have known a slight settling on repainted frames, where the refinishers may ream out the head tube but not re-face the top and bottom to remove paint from there - it does prevent cosmetic rust, I suppose. The paint isn't as hard as metal so you can get some creep.

Maybe that was it, they hadn't been pushed in hard enough. It was my first time of doing it so didn't want to overdo do it. Since the second adjustment it's been fine.

[Brucey]

with an A-head headset a major source of settling can be in the wedge part (where fitted). It is not unusual for this to settle and require several adjustments.

cheers

They settle on titanium bikes..... no paint!

IME the wedge settles on the steerer to some extent, regardless of the materials involved (in both wedge and steerer). I have seen quite a few carbon steerers badly worn where the wedge didn't stop moving around in service....

cheers

[MikeDee]

I'm with Jobst Brandt on this subject.

https://yarchive.net/bike/head_bearing.html

I have never had any such issues with cartridge bearing headsets, where there are plain bearing surfaces to take the rocking motion. Some of mine (Cane Creek S2 and S6) have a decade and 10,000 miles on them with zero attention. They are still perfect.

I found the old loose ball headsets on road bikes could go notchy within 500 miles. Shimano 1055 was really bad for this.

Me too. I've got an original 1" threaded Deore LX cartridge bearing headset on a 20+ year old bike and it still turns smoothly/is not notched. The only headsets I've had get notchy are the looseball types. Never had a failure of a cartridge bearing headset except on a Cannondale mountain bike where sweat got into the bearing.

Another advantage is if cartridge bearings fail, they can be easily replaced, vs. the looseball/caged bearing types that need new headset cups pressed out and into the head tube; crown race also.

The cartridge bearing headset is a superior design in many ways.

[willcee]

Dunno why you think that, In my lifetime I have replaced several hundred ahead types and they can and often do suffer detent notchiness.. yet a 1932 Raleigh that I sold last year, having totally restored it and owned since the early noughties only required new balls, the cups and the screw down rings were like new inside even though the exterior nickle plating took some attention .. the problem is water ingress ,rust , a lack of good grease, cheaper materials being used, and initial fitment being left to those whom I wouldn't ask to blow up a football..the price thats asked for a decent quality headset today is quite ridiculous... the best thing about ahead is usually the ease of replacement , that is if you can trawl your way through the thousand and more patents...just my experience.. will

[MikeDee]

Dunno why you think that, In my lifetime I have replaced several hundred ahead types and they can and often do suffer detent notchiness.. yet a 1932 Raleigh that I sold last year, having totally restored it and owned since the early noughties only required new balls, the cups and the screw down rings were like new inside even though the exterior nickle plating took some attention .. the problem is water ingress ,rust , a lack of good grease, cheaper materials being used, and initial fitment being left to those whom I wouldn't ask to blow up a football..the price thats asked for a decent quality headset today is quite ridiculous... the best thing about ahead is usually the ease of replacement , that is if you can trawl your way through the thousand and more patents...just my experience.. will

If you get water in the headset bearing, it's going to fail regardless of whether you have a cartridge or looseball headset. Also, experience with cheap, inferior headsets is irrelevant to this discussion as well, as one would expect them to fail early.

[willcee]

HEY.I never mentioned anything cheap .I mentioned cheap materials,thats irregardless of the asked for price and if you knew how easily water gets into a aheadset you may then be in position to offer critique.. generally praising sealed bearing cartridges when they lie down and fail on a road bike more often than you realise,esp the lower race ..certainly more often than those in an old school screw down cup type..no diss intended, just clarity and experience..will

[MikeDee]

but using Luke's trick, you hold the locknut steady (and the forks/handlebars too, eg. with the front wheel between your legs), then back the adjusting race into the locknut by turning the adjusting race ACW. This allows the headset adjuster to be set tight against the locknut, but without rotating the locknut. With a following wind, the preserves whatever preload was applied to the bearings when the locknut was hand-tightened. In just a few seconds it often gives an adjustment which is as good or better than you might achieve in a few minutes otherwise; clever stuff!

cheers

I would think you should do the opposite and hold the adjusting cup with one wrench to keep it from turning, and tighten the nut with the other; otherwise you are decreasing the preload on the bearing.

Also, I thought the purpose of the keyed washer is to keep the adjusting cap from turning when you tighten the locknut? I don't see how having the keyed washer in there or not matters much to this tightening method.

I've also had the preload change after I install and tighten the stem, as I remember, but it's been a long time since I've messed with a threaded headset.

What does "With a following wind" mean?

[rogerzilla]

Funny things happen when you tighten the locknut. It is correct that you should tighten the adjustable race and the locknut against each other - this goes for all the bearings on the bike - but sometimes, even if you hold the adjustable race rock-steady relative to the fork, the adjustment changes one way or the other because of elaaticity in the arrangement. Personally, I always throw the locktab washer away because it never does its job.

A loose headset chatters if you pick up the front end of the bike and drop it from a few inches. A tight one is harder to diagnose, but if the fork turns using only one finger and thumb on the headset spanner flats, without a wheel in place, it's good.