Headset repair - and wheel rims

[lewis noble]

Hello!

I would welcome some advice regarding my Sherpa headset.  I was re-fitting a bell (steerer tube mounted, in the spacer stack) and the star nut near the top of the tube seems to have failed - it needs very little tension to make it slip right up to the top as you pre-load the bearings.

I've done this job many times, and I know the preload has to be 'just enough' and carefully set - but it makes it impossible to get an accurate setting.  I've got the bike rideable and secure by seating everything carefully and tightening up the stem, so I can get it to my LBS if need be,  but I need to sort it out properly.

Is a special tool needed? Or just drift the nut into the tube with any close-fitting piece of dowel or socket set extender and re-assemble??

I'll have a look at Sheldon Brown, but any advice on here would be welcome.

And another thing . . . . Wheel rims!!  brakes (XT with KoolStop Dual Compund have started squealing much more - especially now the headset is not set properly! I'll be fitting new pads, which have had plenty of use, but any advice re cleaning wheel rims?

Thanks guys.

Lewis

[geocycle]

Sorry to hear of the star nut.  If it were me I would push the old one down the tube out of harm's way then insert a new one.  I found a broom handle works well but I'm sure there is a more elegant solution. I'm afraid I don't clean wheel rims!

[lewis noble]

Thanks Geo - hope you are keeping OK.

Broom handle sounds fine to me!!  In fact, the old nut is so easy to withdraw I can get it out with my fingers . . . . .

Best wishes

Lewis

[leftpoole]

Lewis,
Pop down to Slimbridge and have a cuppa.
I suggest that you bring your forks. I have the proper tool for the job which you can use.
All other methods are improvising.
Of course you could do as I have always done-buy one yourself!
Regards,
John

[alfie1952]

Lewis,,
If you can remove it, why not remove it an use a headset doctor which is an expanding plug which is tightened with the headset bolt. A little more expensive than a starnut but does the job.

Alfie.

[lewis noble]

Thanks guys, plenty to go on already!

I saw you were back in Gloucestershire, John, best wishes. No immediate plans for a visit down there, but who knows . . .

Checking what spares etc available at LBS.

Lewis

[leftpoole]

Lewis,
The suitable tool can be found cheaply on Ebay.
John

[bobs]

Lewis,

I always fit one of  these.

https://www.sjscycles.co.uk/headsets/problem-solvers-locking-headset-spacer-for-1-18-inch-black/

I find it makes life much easier when doing anything to do with the stem and handlebars.

Bob

[mickeg]

Sorry to hear of the star nut.  If it were me I would push the old one down the tube out of harm's way then insert a new one.  I found a broom handle works well but I'm sure there is a more elegant solution. I'm afraid I don't clean wheel rims!

No.

I did this on a foldup bike, worked fine.  But since the Sherpa has a piece of steel welded across the bottom to attach a fender, you would not be able to drive the old star nut completely out the bottom.

So, if you can extract it out the top, that is what you should do. 

Star nuts are quite inexpensive.

I have never taken one out the top, but I think that some have done so after they drilled out part of the old star nut.  A google search may help?

Lewis,,
If you can remove it, why not remove it an use a headset doctor which is an expanding plug which is tightened with the headset bolt. A little more expensive than a starnut but does the job.

Alfie.

I used one of those expanding type ones on my last build as a temporary measure.  My plan was to use that while I decided where to cut the steerer after I rode the bike some and then put in a star nut later.  I actually did not cut the steerer tube, I have since installed a star nut.

I did however have problems with the expander thingy, I applied frame saver to the bike before assembly, that included the inside of the steerer tube.  The expander did not grip tightly until I cleaned out the framesaver with solvent.  But otherwise the expander worked fine.

[Danneaux]

Agreed with mickeg; driving the SFN down or through is not so great on a bike with a semi-closed steerer, as on the Thorn.

In your case, Lewis, removing the SFN seems to be an easy task. For those whose SFN is not so loose, it is almost as easy to drill it out.

I have never taken one out the top, but I think that some have done so after they drilled out part of the old star nut.  A google search may help?

I wrote up a little tutorial on how to do so some time ago:

http://thorncyclesforum.co.uk/index.php?topic=3800.msg16380#msg16380 Thumbnails were broken during the last Forum software upgrade, but if you click on the generic icon, the photos will appear.

I have since fitted a removable tension nut to my two bikes with threadless steerers. They're a lot simpler and often available inexpensively. I purchased a very nice one from eBay for only USD$1.25, shipping included.

All the best,

Dan.

EDIT to correct an error in the link. -- Dan.

[lewis noble]

Thanks Dan and everyone . . . . Sorted it out I think.  New SFN was even looser than the original, dropped right down to bottom of the steerer tube! And yes, Sherpa forks, including the 853 ones, are not easy to access from below.  But I got it out by inverting bike, removing mudguard, poking out with electric cable.

I re-used the old SFN - if it has worked before, the chances are it will work again.  'Spread' the wings a bit with pliers, refitted, and all well. Took the opportunity of renewing pads, which were probably past their best, cleaning wheel / rim (Muck-Off, rinsing, wiping clean, and all fine and squeal free.

Asssuming all continues OK, no need to consider alternatives, but thanks for suggestions.  I presume the fixable spacer fits under the stem, and locks things, but does not help with fine adjustment of pre-load? Cap bolt still needed for that? In my experience, getting pre-load right is very important.

And the expander thing, would that work if spacers fitted above stem? I have two small spacers in this position.  But for the time being, this is not needed I reckon.

Thanks Dan for link to 'removal' thread.

Lewis

Biggest hassle was fitting the pins into the new brake blocks to secure them in the holders - always awkward and must get eyes tested . . .

Lewis

[Danneaux]

And the expander thing, would that work if spacers fitted above stem?

Yes. The removable tension nut or plug fits inside the steerer, with only a slim collar no larger than the steerer's outside diameter to keep it from slipping down. As far as headseat spacers are concerned, it is transparent. The collar on one of my plugs is about 2mm thick, the other about 2.5mm. Neither affects the use of spacers or handlebar/stem height.

Below, I've attached several photos of a spare expander plug. Word descriptions are okay, but it helps to see an example. Basically, it slips into the steerer, then you tighten the bolt whose cone-shaped end causes the "wings" expand, locking the plug into the steerer. There are threads in the center of the plug's expansion bolt. These serve as the nut to capture the end of the steerer cap tension bolt. Just as you would with a quill stem, it is a Very Good Idea to grease the removable steerer plug before installation. This prevents galvanic corrosion between the steel steerer and the aluminum plug "wings". Mine is clear anodized, but still a good idea to use lube to prevent future seizing.

So glad to hear of your success! Yay. 

All the best,

Dan.

[mickeg]

Good description Dan.

I did not intend to use it permanently, months later I replaced it with a star nut after I decided not to cut my steerer tube on that bike.

The problem I had with one of those was that I used frame saver inside my steerer tube.  That hardened up to a very soft solid that coated the inside of the tube.  That soft solid turned into a lubricant on the expander part and it also clogged up the expander teeth so that it could not develop a good grip on the steerer tube. 

[Danneaux]

<nods> Yes, I can sure see how that would be a problem, mickeg.

All the best,

Dan.