jb wrote: ↑6 Oct 2021, 3:35pm
I think your steerer tube is too long, try a thin spacer under the stem casting as suggested upthread. This will allow the top screw to pull the hole thing together and load the bearings thus removing the play.
After you have replaced the broken star washer and nut of course.
Thanks for everyone’s help, and I will get a thin spacer while I’m at it.
There will probably be more question anon
The star nut has broken. Effectively the nut part has broken away from the star part. The nut is still screwed onto the bolt. The existing broken star needs to be hammered further down the steerer tube and the nut removed from the bolt in the top cap. You will then be able to install a new star nut. Have a look on the Park Tool site re how to do this as you need to keep it straight and only hammer it down to the right depth. It's easy with the right setting tool but can be done without it.
If the star nut has been mangled it suggests you have applied too much force. The method for adjusting the assembly is totally different to the conventional, traditional quill stem, part of which is held inside the steerer tube and requires tightening to a much greater degree.
I suggest you look at an online tutorial video or entrust the rectification to your LBS.
The older I get the more I’m inclined to act my shoe size, not my age.
I should probably also write something about how the star nut came to get broken - the top cap bolt exists only to set pre load so you should never have to crank it up hard. The previous comments about loosening the stem bolts, checking for missing parts etc all apply. There may also be something seized onto the steerer - eg the the stem and/or spacers below the stem - so that as you tightened the top cap bolt it didn't have any effect on the bearings. It needs disassembling to understand what is wrong, and a good read up of how aheads work.
HTH
Edit: cross post with peetee (just in case you thought we were ganging up on you!)
TheBomber wrote: ↑6 Oct 2021, 4:14pm
I should probably also write something about how the star nut came to get broken - the top cap bolt exists only to set pre load so you should never have to crank it up hard. The previous comments about loosening the stem bolts, checking for missing parts etc all apply. There may also be something seized onto the steerer - eg the the stem and/or spacers below the stem - so that as you tightened the top cap bolt it didn't have any effect on the bearings. It needs disassembling to understand what is wrong, and a good read up of how aheads work.
HTH
Edit: cross post with peetee (just in case you thought we were ganging up on you!)
What I meant to also write was to ask how old this bike is? If the headset is indeed loose and has been for a while I would question if the thing was correctly adjusted from new with an adequate number of spacers.
In my experience loose headsets are not uncommon. Quite often this is down to user error when handlebar height is changed, for example, but often they are not properly set up when sold or the problem is just overlooked when the bike is serviced. On cheaper mountain bikes, for example, suspension forks can have quite alarming for/aft play and the resultant clunking feels identical (through the handlebars, at least) to a loose headset. I think quite often less experienced or less thorough mechanics who deal with a lot of budget bikes will be so used to that characteristic that they have learned to ignore it or just assume the fault lies in the forks - assuming they notice it at all!
The older I get the more I’m inclined to act my shoe size, not my age.
The bike is fairly old, 9 speed with shimano 105 parts and flight deck shifters, so probably ten plus years old.
It has been well looked after by the looks of it, just the headset issue and worn brake blocks from what I have discovered.
The guy I bought it off said he bought it from a friend and my guess would be that it may have been like this in his ownership.
Star fangled nuts are relatively cheap, and it is a doddle to fit one with a setting tool, like the Lifeline one in the link below. If you don't have a setting tool and cannot borrow one, it is possible to make one using a socket as shown in the video below. I would advise against trying to install the star nut without such a guide tool, because it is difficult to keep the nut aligned.
However, if the headset is wrecked, then it may be best to let a bike shop fit the star nut at the same time as installing a new headset.
slowster wrote: ↑6 Oct 2021, 5:18pm
Star fangled nuts are relatively cheap, and it is a doddle to fit one with a setting tool, like the Lifeline one in the link below. If you don't have a setting tool and cannot borrow one, it is possible to make one using a socket as shown in the video below. I would advise against trying to install the star nut without such a guide tool, because it is difficult to keep the nut aligned.
However, if the headset is wrecked, then it may be best to let a bike shop fit the star nut at the same time as installing a new headset.
I have already bought that very tool. I don’t really like buying a tool that I probably won’t need to use again but it’s almost certainly cheaper that getting a bike shop to do it.
I like to do jobs on my bikes myself if I can, and there are several people here willing to help (thank you) if I get stuck.
Most of the bikes I have owned are from the classic era, for me mid 70’s to mid 80’s and I am at home there but have to stop and think with bike parts after then if it’s technical. Hi
The star nut demonstrates what a poor design aheadsets are. Basically it's a nut held in place by a piece of springy metal knocked into a tube. If any part of it breaks it has to be knocked through the tube.
I've used FSA compression adjuster They are meant for carbon steerers where the usual crude star nut cannot be used, but they work on metal steerers. The allen key hole I fill with soft wax to prevent water ingress.
"It takes a genius to spot the obvious" - my old physics master.
I don't peddle bikes.
Good morning gentlemen.
Was planning a ride this morning but as its miserable and wet I decided to crack on with the headset problem.
I managed to get the remains of the S/F nut out and removed the fork and this is what I found.
My guess is the someone changed the forks at some point and fitted the old headset back and it has always been loose.
What I can't understand is the difference in size, surely the forks are not under sized or the crown race oversized.
What I really don't know is what to do about it.
A.) to fit a new Euro/ISO headset, or at least the bottom part of one, or
B.) to find and fit a crown race from a Euro/ISO headset that would be compatible with the lower cup of your existing headset. My guess is that might be very difficult/impossible.
As slowster says. It looks as if the original forks and frame were made to the Jis standard and the replacement forks were iso sized. If you search on this forum I recall people fitting Jis crown races to iso forks using a shim or packing. I will have a search.
Here you go this is the one I remembered, bit of cardboard and araldite. A real bodge, but quite successful.
Option A from slowster's reply might mean you need to get the head tube enlarged to the ISO 30.2mm standard. This was a common frame modification back when 1" headsets were popular. Are the cups loose in the frame (suggesting that the frame is already set up for an ISO headset)?
It looks on closer inspection that someone has filed down the bottom of the fork where the crown race sits.
I have made a coke can shim on fitted it inside the crown race, it seems less sloppy but won’t know for sure until the star tangled thing arrives.
If it works would you guys consider it a permanent fix, it is a bit Harry Tate isn’t it.
