Self loosening headset

[presta]

Sadly I have only one lock nut

You have one locknut (the hexagonal one), and one bearing cup (the knurled one), you need to tighten the former against the latter. To do this, you tighten the bearing cup just far enough to eliminate the free play without the bearing nipping, then hold it still whilst you tighten the locknut against it. Since the bearing cup has no flats, you'll need something like a pipe wrench or mole grips, because you won't be able to hold it still enough with your fingers.

 

[raleighnut]

Sadly I have only one lock nut, it goes knurled nut, two interlocking parts ( that don't seem to do anything) the washer/cable hanger then one lock nut that is round at its base, hopefully the photo is clear.

Ah it has the serated washer, you need to really undo the top nut, lift the serated washer and undo the knurled nut a fraction then tighten down the top locking nut.
What I strongly suspect has happened is that the knurled nut has been forced tighter which will cause the serated washer to turn and force the tang that sits in a groove on the steerer to jump out in which case you really need to take the whole lot apart EXCEPT the knurled nut and then replace the serated washer in its correct location (this prevents the lower knurled nut from turning) and then reassemble.
One point though the headset needs to be slightly loose before fitting the serated washer as tightening the top locknut forces the serated nut to compress onto the lower knurled nut slightly tightening the nut onto the bearings. A lot of people don't know about the serated washer and force the lower knurled nut tighter with a pair of grips negating the effect of the serated washer and leading to the problems you are having.

This setup is unique to Raleigh bikes and getting the right amount of 'slackness' is a bit of a pain and can take several attempts to get just right.

 

[raleighnut]

You have one locknut (the hexagonal one), and one bearing cup (the knurled one), you need to tighten the former against the latter. To do this, you tighten the bearing cup just far enough to eliminate the free play without the bearing nipping, then hold it still whilst you tighten the locknut against it. Since the bearing cup has no flats, you'll need something like a pipe wrench or mole grips, because you won't be able to hold it still enough with your fingers.

No that's how you wreck that particular Raleigh set up, the knurled nut won't turn without removing the serated washer above it that is locked to the steerer. it can be forced to turn but that twists the tang out of the locating groove in the steerer tube and stops the whole Raleigh design from functioning,

Yep it is a silly design but it does work unless you butcher it.

 

[midlife]

Doe you have these bits, knurled top race and the serrated washer ?

 

[raleighnut]

Doe you have these bits, knurled top race and the serrated washer ?

View attachment 633243

Ooh a Stronglight one, nice photo I thought the were a Raleigh only design but yep going by the photo that's what the OP has.

The serated washer has a tang that locates in the fork and prevents the bottom (knurled) nut from rotating unless some heavy handed butcher grabs it with a pipe wrench and forces it to

 

[rogerzilla]

The locktab washers don't usually work unless you have a plain spacer or two above them. This helps stop the locktab being dragged round by the top nut.

 

[Illaveago]

Great idea ! Hours of fun trying to set it up. Then you find that the lamp bracket it out of align and you can start all over again !

 

[midlife]

The locktab washers don't usually work unless you have a plain spacer or two above them. This helps stop the locktab being dragged round by the top nut.

I think the OP has a hanger for the front centre pull which should help

 

[rogerzilla]

I think the OP has a hanger for the front centre pull which should help

Ah yes...hold onto the hanger while tightening the locknut, if the adjustable race is only knurled.

 

[gbb]

While hoping Shacks got it sorted, a classic although rare reason for nuts coming loose is stripped or damaged threads.
I once had a cheap hub that i could adjust up perfectly, only for it to go out of adjustment a few days later. After a couple occurences of this, a close inspection revealed damaged threads on the axle (equally the threads in the nuts can get damaged too)
Always worth checking.

 

[Shack]

Ah it has the serated washer, you need to really undo the top nut, lift the serated washer and undo the knurled nut a fraction then tighten down the top locking nut.
What I strongly suspect has happened is that the knurled nut has been forced tighter which will cause the serated washer to turn and force the tang that sits in a groove on the steerer to jump out in which case you really need to take the whole lot apart EXCEPT the knurled nut and then replace the serated washer in its correct location (this prevents the lower knurled nut from turning) and then reassemble.
One point though the headset needs to be slightly loose before fitting the serated washer as tightening the top locknut forces the serated nut to compress onto the lower knurled nut slightly tightening the nut onto the bearings. A lot of people don't know about the serated washer and force the lower knurled nut tighter with a pair of grips negating the effect of the serated washer and leading to the problems you are having.

This setup is unique to Raleigh bikes and getting the right amount of 'slackness' is a bit of a pain and can take several attempts to get just right.

Thanks for the detailed explanation, Sort from my old Raleigh I haven't seen a serrated washer before or since. I've done what you say and fingers crossed, work is a sadly getting in the way now for a decent test ride.

 

[Dogtrousers]

I remember washers with a "tang" in them to stop the locknut from rotating the top race, but my memory is of a flat, not serrated washer.

I also have a memory of steerer tubes that were threaded, but had two flats on either side, so the thread didn't run all the way round, and a washer with matching flats that also wouldn't turn. Maybe I dreamt that one after a particularly lavish toasted cheese supper.

 

[Shack]

Well thanks again everyone, an afternoon on some of Cornwall's finest bumpy and steep descents still sees me good and tight.

 

[Illaveago]

Well thanks again everyone, an afternoon on some of Cornwall's finest bumpy and steep descents still sees me good and tight. View attachment 633835

Is that a Granada ?

 

[Shack]

Get it is, although it's only the frame/forks and rack that are still original, everything else has worn out or been replaced over the years. Still my go-to bike, although various and more modern others keep it company in the garage.