Pushbike headset adjustment

[Asha]

Having cycled all my life ( road bikes), I'm familiar with the mechanics and can pretty much dismantle and rebuild a bike however this evening I have come across a headset that I am not familiar with.

This one:

https://www.amazon.co.uk/XLC-ST-L02-A-Head-Vorbauerhöhung/dp/B07HT6PS9W

It is a friends hybrid GIANT bike, the headset of which has started "knocking" slightly and needs to be nipped up. ( Unlikely to need replacing atm imo but that is to be seen)

I expected to attack it with an allen key, spend five mins and have it all adjusted and running smoothly but upon removing the rubber bung in the top of the stem, I was surprised to find no sign of an "allen key bolt" to slacken / tighten to make necessary adjustment.


Slackening the allen key bolts on the clamps loosened nothing although I am aware that it is possible the whole stem is perhaps blocked as it is a number of years old.
The only movement evident was the rise and fall of the handlebars ( on their stem) when the QR lever was released.

So my question is, How is this headset / stem system attached to the forks and how is adjustment made to the bearings / cups that are situated below it?

 

[Comfortably Numb]

Have you had a look with a torch, in case the bolt is at the bottom of the tube? It would obviously have to below the extending part

 

[Asha]

Have you had a look with a torch, in case the bolt is at the bottom of the tube? It would obviously have to below the extending part

Yes I looked ( admittedly not with a torch) and immediatly thought that the hole I could see in the center of what looks to be a silver bolt would be allen key fit but tbh it appears to be nothing but a circular hole ( about 4mm diameter)
It's going to require a long allen key or whatever wrench, to reach it I think.

 

[hunnymonster]

Try googling "star fangled nut" - does that look like what you see?

 

[Asha]

Try googling "star fangled nut" - does that look like what you see?

Now then that might be it…...

I don't have the bike here, he called on his way home from work then left with the bike.

I''d have to take a closer look with a torch like Daron suggested to confirm but if it is that type of fitting then I can't help as I don't have a suitable tool.

 

[hunnymonster]

There are heaps of vids on YT on adjusting it - essentially the top cap pushing down on the stem clamp is the adjustment.

It's something like "Ahead headset"

Removing the star fangled nut is not something you should ever need to do

Here's one

View: https://youtu.be/ZK5u5ioZU8M

 

[Asha]

There are heaps of vids on YT on adjusting it - essentially the top cap pushing down on the stem clamp is the adjustment.

It's something like "Ahead headset"

Removing the star fangled nut is not something you should ever need to do

OK I'll do some YT viewing lol

essentially the top cap pushing down on the stem clamp is the adjustment.

Yes I understand the principal from road bike stems back in the 70's

The chances are it only needs a quarter of a turn to take up the slack ...if that!

 

[hunnymonster]

Back then it was all quill stems no?

 

[simon ess]

star fangled nut

That's no way to talk about about Asha.

 

[Asha]

Back then it was all quill stems no?

Possibly that is what they were called yes…..They worked when the bolt being tightened brought a wedged up into the stem which would splay out.

Over the years there have been a number of different ideas......some were difficult to work with ( removing / installing cups etc

 

[Asha]

That's no way to talk about about Asha.

just a "STAR" will suffice!

So who rattled you back to life?.......I thought you'd dissapeared into one of those many shadows that you used to photograph/ post

 

[Asha]

There are heaps of vids on YT on adjusting it - essentially the top cap pushing down on the stem clamp is the adjustment.

It's something like "Ahead headset"

Removing the star fangled nut is not something you should ever need to do

Here's one

View: https://youtu.be/ZK5u5ioZU8M

Sorted, thanks!

View: https://www.youtube.com/watch?v=0Gs3qTZ0H7c


Emailed the vid to my mate and put allen keys in my coat pocket ready to meet up with him at some point this weekend.