Headset adjustment advice please

[bad boy]

Hello All,

Following on from my post the other week about my carbon steerer.

I have needed to re-adjust the pre-load on the headset after noticing some play.

With the stem clamp bolts loose I adjust the top cap which sits on top of a 5mm spacer and this is fine I can remove the play no problem.

When I then tighten the stem clamp bolts its as if some play returns. I can if I try just about turn the top spacer by hand above the stem ?.

I cant turn the bottom 15mm spacer below the stem thats rock solid just wondering if the same should apply to the one above the stem as im not sure how I can solve this its a new bike so would have thought everything is in working order ??

Cheers

 

[Smokin Joe]

With tapered cartridge bearing headsets when you have turned the bolt enough to remove the play you then need give another quarter or half a turn to settle the bearing into the frame recess, it will still turn freely and smoothly. If you adjust it only to the fine line that just removes the play it will be forever coming loose.

 

[bad boy]

Thanks smoking Joe

It's really tight to turn I've got the play sorted now but when all tightened up stem and all the top spacer can be turned just about is this ok ?

 

[Smokin Joe]

Don't worry about the spacer, does the bike steer freely? When you lift the front wheel and begin to incline the bike the bars should turn on there own, though there will be slight resistance because of the cables.

 

[Cubist]

Thanks smoking Joe

It's really tight to turn I've got the play sorted now but when all tightened up stem and all the top spacer can be turned just about is this ok ?

This worries me. The top cap bolt shouldn't be very tight to turn once you've tightened the stem bolts. Start again, but this time undo the top cap bolt, loosen the stem bolts. Check the way the bearings run as Smokin Joe describes. Then a half turn at a time tighten the cap bolt until the play disappears. Now push down on the stem and tighten the stem bolts alternating between them. Once they are torqued up properly tighten the cap bolt a final quarter to half turn. Forget the top spacers, that don't affect bearing play in any way

 

[P.H]

Once they are torqued up properly tighten the cap bolt a final quarter to half turn. Forget the top spacers, that don't affect bearing play in any way

What?? Why??? Once the stem is tightened the top cap isn't doing anything, you could remove it if it wasn't for the hole it'd leave. Look at the Park Tools site for maintenance tips;


http://www.parktool.com/blog/repair-help/threadless-headset-service#adjust

Check that you're not clamping the stem too tight and slightly deforming the steerer, the bung you're using should prevent this, make sure it is positioned where you are clamping. I'd also double check that it is tight enough before you tighten the stem and the gap between steerer and spacer is enough. Then if you're sure the bearings are under to proper load, forget about it.

I've just tried to move the spacer above the stems on my bikes, one I can, two I can't, I wouldn't have known that without this thread...

 

[bad boy]

This worries me. The top cap bolt shouldn't be very tight to turn once you've tightened the stem bolts. Start again, but this time undo the top cap bolt, loosen the stem bolts. Check the way the bearings run as Smokin Joe describes. Then a half turn at a time tighten the cap bolt until the play disappears. Now push down on the stem and tighten the stem bolts alternating between them. Once they are torqued up properly tighten the cap bolt a final quarter to half turn. Forget the top spacers, that don't affect bearing play in any way

I have always loosened the stem clamp bolts then adjusted the top cap then nipped up the clamp bolts as you describe alternating between the two.


So basically the top cap bolt can be sort of loose after tightening the stem is that what your saying ? if so thats sort of reassured me as I thought it had to still be solid after tightening the stem ?.

Is it true then when people say you can remove the top cap after clamping the stem is it with this in mind ?

Thats really interesting thank you for that advice. I think I got it right was just worried about the top spacer as I noticed it could be turned by hand. I have not tried to tighten the top cap after the stem it was just the spacer I noticed could move.

There is no bearing play when I lift the front the wheel turns freely all beit the cables hinder this slightly to the left and steering feel light and fine.

Do I have a problem or am I just worrying ?

Thanks

 

[PpPete]

and someone on here was trying to tell me not long ago that these things are simpler than quill stems ?

 

[GrumpyGregry]

the stem cap and bolt that goes into the star fangled nut are there only to preload the bearing before you clamp the whole shebang up using the stem and its bolts. The stem and bolts do all the work and bear down on the bearing via the lower spacer. Once the stem is done up the cap and bolt are there for decorative purposes and are not needed (until something wears or shifts).

 

[bad boy]

the stem cap and bolt that goes into the star fangled nut are there only to preload the bearing before you clamp the whole shebang up using the stem and its bolts. The stem and bolts do all the work and bear down on the bearing via the lower spacer. Once the stem is done up the cap and bolt are there for decorative purposes and are not needed (until something wears or shifts).

Thank you everyone for the help im reassured that I shouldnt be worried about the spacer.

 

[Cubist]

What?? Why??? Once the stem is tightened the top cap isn't doing anything, you could remove it if it wasn't for the hole it'd leave.

The final half turn is to stop it working itself loose and getting lost. How would you adjust the bearings next time?!

 

[Smokin Joe]

and someone on here was trying to tell me not long ago that these things are simpler than quill stems ?

A lot simpler.

Bearing adjustment does not have to sit on a knife edge of adjustment like traditional headsets.

 

[bad boy]

done 10 miles this morning on it just to see and it feels ok has not loosened up so hopefully it can go back in the shed for a while until my next race !.

Any more problems I think ill try a higher spacer on top or a different bung that allow me to reposition it, as the one i have lipped over the top of the steerer.

Thanks

 

[fossyant]

A lot simpler.

Bearing adjustment does not have to sit on a knife edge of adjustment like traditional headsets.

Quite.

3 traditional headsets and 1 ahead system - the ahead is a doddle - so much so you really don't mind stripping and re-greasing. Despite the 'looks' they are much better for maintaining.

 

[Zoiders]

After having heard the same headset questions about a squillion times I have come to the conclusion that if you are going to get the head set adjustment right you will have figured out how works on your own and you have the feel for how tight it should be without trying that hard.

When it needs the lengthy on-line explanations you kind of get the impression that they would be much better off popping it in at a LBS.

I think a lot of mechanical stuff is almost an artistic talent and it largely can't be taught - you either have it or you don't.