Stem top cap and spacers above stem

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biwa
Posts: 198
Joined: Fri Sep 21, 2018 8:39 pm

by biwa

Sorry for the trivial/stupid question, but just realized both the stem top cap and the 10mm spacer on top of my stem are free to rotate while the stem bolt stays fixed. Is this normal or is it a sympton of something not tightened enough?

RECAR77
Posts: 48
Joined: Mon Jun 10, 2019 7:12 am

by RECAR77

Does the headset have play?

If yes then the headset wasn't adjusted correctly.

If no the headset adjustment bolt got loose after the stem was tightend. Just tighten it again so it's barely tight. It wont affect headset adjustment until you loosen the stem bolts.

Sent from my moto g(6) using Tapatalk


by Weenie


biwa
Posts: 198
Joined: Fri Sep 21, 2018 8:39 pm

by biwa

RECAR77 wrote:
Tue Jan 28, 2020 8:33 am
Does the headset have play?

If yes then the headset wasn't adjusted correctly.

If no the headset adjustment bolt got loose after the stem was tightend. Just tighten it again so it's barely tight. It wont affect headset adjustment until you loosen the stem bolts.

Sent from my moto g(6) using Tapatalk
No play from the headset. Just to clarify, if I tighten the top cap bolt now it won't increase the load on headset bearings because the stem bolts are tightened? As a side question, how do I prevent this from happening in the first place? Was there something I potentially did wrong before tightening the stem bolts?
Last edited by biwa on Wed Jan 29, 2020 12:46 am, edited 1 time in total.

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wheelsONfire
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by wheelsONfire

Top cap bolt is tightened (not stem bolts) until there is no play at headset or fork and fork crown race.
Then tighten stem bolts. Then it doesn't matter if the headset top cap is taken off. It is there for visual appearance.
Aka, it's not any danger if it come loose. Just tighten it to 1-2Nm.
Bikes:

Ax Lightness Vial EVO Race (2018.12.21)
viewtopic.php?f=10&t=156137
Paduano Racing Fidia (kind of shelved)
Open *UP* (2016.04.14)


Ex bike; Vial EVO D

DaveS
Posts: 2803
Joined: Fri Mar 24, 2006 1:26 pm

by DaveS

Loosen the stem clamp bolts and tighten the to cap to properly preload the headset bearings. Then retighten the stem.

Something moved to cause this problem. The expanding plug may have moved or if this is a new setup, the bearings may have settled a little. If it occurs again, the plug is slipping.

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ms6073
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by ms6073

Agree tha the expander inside the steerer tube has moved under torque and needs to be loosened, pushed back down, and then re-tightened to specified torque.
Michael - The Anaerobic Threshold is neither...

biwa
Posts: 198
Joined: Fri Sep 21, 2018 8:39 pm

by biwa

DaveS wrote:
Tue Jan 28, 2020 2:36 pm
Loosen the stem clamp bolts and tighten the to cap to properly preload the headset bearings. Then retighten the stem.

Something moved to cause this problem. The expanding plug may have moved or if this is a new setup, the bearings may have settled a little. If it occurs again, the plug is slipping.
Will try again, thanks. Just curious, what may cause the expanding plug to slip?

biwa
Posts: 198
Joined: Fri Sep 21, 2018 8:39 pm

by biwa

wheelsONfire wrote:
Tue Jan 28, 2020 10:47 am
Top cap bolt is tightened (not stem bolts) until there is no play at headset or fork and fork crown race.
Then tighten stem bolts. Then it doesn't matter if the headset top cap is taken off. It is there for visual appearance.
Aka, it's not any danger if it come loose. Just tighten it to 1-2Nm.
Sorry, meant to say tighten the top cap bolt (corrected now) after the stem bolts are tightened. I preloaded the bearings before tightening the stem bolts as you described, so is it correct to assume any further tightening (e.g. 1-2nm as you suggested above) of the top cap bolt afterwards will not change the load on bearings?

DaveS
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by DaveS

There is no reason to further tighten a top cap after preloading the bearings.

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wheelsONfire
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by wheelsONfire

biwa wrote:
Wed Jan 29, 2020 12:54 am
wheelsONfire wrote:
Tue Jan 28, 2020 10:47 am
Top cap bolt is tightened (not stem bolts) until there is no play at headset or fork and fork crown race.
Then tighten stem bolts. Then it doesn't matter if the headset top cap is taken off. It is there for visual appearance.
Aka, it's not any danger if it come loose. Just tighten it to 1-2Nm.
Sorry, meant to say tighten the top cap bolt (corrected now) after the stem bolts are tightened. I preloaded the bearings before tightening the stem bolts as you described, so is it correct to assume any further tightening (e.g. 1-2nm as you suggested above) of the top cap bolt afterwards will not change the load on bearings?
No, do not preload the top cap bolt more afterwards. If anything, after the stem is preloaded and torqued (fixed at the steerer tube), you can loosen the top cap bolt.
Just enough torque, so the top cap screw doesn't unwind.
The bearings can't be more or less preloaded once the stem is "fixed" at the steerer tube.
Bikes:

Ax Lightness Vial EVO Race (2018.12.21)
viewtopic.php?f=10&t=156137
Paduano Racing Fidia (kind of shelved)
Open *UP* (2016.04.14)


Ex bike; Vial EVO D

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synchronicity
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by synchronicity

Did you cut your fork steerer tube short enough?
If it's too long sometimes the headset cap can hit that, it feels tight but not actually compressing where it should...

Reno
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Joined: Fri Oct 25, 2019 7:00 am

by Reno

Sometimes top cap may hit the expander if you don't have correct size spacer underneath it. Then it will not do the job properly. So make sure the spacer above the stem is fully contacted by the top cap.

thedanplasse
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Location: Massachusetts

by thedanplasse

if it was hitting the expander the headset would have play.
2018 Specialized Tarmac Expert Sl5

Reno
Posts: 23
Joined: Fri Oct 25, 2019 7:00 am

by Reno

thedanplasse wrote:
Sun Feb 02, 2020 4:40 pm
if it was hitting the expander the headset would have play.
Most likely yes.

by Weenie


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