Gappy headset

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winjim

Smash the cistern
I've just put a brand new headset in and it's all gappy. It's kind of like the races don't match up with the bearings or something. I've tried bouncing it, jiggling it, rocking it, all the usual stuff to settle it in but no luck. FSA No11N, spec gives a 1mm gap betwixt fork crown and bottom cup but I've got about 3mm, plus a gap at the top. Any ideas or do I just keep jiggling?

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Slick

Guru
Same thing happened to me but it turned out I used the wrong bearings.

They were almost exactly the same other than a chamfered edge.
 

Slick

Guru
Yeah your probably right but mine was all brand new as well. It was just a slight difference between manufacturers apparently. I ended up having to make it fit by grinding down the plastic retaining washer.
 

KneesUp

Guru
Have you ridden it? I've just moved a headset from one frame to another - it was always 'gappy' at the bottom on the other frame so I assumed that was just they way it was - it has cartridge bearings so I wasn't too bothered. When I fitted it to the other frame it was also gappy, but as it had been the same on the first one I just ignored it. I rode it yesterday though and it has settled some, to the extent that I had to tighten it again last night.
 
OP
OP
winjim

winjim

Smash the cistern
Have you ridden it? I've just moved a headset from one frame to another - it was always 'gappy' at the bottom on the other frame so I assumed that was just they way it was - it has cartridge bearings so I wasn't too bothered. When I fitted it to the other frame it was also gappy, but as it had been the same on the first one I just ignored it. I rode it yesterday though and it has settled some, to the extent that I had to tighten it again last night.
Just one commute so far. I've been bouncing it around hoping that it might settle. I do live up a steep hill and the fork judders quite a lot under heavy braking. I'm putting this down to the disc brakes also being brand new but I want to make sure the headset isn't contributing to it.

Really daft question - are you sure the bearings aren't in upside down? BTDTGTTS
It's in as it was in the box, and according to the FSA spec the cups and bearings are identical top and bottom.

Did you fit a new crown race as well?
Yep. The only part that isn't brand new out of the box is the star nut.
 

Siclo

Veteran
I meant each bearing upside down, not the top in the bottom and vice versa. The angle on the internal radius should sit on the crown race for the lower bearing and the compression ring for the upper bearing, the angle on the external radius should sit in the cup. Don't bet on them being packed in the correct orientation.
 
OP
OP
winjim

winjim

Smash the cistern
I meant each bearing upside down, not the top in the bottom and vice versa. The angle on the internal radius should sit on the crown race for the lower bearing and the compression ring for the upper bearing, the angle on the external radius should sit in the cup. Don't bet on them being packed in the correct orientation.
Ah, gotcha. I don't think they can be mixed up like that. They're not proper cartridge bearings but what FSA are calling 'semi-cartridge', which appears to be ball and cage with a cover on top. I could take the thing apart and check.

Spec sheet attached...
 

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