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Headset gap

Dandy Dan 69Dandy Dan 69 Posts: 45
edited April 2014 in MTB workshop & tech

I've just taken delivery of a Giant XTC composite. I've been putting it together this evening and I've noticed there's a gap between the top headset and the front of the head tube.


I've tried loosening the bolts on the stem and the bolt that goes down into the headset and readjusting the spacers and the stem, but the gap remains. There was a warning sticker on the frame about not over tightening the top bolt, so maybe I've been over cautious with that?

Anyone know why the gap remains?

Giant Trance 3 '08
Kona Lava Dome '96
Giant Alliance '08


  • jimothy78jimothy78 Posts: 1,407
    that picture makes it look like the upper cup of the headset isn't properly seated in the headtube (am I imagining it, or is there a (less obvious) gap at the back, between the headtube and edge of the cup?)
    Did you fit the headset cups, or were they pre-fitted?
  • They were pre-fitted.

    There's no gap at all at the back.
    Giant Trance 3 '08
    Kona Lava Dome '96
    Giant Alliance '08
  • jimothy78jimothy78 Posts: 1,407
    Hmmm, must be my eyes then (I'm looking between the bottom blue bit and the white bit, not between the two blue bits, where the gap shows at the front).

    The only other things i can think of is that either the top cover isn't perfectly flat (in which case the gap would move ifyou you turned it round), or the headtube hasn't been machined very well, and the top surface isn't perpendicular to the line of the steerer tube. can you take another photo, slightly wider, showing the whole assembly from the crown of the forks to the stem topcap.

    Also, can you confirm that there's the usual 2-3mm internal gap between the top of the steerer tube and the top of the stem (or topmost spacer, if there are any fitted above the stem)
  • BigAlBigAl Posts: 3,122
    Check what Jimothy says: does the fork steerer sit 2-3 mm below the top of the stem (or spacer if that's at the top)? It needs to be, so that when you tighten the top cap bolt it 'compresses' the whole headset/stem/spacer assembly and ensures there's no looseness. (Not too tight though - as this will hinder the bearings from rotating freely).

    Also, I'm wondering if there should be a rubber seal between the two blue parts.

    Similar looking headset in my Anthem - and there's definitely a seal ring in there
  • Cheers for the replies.

    I took it all apart again this evening and put it back again. There's now a small gap (1mm-ish) all the way round the headset. I've checked against a couple of other bikes and it's the same sized gap in the same place.

    There is/was a 3mm-ish gap inside the steerer but no washer. Not sure what I managed to do last night, but got it sorted this evening.

    Got Friday afternoon off and the weather is looking good so should hopefully be able to take it for its first proper spin then.
    Giant Trance 3 '08
    Kona Lava Dome '96
    Giant Alliance '08
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