Headset top cover not sitting right on Trek Procaliber

othello
othello Posts: 578
edited February 2019 in MTB workshop & tech
My daughter has a new Trek Procaliber 9.6, which we picked up yesterday. I swapped off the stock stem for a shorter one, but now I cannot get the headset top cover to sit correctly.

If you look at the image below, the top cover has a few mm gap between it and frame.

IMG_8702.jpg?dl=0

Image here https://www.dropbox.com/s/k14qrsd5ckq82bv/IMG_8702.jpg?dl=0


Tightening the top cap doesn't close the gap. I didn't disassemble the headset -- all i did was remove the stem and spacers and put the new one on. The fork did start to drop out of the frame and I had to push everything back in place.

Any ideas? Is there a spacer or something not aligned somewhere? I can't get back to the bike shop today and my daughter wants to ride tomorrow. This should be easy as I'm usually OK with bike maintenance!
Blogging about junior road bikes http://junior-road-bikes.tumblr.com

Comments

  • Sometimes there is a collar that sits inside the headset bearing and the forks come up through that and into the spacers etc.

    If your forks dropped out a bit, that may not be seated properly. On my bike the collar has a little cut in it (so it's not a complete "whole" circle), so it's a little springy and needs to be squeezed together to slot back in. Everything else then drops in on top.

    It's the split collar on the left in this pic:

    https://www.alibaba.com/product-detail/ ... 14661.html

    If it's not that, I've no idea!
    "Ride, crash, replace"
  • othello
    othello Posts: 578
    BillyCool wrote:
    Sometimes there is a collar that sits inside the headset bearing and the forks come up through that and into the spacers etc.

    If your forks dropped out a bit, that may not be seated properly. On my bike the collar has a little cut in it (so it's not a complete "whole" circle), so it's a little springy and needs to be squeezed together to slot back in. Everything else then drops in on top.

    It's the split collar on the left in this pic:

    https://www.alibaba.com/product-detail/ ... 14661.html

    If it's not that, I've no idea!

    Yes it has the split collar and that did pop out of the headset bearing stack as the fork started to slide down. I've pushed it back in but its not completely flat. Maybe that is why the headset cover won't sit down far enough. I'll pull the headset items apart and re-seat them and see!
    Blogging about junior road bikes http://junior-road-bikes.tumblr.com
  • whyamihere
    whyamihere Posts: 7,706
    Are you sure it was lower than that originally? There's always a slight gap there, because you don't want the cap rubbing against the frame, and it looks fairly even. That may be how it's supposed to be.
  • othello
    othello Posts: 578
    Tried again and there is still a small gap :(

    The cut collar is pushed right in and everything is aligned. I've tightened the top cap and the bars turn smoothly and there is no rocking. It is all working as it should, just with the small gap.

    Now I'm stumped!
    Blogging about junior road bikes http://junior-road-bikes.tumblr.com
  • slc123
    slc123 Posts: 407
    whyamihere wrote:
    Are you sure it was lower than that originally? There's always a slight gap there, because you don't want the cap rubbing against the frame, and it looks fairly even. That may be how it's supposed to be.

    I don't think it needs to be flush, I am pretty sure one of my bikes has a small gap and it's not an issue.
    Cannondale Trail 27.5 | 2015
    Titus El Chulo 27.5 | 2017
    Trek Slash 9 27.5 | 2015 (building)
  • The Rookie
    The Rookie Posts: 27,812
    A small gap is better than it rubbing as the steering is turned, I think that's as it should be on that bike.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • Could google for some photos of bike. Video below which , I think, shows gap you have at 1:14

    https://www.trekbikes.com/gb/en_GB/bike ... 6/p/21893/