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Headset/bearings problem on Carrera mountain bike

I've bought a used mountain bike that had a stiff head so took apart the headset to inspect and the bottom bearings/cage (top is sealed unit) were pretty trashed. I bought new 5/32 bearings but the race and bearing will not seem to fit back into the bottom of the headset. Strangely the race will on its own and so will the bearings, but the bearing on the race it simply won't push in. Any ideas would be greatly appreciated.

Posts

  • scuzzascuzza Posts: 16


  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    Don't quite know what you have on either side of the bearings on the second picture? The one on top isn't necessary and the one on the bottom if it's the fork crown race should be pressed and fully seated on the bottom of the fork steerer tube.

    Apply grease around the bottom headset cup race and grease the caged bearings. Push the caged bearings directly into the bottom cup.

    May be easier to turn the bike upside down, if not the grease should hold the caged bearings in position.

    Insert the steerer tube up (or down) through the head tube to sandwich the bearings in between the headset cup and fork crown race and re assemble.
  • scuzzascuzza Posts: 16
    Thanks very much for the reply, here's a couple more pics with the race/retaining clip apart.


  • No worries.πŸ‘ Give the bottom cup a good clean and check it's got a nice smooth surface before you apply the grease.

    The race on your hand looks like the fork crown race so give that a good clean and check that's smooth too then pressed it down onto the bottom of the fork steerer.

    Don't know what the thin split washer/retainer is for or where it goes?
  • scuzzascuzza Posts: 16
    I've removed that retaining ring but the problem is that I can push the bearings into the tube no problem, and also the race, but the two won't go in together, tried on at a time or as a unit like my first pic. I started to wonder if the replacement bearing were slightly larger than the existing. Possibility ?
  • scuzzascuzza Posts: 16
    My very first picture is pushing the bearings/cage/race hard into the bottom of the tube - it's as far as it will go when I put int back together and tighten the headset
  • 5/32 is the standard size and should fit fine. Is the cage bent or interfering with the fit?
  • scuzzascuzza Posts: 16
    Doesn't seem to be - the censored must go in somehow as it came out, it's not a bloody baby ! :-)
  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    Lol! πŸ˜€ The cage isn't necessary and you could just use the bearings on their own if you had a few more to make up the space the cage gaps leave. Do you have enough to fit all around the race leaving a two ball width gap?

    If you fit the balls first and the crown race onto the the forks it might just make the difference when it all pushes together.

    Sorry it's been a few years since I've done a loose ball bearing headset but haven't had an issue when fitting the crown race on the steerer first and never tried to test fit like you did in the first picture.
  • scuzzascuzza Posts: 16
    Thanks for that, I might give that a go with the individual bearings.
  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    Whether you try with or without the cage it's worth fitting the fork crown race and see how it goes. It may just add the little extra force you might need and the bearings could just pop into place. Good luck @scuzza! πŸ‘
  • scuzzascuzza Posts: 16
    Morning :-) What hold the bearing in place, as it's not like a channel that you drop the, in, just smother them in grease so they stick to the race and just roll out ? I did a bit more research last night and there does seem to be a slightly different outside radius of 5/32 bearings/cages

    Whether you try with or without the cage it's worth fitting the fork crown race and see how it goes. It may just add the little extra force you might need and the bearings could just pop into place. Good luck @scuzza! πŸ‘

  • scuzzascuzza Posts: 16


  • scuzzascuzza Posts: 16

  • Morning. Yeah the standard size is 5/32 for headset bearings. The cage performs no function except for easier installation and avoid losing them when they're loose, easy to do.

    A thick layer of grease around the inside of the bearing cup race at the bottom of the headtube will hold them in place while you insert the forks. The bearings will obviously stay put better if you turn the bike upside down so easier to do it that way.

    Once steerer is fully inserted and the bearings are contacted on both sides all should fit snug but also friction free.

    Just take care that the bearings stay put as you slide the steerer tube through or you won't get it together properly.

    I've seen a great You Tube video somewhere of the very thing you're doing so I'll try and find it and post a link soon.πŸ‘
  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    This will help and worth a watch:-

    https://youtu.be/Uq3LNMfedl8

    If link doesn't work type on You tube search 'Replace caged bearings with loose bearings on a bike headset' by R.J. The Bike Guy.
  • scuzzascuzza Posts: 16
    you're a star, thanks so much :-)
  • scuzzascuzza Posts: 16
    The ploy thickens !! see pics, same problem, but then....I found a couple of the old bearing on the floor, they are MUCH smaller ! I though 5/32 was just the standard, didn't even know small ones existed...
  • scuzzascuzza Posts: 16

  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    WTF! πŸ‘€ Bearings come in multiple sizes from tiny to huge. Never known any standard 1,1/8 headsets (which I'm sure you have) to use a different size to standard, it's the same as cup and cone front or rear hub bearings, which are a universal diameter.

    The ones you've found are possibly worn down but never seen them wear so much smaller before.

    So the steerer won't go through the headtube or is too tight, a complete no go?
  • scuzzascuzza Posts: 16
    Yeah, it simply won't push in, as if the bearing are too big. As it's a halfords bike, they seem to only do one set of replacement bearings for their bikes so ordered them (here later today) - I'm hoping they come up a tin bit smaller or the cage is bit smaller and fits... I did think maybe they have worn but some were still perfectly round - very strange indeed. I wonder if the person before me had a fiddle and fitted some dodgy stuff, hence them moving it on !
  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    Suppose it's possible but can't think what the previous owner could have done or fitted to alter it?

    All reasoning suggests the replacements you've got coming will be exactly the same 5/32 size and won't solve the issue.

    Clutching at straws now but any way to identify the current headset, markings etc?

    Any idea on the exact model and year for your Carrera to double check stock components via spec sheet?
  • scuzzascuzza Posts: 16
    It was sold to me as a 2019 Carrera Hellcat - couldn't find any specs online, maybe I'm just not looking in the wrong places
  • reaperactualreaperactual Posts: 1,163
    edited February 2021
    So I've looked up spec on the 2020 version. Semi intergrated 1,1/8 headset. Standard widely available for a lot of bikes.

    Seen pics of 2019 limited edition in green and black. No reason to assume the headset you have isn't the same as the 2020 version and both have the same forks fitted.

    So the 5/32 bearing should fit but they don't, who knows why, no clue myself.

    You could try random sized smaller bearings but I couldn't even guess which size to try.

    To dot the i's and cross the t's how about a pic of the steerer tube where it joins the fork crown. A rough measurement of the inner diameter of the bottom of head tube not counting the cup that's pressed in, should be 44mm wide.

    Then maybe consider a new good quality headset or at least a new bottom headset assembly? More involved but easily doable with a home made press and a screwdriver. Might as well fit a sealed bearing if you're gonna go to the trouble which will probably outlast the bike for around Β£20ish? πŸ€”

    https://www.chainreactioncycles.com/brand-x-headset-44iiss-sealed/rp-prod130946




  • mully79mully79 Posts: 863
    i thought the only standard on head sets was theyre all freaking different. why else have so many stupid sizes ?

    I've popped the bearings on a Jamis and they were tiny just like your picture.
  • scuzzascuzza Posts: 16
    i've changed for 1/8 bearings and goes and and works fine ! Thanks so much for all your help
  • Good work @scuzza. Congrats on working it out yourself in the end, lol!πŸ˜„πŸ˜ŽπŸ‘
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