Loose bars / headset

Dangermoss Posts: 6
edited August 2014 in Workshop
Hi all,

This is my first post, so please go easy on the newbie.

I've just taken delivery of a brand spanking new bike from Planet X.

I immediately got the bike out of it's box, positioned my bars and lightly nipped up the stem bolts.

The problem I have is that the bars are moving independently of the forks....

I tried loosening off the stem bolts and (lightly) tightening up the top cap bolt - no difference. :evil:

I don't want to be hanging off the bolts as, obviously, the stem's only alloy.

I've noticed the spacers also move with the bars. It's not excessively loose to the point you can spin it around, but it's not solid either. I definitely wouldn't want to ride it like it is.

Am I missing something glaringly obvious? :oops:

If it makes any difference the bike is a Viner Salviati and the stem is Planet X's own ultralight CNC 100mm jobbie.

Thanks in advance for the suggestions.


  • keef66
    keef66 Posts: 13,123
    No, I don't think you're missing anything.

    Tightening the top cap (with the stem pinch bolts undone) should only be neccessary to eliminate any play in the headset.

    Once you've done that you just need to tighten the pinch bolts on the stem so it clamps the steerer securely. It sounds to me that you just haven't tightened them enough.

    (Unless you have a 1" steerer and a 1 1/8" stem, but I'd have thought that would be obvious and the stem would be spinning...)
  • rafletcher
    rafletcher Posts: 1,235
    Just tigten it up more (I'm assuming no carbon fibre here, but if there is then some CF assembly paste is in order to help grip)

    1) loosen stem where it clamps around fork steerer.
    2) Tighten top cap bolt to eliminate play in the headset - to test, turn the front wheel so that it's a 90 dgrees to the frame and push forward and back (or put front brake on and do the same, but sometimes the wheel slips doing it this way)- you'll feel if there's any play - a slight "knock". Don't tighten too far such that the steering gets stiff to turn.
    3) Tighten stem bolts around steerer, aligning stem/wheel/top tube for "straight ahead" position.
    4) loosen top cap bolt, and then nip up just enough to stop it coming loose when riding.
  • keef66
    keef66 Posts: 13,123
    According to Planet X the Viner Salviati has a full carbon steerer, so maybe a tiny bit of carbon assembly paste would help the stem grip it securely without getting all gorilla on the bolts.

    TBH I'd be phoning Planet X and asking their advice
  • Sorry, I didn't clarify earlier; as far as i can tell the stem is gripping the steerer it's the steerer that is spinning independently of the forks.

    I'll give it another go when I get home, I didn't want to tighten it up too much as I'm paranoid about cracking something.

    I did tighten it all up a fair bit last night with no joy, I think I'll give Planet X a bell as suggested in the meantime.

    If all else fails I'll take it into my LBS in the morning.

    Thanks again.
  • rafletcher
    rafletcher Posts: 1,235
    Dangermoss wrote:
    Sorry, I didn't clarify earlier; as far as i can tell the stem is gripping the steerer it's the steerer that is spinning independently of the forks.

    Thanks again.

    It can't unless you've sheared off the steerer from the forks somehow - and then I'd expect (with a bit of a tug maybe) the forks would come out of the headtube. Easiest way to check is to remove the stem from the steerer along with any spacers (you may need to release the bars from the stem first to allow the stem to be lifted off the steerer), remove the top bearing for the headset, then pull the forks out downwards and see what happens!
  • Hmm, I'm certainly not that strong!

    Can you tell I don't really know what I'm on about? :roll:

    I normally get bikes pre-built from my local bike shop, this is the first time I've bought online.

    I don't really want to be pulling things apart, so I think I'll just leave it for my local bike shop to sort out :?

    Thanks for the suggestion.
  • keef66
    keef66 Posts: 13,123
    Take the top cap off (it serves no purpose once the stem pinch bolts are tightened) and turn the bars. You should be able to see if the steerer / bung is moving with them?

    As rafletcher says, if the steerer was somehow separate from the forks the forks would fall out when you pick up the front of the bike.

    And if the fork has failed catastrophically before you've even ridden the thing....

    Any sign of the box having been dropped??
  • Hi,

    No damage to the box whatsoever, I do have a vid of the issue but it's not uploading for some reason.

    I'll have a look tonight with the top cap off later on & post pics.

  • rafletcher
    rafletcher Posts: 1,235
    Whetever it is (and I'm dying to know!), with a a carbon steerer it's a god idea (like with carbon seatposts and bars) to use carbon assembly paste (like Vaseline with grit in!) to stop slippage under shock loads from potholes etc., so a good opportunity to see how your bikes headset goes together :)
  • Hi,

    Just an update to close;

    I removed my bars & stem as suggested and discovered a layer of very fine dust / swarf on the steerer.

    I cleaned it all off, refitted everything and tightened back up - all perfectly fine :)

    It was very fine stuff, it must have been from when they cut the tubes into shape or something?

    In any case, it's all fine now. Thanks for everyone's help, now out and about enjoying my new bike. 8)
  • keef66
    keef66 Posts: 13,123
    Oh I do like a happy ending!

  • rafletcher
    rafletcher Posts: 1,235
    Still think a little carbon assembly paste would add some security :D but glad you resolved it.
  • lapavoni10
    lapavoni10 Posts: 146
    Whenever brushing off carbon dust, DO NOT DO IT DRY !!!
    Wet it down with something, water or whatever. Maybe over paranoid, but I am guessing it will do your lungs no good whatsoever.