B*stard Headset Still Knocks!!!!!

steve23
steve23 Posts: 2,202
edited November 2008 in Workshop
right.....

my old headset was buggered so i got a brand new one, a cane creek.

i installed it a few months ago, and it was great, until it started knocking!
so i stripped it down again, and the crown race was not on perfectly, so i re did it so it was nice and tight. put it back together, and then it worked!

now again it came loose a few weeks later, i tightened everything up and it was ok, not perfect but better!!!

just come back after a 2hr ride, and its knocking like hell!!!!! stripped it down, and i just cant see what it is! there isnt any cracks anywhere and everything seems to be fitted correctly and properly!!! as ive checked everything 3 or 4 times!!!

anyone any ideas? thanks!
_______________________________________________________________________________________
If You Can't Cut It With The Big Dogs, Then Don't Pi$$ Up The Tall Trees!

Comments

  • If it's a carbon steerer you're using, my money would be on the bung not gripping correctly and hence causing the headset to loosen. See if there's a bung available for the exact fork type you're using. Good luck.
  • trekvet
    trekvet Posts: 223
    This may hurt.

    Why didn't you fit the crown race properly in the first place?

    Why do you keep stripping it down when it knocks?

    If the knocking was merely proper bedding-in which you kept missing, why didn't you just adjust it up correctly?

    If you adjust it up but found steering tight in one place - loose in another, it means ball cups askew. Take it to bike shop.
    If you adjust it up and it correct but knocks it could be ball cages upside down. Take it to bike shop.
    If you adjust it up and it correct but knocks later could be AHead stem or cap or star washer loose. Take it to bike shop.
    When you checked out above:
    If you adjust it up and it correct but knocks later, adjust again without stripping as my be just bedding in.
    The Wife complained for months about the empty pot of bike oil on the hall stand; so I replaced it with a full one.
  • steve23
    steve23 Posts: 2,202
    i stripped it down to check that it wasnt anything that i had done incorrectly. it wasnt.

    ive ordered a new steerer bung, will see if that helps!!!
    _______________________________________________________________________________________
    If You Can't Cut It With The Big Dogs, Then Don't Pi$$ Up The Tall Trees!
  • Steerer bung? Are we talking quill stem or AHead?
  • nicklouse
    nicklouse Posts: 50,673
    all the bund is for is allowing something to allow the preload to be added. once the preload has been set to get the bearings right it can be removed as the stem holds it all together (A-headset set up)

    are you sure the steerer is not bottoming out on the top cap?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • pretty much be certain than the bung is not holding, meaning the headset will fell knocky.
    just need a new one that grips, or careful how you tighten the old one, and make sure you tighten it whilst your stem is on...
    63 miles to go and the break is up the road
  • andyrr
    andyrr Posts: 1,828
    Couple suggestions :
    Make sure that there is s couple mm's clearance from top of fork steerer to the top of the stem so that the top cap isn't bottoming out on the steerer - seen this myself a few times. Have you a spare spacer to try to up the stem a little bit ? Could be that the new headset has a lower stack-height
    Check the installation of the headset : I had an old headset (so shouldn't apply here really) that the cage broke up and when I took it to bits and greased it I hadn't realised that one of the balls had popped out of the cage so I tightened it up and it initially felt ok but it very quickly loosened.
  • presumably your heatset tube has crane creek fitting and not campag or FSA type?
    Theuy are different.
    What was your old headset?
  • wilwil
    wilwil Posts: 374
    If its OK when you leave the house and then comes lose, it isn't the bung. The bung/expander is redundant after you have tightened the stem onto the steerer. It just loads the bearing whist you tighten the stem.

    With this in mind make sure you tighten the bung before you tighten the stem

    Have you got grease on the steerer? There shouldn't be any.

    Is the stem tight enough? Be carefull you don't want to crack the steerer but it may not be tight enough.

    Make sure the top bolt of the stem is not above the top of the steerer. Its better on carbon steerers to have a spacer above the stem.

    Make sure you haven't already cracked the steerer

    Try carbon assembly paste where the stem grips the steerer.

    As previously mentioned, ensure there is at least 2-3 mm of stem or spacer above the top of the steerer.
  • steve23
    steve23 Posts: 2,202
    cheers for all of the advice, i will try the new bung when i get and and see if that helps!

    as for leaving enough space, i have done!!! there is a few mm gap above the steerer tube!
    _______________________________________________________________________________________
    If You Can't Cut It With The Big Dogs, Then Don't Pi$$ Up The Tall Trees!
  • There are basically 3 types of Aheadset:

    1. Integrated.
    whose bearings fit inside the frame tube for a 46mm OD headtube.
    Of the integrated headsets there are two sub types: Campagnolo and Crane creek.
    Campag type have their bearings at 45x45 deg angle
    Crane Creek have them at 36 x 45 deg angle

    2. Internal headset (or Zero Stack or low profile or semi integrated)
    These are for 50 mm OD headtubes and have a lip on the bearings that are pressed into the frame.

    3. Threadless Aheadsets
    These unlike the other two have fixed cups pressed into the frame and the bearing sit inside the fixed cups.
  • steve23
    steve23 Posts: 2,202
    fitted the new bung tonight, seems better, but i will need a ride on it to see!!!

    will have to wait until saturday to see if its worked.....
    _______________________________________________________________________________________
    If You Can't Cut It With The Big Dogs, Then Don't Pi$$ Up The Tall Trees!