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Star nut knackered!

Johnny NapalmJohnny Napalm Posts: 1,458
edited April 2012 in MTB workshop & tech
I swapped over my forks onto another frame to see how the 140s would suit and I noticed that two of the prongs (whatever they're called) have more or less corroded and come off. The star nut still seems pretty solid, but I will remove it if necessary. Do you educated bunch think it should be replaced, and if so, what's the easiest way of getting it out (might be worth noting that I don't have a vice at hand).
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Marin
SS Inbred
Mongoose Teocali Super

Posts

  • 386ka386ka Posts: 479
    Dunno what you mean by prongs really, but if it still serves it's purpose, then I would leave it. The stem does all the hard work, you can even remove the top cap after you preload the bearings and set the stem.
    Cheers.
    A much loved, Giant Trance X3 2010
  • Johnny NapalmJohnny Napalm Posts: 1,458
    Cheers.

    You know how they have the six prongs/arms/tabs (not sure of the correct terminology) - well, it's two of those that have corroded, so there are only four of them left.
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    Marin
    SS Inbred
    Mongoose Teocali Super
  • 386ka386ka Posts: 479
    Ah, those! :D I think that it's not a problem, as I stated above, the stem does all the hard work (make sure you tighten it properly). But you can wait for other opinions.
    Anyway, to remove the star nut, you should push it through the bottom of the steerer I think...

    Cheers.
    A much loved, Giant Trance X3 2010
  • Johnny NapalmJohnny Napalm Posts: 1,458
    Cheers, 386. :-)
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    Marin
    SS Inbred
    Mongoose Teocali Super
  • lugsey2k5lugsey2k5 Posts: 960
    Star nuts are about £2 either way so not really a costly thing to change. You can always just tap the star nut further down the steerer and put the new one above it unless you are concerned about the added weight!
  • oxocube1oxocube1 Posts: 651
    Yep the guys are right, just use a long instrument of some sort just to push the startnut out of the bottom of the forks. A long piece of PVC plastic piping would work or an extra long metal socket arm and just tap the top end of it with a hammer.
  • cooldadcooldad Posts: 32,599
    Often a hassle to knock it out the bottom of the steerer, just knock it down an inch and fit a new one - unless you are an extreme weight weenie.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • YeehaaMcgeeYeehaaMcgee Posts: 5,740
    As long as it's staying in place, just leave it. Like has been said, it's the stem that actually holds the tension anyway, the starnut is just used to preload the bearings - one the stem bolts are tightened id doesn't need to do anything.

    HOWEVER!!!
    Knocking the starnut down the forks is a pretty bad idea. It will leave score marks down the inside of the steerer tube, which can lead to fractures occuring at those points later in life.
    To be on the safe side, bend the prongs inwards with a long screwdriver, and either let it fall through, or pull it out of the top.
  • lugsey2k5lugsey2k5 Posts: 960
    As long as it's staying in place, just leave it. Like has been said, it's the stem that actually holds the tension anyway, the starnut is just used to preload the bearings - one the stem bolts are tightened id doesn't need to do anything.

    HOWEVER!!!
    Knocking the starnut down the forks is a pretty bad idea. It will leave score marks down the inside of the steerer tube, which can lead to fractures occuring at those points later in life.
    To be on the safe side, bend the prongs inwards with a long screwdriver, and either let it fall through, or pull it out of the top.

    So what about the first inch of the tube with score marks down it from where the star nut is installed? Even on aluminium steerer's it barely leaves scratches never mind score marks on them.
  • Chunkers1980Chunkers1980 Posts: 8,035
    Yes, but some taper to the bottom.
  • lugsey2k5lugsey2k5 Posts: 960
    Hence why i suggested just tap it down an inch. My fox's have a plastic plug type thing in the bottom so doubt i could get it out without removing that anyway.
  • YeehaaMcgeeYeehaaMcgee Posts: 5,740
    lugsey2k5 wrote:
    As long as it's staying in place, just leave it. Like has been said, it's the stem that actually holds the tension anyway, the starnut is just used to preload the bearings - one the stem bolts are tightened id doesn't need to do anything.

    HOWEVER!!!
    Knocking the starnut down the forks is a pretty bad idea. It will leave score marks down the inside of the steerer tube, which can lead to fractures occuring at those points later in life.
    To be on the safe side, bend the prongs inwards with a long screwdriver, and either let it fall through, or pull it out of the top.

    So what about the first inch of the tube with score marks down it from where the star nut is installed? Even on aluminium steerer's it barely leaves scratches never mind score marks on them.
    First inch or so is something we have to live with, and is ultimately an unusual place for the fork steerer to go. Almost all fork steerers taper inwards, and some are butted, so there's less material in the central section than there is at the top or the bottom.
    Also, the standard starnut location leads to scoring over the first inch or two - not the entire length of the steerer.

    Plenty of people do knock them down, and you can too. I'm just letting you know of the increased potential for failure later on. It's still your call whether you do it or not.
  • cooldadcooldad Posts: 32,599
    Live dangerously.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • Johnny NapalmJohnny Napalm Posts: 1,458
    Cripes!
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    Marin
    SS Inbred
    Mongoose Teocali Super
  • TorresTorres Posts: 1,266
    Just get the drill out Johnny :wink:

    Or just leave it, as long as your headset bearings are loaded properly (ie no play or sticky steering) then you're reet. :D
    What We Achieve In Life, Echoes In Eternity
  • supersonicsupersonic Posts: 82,708 Lives Here
  • DodgeTDodgeT Posts: 2,255
    And when the other prongs eventually corrode, it'll come out really easy. Then replace.
    As others have said, leave it for now.
  • valavala Posts: 197
    I followed this guide to remove a star nut.

    http://gearinches.com/blog/how-to/how-t ... a-star-nut
  • Johnny NapalmJohnny Napalm Posts: 1,458
    Being a lazy so and so, I do like the leave it option. There is no slack in the headset when loaded so I suppose I'll have to leave it then. :wink:

    Cheers, me dears!
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Marin
    SS Inbred
    Mongoose Teocali Super
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