Viewing 26 posts - 1 through 26 (of 26 total)
  • Tech Problem- Star Fangled Nut
  • rossi46
    Free Member

    Any advice on how to remove a star fangled nut that gone wrong?
    Basically the star part is fixed in the fork just fine but the threaded part just spins, hence i can’t tension or loosen my Chris King top cap to remove the stem.
    As it’s a Chris King, i’m hesitating getting a drill out 🙄
    Iv’e tried tipping the bike upside down, removing front wheel, inserting an extension bar and whacking it with a big hammer but it won’t budge….

    Any other idea’s out there?

    Lifer
    Free Member

    Bending the teeth individually, difficult…

    kevin1911
    Full Member

    tap it down into the steerer tube and insert another?

    sweepy
    Free Member

    or tap it right out the bottom

    Lifer
    Free Member

    kevin1911 – Member
    tap it down into the steerer tube and insert another?

    His top cap is still attached

    bencooper
    Free Member

    Unless you can drift it all the way down and out the bottom of the fork, then a drill really is the only way – if you drill it, the two spring plates will separate and you can wiggle them out.

    soobalias
    Free Member

    as per kevin1911, bash it in further,

    probably dont bother trying to bash it right through as the steerer usually narrows at the fork crown end

    bencooper
    Free Member

    Dur, must read more carefully. The only other trick I’ve used is to get a steel tube just a little smaller than the bore of the steerer, and drive it up from underneath – this’ll force the prongs of the spring plate up and eventually force the entire thing out.

    soobalias
    Free Member

    as per kevin1911, bash it in further,

    EDIT: oh if the topcap is still attached, you are gonna have to get creative with a drill

    rossi46
    Free Member

    Thanks everyone… looks like the dreaded drill 😕
    Pray for Chris King 😉

    sweepy
    Free Member

    It can be as Chris King bling as it likes, but if its not working its just rubbish, drill it.

    soobalias
    Free Member

    wow, my editing is as good as your star fangled nut.

    rossi46
    Free Member

    The only other trick I’ve used is to get a steel tube just a little smaller than the bore of the steerer, and drive it up from underneath

    This first actually 💡

    kevin1911
    Full Member

    His top cap is still attached

    Oh, right, I see…

    Unless you can get in from the bottom to press something against the thread of the centre bit of the star nut to stop it turning, I reckon drilling might be your only option.

    bencooper
    Free Member

    A good way to do it, if you get a long bit of tube, is instead of drifting up you put it on the floor so the tube is on the floor, going up through the steerer, and resting on the bottom of the star nut. Now set about the top cap with a rubber mallet.

    Make sure there’s some space between your fork dropouts and the floor, of course.

    rossi46
    Free Member

    press something against the thread of the centre bit of the star nut

    Mmmmmmmmmmmmmmmm ………… that could work. Good thinking batman 💡

    rp16v
    Free Member

    Smack the crap out of it from underneath itl ither come out or ul bent it to the point u can undoo the bolt

    theotherjonv
    Full Member

    if you pull the bolt upwards at the same time as unscrewing, does that give it any purchase against the rest of the SFN?

    rossi46
    Free Member

    if you pull the bolt upwards

    Nope, still spins….

    Smack the crap out of it

    Delicately put 😉

    Tracker1972
    Free Member

    If you have already battered 7 shades out of it from below you may have deformed the end of the bolt so I doubt you will be able to get enough purchase with wiggling and pulling to get it out. Really like the idea of the smaller tube in from below and just blast it all out in the new tube. Bet you have your cut the bolt though…

    walleater
    Full Member

    Just bashing it upwards never really works very well as they are not designed to go upwards. But if you get a really big long screwdriver, you can go at it from underneath, but hit the end of the tabs to punch them away from the steerer rather than hitting the middle bit. You’ll end up folding the SFN up.

    Also, while not relevant in this case, but smacking the SFN down through the bottom of the fork sometimes doesn’t work because the steerer can be internally butted.

    dantsw13
    Full Member

    Could you lose 5-10 mm from your steerer? Hacksaw between 2 spacers, through the steerer and bolt.

    If not, maybe get creative with a Dremmel/hacksawon the top cap until you can get the bolt out. New top cap is peanuts.

    khani
    Free Member

    Try an electric drill with an Allen bit, the speed can enough to undo it sometimes…

    Nobby
    Full Member

    I’d favour a long screw driver from underneath bending each tab individually.

    Edit: Unless you have a 20mm hole saw and an extension bar?

    bigblackshed
    Full Member

    Drill the bolt out. Cobalt drill bit if it’s a steel bolt. Then knock the SFN down into the steerer tube and leave it in there. Then fit a Hope Hed Doctor and never worry about it again.

    This won’t work if you’re a weight weenie. You will always know that there is 20grams of SFN in your steerer that will be slowing you down. 😉

    PiknMix
    Free Member

    Long shanked flat bladed screwdriver from underneath on each of the flanges one at a time to bend them, I had to do this on a pair recently, I don’t drill any of my bike stuff so this was my only option, Took ages to do it carefully though.

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