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Disk Bolts

silverknellsilverknell Posts: 183
edited April 2008 in MTB workshop & tech
I am having trouble getting my 6 disk bolts out of the rotor. I have used everything bolt remover i have and none of them fit, they either are too big or they round the bolts. So now they are all rounded. Is there a way to get them off? I have an aztez wavy rotor and i want to put that rotor on the back.

Many thanks.
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  • if they are all rounded off you will need to use a small hacksaw to cut a slot in the bolt head and remove with a slotted screwdriver carefully. I take it you were using a proper sized torx bit normally T25 to remove them?
  • silverknellsilverknell Posts: 183
    Part of the Left-handed CommunityTM
  • fizikfizik Posts: 247
    Its pretty easy to round them off, especially with cheap tools, do as artillery dave says. If they are too tight trying to screw them out with the screw driver get a smaller flat headed screw driver and put it to the outside of the slot and then use a hammer and tap the bolt round until its loose enough to screw out. Depending on how tight it is you may have to hit it quite hard.
  • silverknellsilverknell Posts: 183
    So use a screw driver to put in the bolt then hit with hammer till it comes loose?
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  • fizikfizik Posts: 247
    1) use a small hacksaw, cut a slot across the top of the offending bolt.
    2)As artillerydave said then try unscrewing the bolt with a flathead screw driver

    If the bolt is too tight, which maybe it is seeing as its rounded then imagine this.

    with the screw driver and hammer you need to hit the bolt about 45 degrees to the horizontal and also angled towards the centre of the bolt slightly with the screw driver end firmly in the slot, but it needs to be as off centre on the bolt as possible to create the turning moment.

    This is with the wheel in a flat position

    If you cant get it out just take to lbs and they will sort it pretty easily.
  • zaynanzaynan Posts: 180
    I ruined a hub trying to sort out the problem you have (sorry, you probably didn't want to hear that!). The forum has offered good advice but be warned that once you have cut a slot in the bolt head you can actually shear off the bolt head either side of the slot you have cut! It DOES depend on how tight the bolts are and how much (if any) locking compound was put on the threads to start with. GOOD LUCK! If you change your rotors regularly it might be investing in some titanium rotor bolts. In theory they may not round off like the ones made of cheese that most rotors come with - however I don't have any personal experience of using Ti bolts.....
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  • fizikfizik Posts: 247
    Zaynan is right, when cutting the slot, do not cut it all the way down to the disc rotor or it will snap off when you use the hammer. Cut it just enough to get the end of the screw driver in, doesnt have to be very deep.
  • silverknellsilverknell Posts: 183
    Part of the Left-handed CommunityTM
  • nicklousenicklouse Posts: 50,675 Lives Here
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  • silverknellsilverknell Posts: 183
    Ahh thanks.
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  • ride_wheneverride_whenever Posts: 13,279
    Didn't someone mention reverse screw drill bits, sounds perfect...
  • 26 to Life26 to Life Posts: 194
    They're called easy outs and they basically put a left handed thread inside your bolt so when you turn it, you will either tighten your grip on the broken bolt, or unscrew the bolt.

    They're a great idea, but not for the mechanically inexperienced. You could end up making everything a lot worse if you fail to get the hole in the centre of the thread, or if it isn't quite straight. This will be especially hard to get right in this case because the small diameter of the threaded section in disc rotor bolts leaves very little room for error.

    If in doubt, get it to a shop, it won't cost a lot and could save you the cost of a new hub and wheel build.
  • silverknellsilverknell Posts: 183
    thanks for the advise guys, unfortuanatly i can't get them off or even loosten them. I think the bike shop is the way to go.
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  • GHillGHill Posts: 2,402
    Could be they have some pretty strong thread lock on, you might be able to loosen it by soaking them in hot water. Or you might just make a mess :wink:
  • silverknellsilverknell Posts: 183
    Ha ha, lol, thanks, i might try that..but i reckon i might just make a pretty good mess.
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