Curse of the Torx?

DanDax1990
DanDax1990 Posts: 1,201
edited February 2013 in MTB workshop & tech
Second time I've had to take rotors off... Second time I've had problems with the bolts.

The rear bolts came out fine but 3 of the bolts on the front wheel won't come out and have started to round off. What am I doing wrong?

The first time I had issues I took the wheel to my LBS and he got the bolt out and replaced them with Hope titanium bolts, saying they were the best bolts for rotors. These are the bolts I'm having problems with.

Is it because they're too tight? Too much thread lock?

Also, what's ny best bet of getting the culprits out? And... Which boots should I replace them with?

Cheers guys.

Comments

  • The Rookie
    The Rookie Posts: 27,812
    Steel is better than titanium.

    Poor fitting torx bit sounds the obvious thing, I've only ever had one round off and that was a cheap allen headed one.

    I just replaced the rear bolts on my commuter after 2 years and pretty rusty, popped out no issue.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • DanDax1990
    DanDax1990 Posts: 1,201
    I checked the bit before hand, seemed a nice fit.

    What's the best/easiest way to remove the ruined bolts?
  • if the torx bt has rounded the bolt out the possibly cut a slot over it and use the largest screw ive you have, but, if they have rounded off on a torx bit chances are they wont move, try a say of plusgas on the inside of the flange to get at the threads,
    its no down to the 'snugness' of the fit but he quality of the torx bit your using, same with allens, i use my park pocket set (aws10 i think it is) fr everything, its built countless bikes, used on many rep[airs out and about and still spot on,
    Timmo.
    After all, I am Cornish!
    http://cornwallmtb.kk5.org/
    Cotic Soul, The bike of Legends!:wink: Yes, I Am a bike tart!
    http://www.bikeradar.com/forums/viewtop ... 1#16297481
  • Levi_501
    Levi_501 Posts: 1,105
    Some designs of Torx bits are not well manufactured.

    Many (esp cheaper ones) have the corners of the drive splines rounded off, see picture

    http://upload.wikimedia.org/wikipedia/c ... rivers.jpg

    Therefore, when a rotational force is applied, the drive is only passing through some og the drive spline and can round out.
  • DanDax1990
    DanDax1990 Posts: 1,201
    I think the LBS over tightened them way too much...
  • supersonic
    supersonic Posts: 82,708
    The LBS want's shooting, titanium has to be used with care. Are NOT the best. They have a habit of binding to the hub.
  • The Rookie
    The Rookie Posts: 27,812
    Ti is best for making a crazy profit from though, especially at shop prices!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • DodgeT
    DodgeT Posts: 2,255
    Mole grips should be your friend. They got a well mangled disc bolt out for me once.
  • So in one sense, they were indeed the best bolts, just not for the customer.

    Personally I'd file a slot in the bolt head with a dremel, apply a bit of plusgas and then some "careful" use of an impact driver.
  • pilch
    pilch Posts: 1,136
    Slightly bigger allen bit, carefully tap in then undo as normal
    A berm? were you expecting one?

    29er race

    29er bouncer
  • pilch wrote:
    Slightly bigger allen bit, carefully tap in then undo as normal

    does that work? I know it can work the other way around ie. slightly larger torx bit in a rounded hex bolt.
  • pilch
    pilch Posts: 1,136
    pilch wrote:
    Slightly bigger allen bit, carefully tap in then undo as normal

    does that work? I know it can work the other way around ie. slightly larger torx bit in a rounded hex bolt.

    Yes, I've done it myself... tapping it in helps free it, then it effectively jams in the top of the bolt head then you can unscrew, if it doesn't work you can always cut a slot as described above
    A berm? were you expecting one?

    29er race

    29er bouncer
  • DanDax1990
    DanDax1990 Posts: 1,201
    Well me and my brother was at it for a good few hours, Managed to remove one but two were still well and truly stuck...

    We tried everything, Bigger torx, flat head, drilling the head and then mole grips. Nothing worked.

    I got the discs off after I drilled the heads of the screws off but because the mole grips weren't working I had to try drill them out which I knew wouldn't work. Ended up just boring the original holes bigger and not drilling through the ti screws that were still in so my front hub is either going in the bin or just use it with 4 screws instead of 6.

    What do you guys think about the 4 screws instead of 6? I've got a new wheelset I was just wanting to keep these for next winter...
  • Can you not just rethread the New size holes you've drilled? Or are they Much bigger?? Possibly marginally out of balance If both are close to each other,
    Timmo.
    After all, I am Cornish!
    http://cornwallmtb.kk5.org/
    Cotic Soul, The bike of Legends!:wink: Yes, I Am a bike tart!
    http://www.bikeradar.com/forums/viewtop ... 1#16297481
  • DanDax1990
    DanDax1990 Posts: 1,201
    I need to drill the holes to get the threaded parts of the screws out but when I try, because the screws are a much harder material than the hubs, it's just boring the original holes bigger and not doing anything to the screws that are stuck inside. If that makes sense?
  • stubs
    stubs Posts: 5,001
    Too late now but you should have taken hub back to the shop. He probably didnt prep the threads before fitting them. Titanium as you have found is a bastard to drill it just screws up the drill bit.
    Fig rolls: proof that god loves cyclists and that she wants us to do another lap
  • DanDax1990
    DanDax1990 Posts: 1,201
    It's only my front hub, I wasn't too bothered because I was going to keep it as a winter wheel but got plenty of time to get a cheap one for next year :)
  • peter413
    peter413 Posts: 5,120
    If it's two holes opposite each other there shouldn't be any problems. I've seen a few people running their bolts 2x2 and they haven't died.
  • DanDax1990 wrote:
    We tried everything, Bigger torx, flat head, drilling the head and then mole grips. Nothing worked.

    Did you try plusgas and filed slot + impact driver?