Disc Rotor bolts backing off

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Disc Rotor bolts backing off
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Posted: Aug 7, 2009 at 6:59 Quote
I have a 6ish month old crossline wheelset, and two of the bolts that hold the disc in place on the front wheel are really loose. I think it may have been a result of me over tightening the bolts, which led to some material coming out of the threaded holes. So i know WHY its like that, but is there anything I can use to secure the bolts, like loctite or something?
flag bikerkid13
Posted: Aug 7, 2009 at 7:02 Quote
Yeah just loctite that stuff up same thing happened to me. Havent had any problems since.
flag sfsdspecconcept
Posted: Aug 7, 2009 at 7:04 Quote
be sure to use BLUE loctite, it should solve everything
flag almostwise
Mod
Posted: Aug 7, 2009 at 7:13 Quote
If you've cross-threaded it, you might be able to re-tap it. Locktite will hold the bolts in but if the thread in the hub is knackered they won't hold any torque. Take it to your LBS and ask their advice. If your rotor comes off mid ride, well it wouldn't be fun. You might be able to claim on the warranty.
flag GenericName
Posted: Aug 7, 2009 at 7:19 Quote
How long are the rotor bolts? The same thing happened to me a few years ago, and I managed to get hold of some longer bolts which reached the intact thread deeper in the hub.

Just be careful putting these in, if you overtighten them again you'll need to retap the threads/buy a new hub.
flag xcrisx
Posted: Aug 7, 2009 at 7:23 Quote
I shouldnt think he would be able to make a claim under warranty as its neither a mechanical or a design flaw that has shown up under normal use, but he has damaged them on his own.

it shouldnt be a problem to re-tap them though. if you cant and you need to loctite them in place, get a matchstick and break it into slivers and put one into each hole before the bolts. then, when you screw them back into place they will be forced into the threads and they, along with the loctite they will absorb will give the bolt something to hold onto without risk of damage.

unfortunately this means that if you take them out it will take a bit of elbow grease to get the threads clean, but as you have effectively ruined them already this is about the best you can hope for.
flag brucie1
O+
Posted: Aug 7, 2009 at 7:35 Quote
almostwise wrote:
If you've cross-threaded it, you might be able to re-tap it. Locktite will hold the bolts in but if the thread in the hub is knackered they won't hold any torque. Take it to your LBS and ask their advice. If your rotor comes off mid ride, well it wouldn't be fun. You might be able to claim on the warranty.

How would you cross threading your own bolts have anything to do with warranty??
flag k2silencer169
Posted: Aug 7, 2009 at 7:52 Quote
your rotor should have a torque setting written on them. put blue locktie on the bolts and torque them down, but make sure that when you tightening them down that you remember to tighten them in a star pattern, other wise they wont be strait and it will cause the rotor to vibrate witch will make the bolts back off. also rotor bolts just like any other kind of steel boots are torque to yield bolts that means that once they are torqued down once, they will stretch and never be able to be reused properly.
flag almostwise
Mod
Posted: Aug 7, 2009 at 7:53 Quote
brucie1 wrote:
almostwise wrote:
If you've cross-threaded it, you might be able to re-tap it. Locktite will hold the bolts in but if the thread in the hub is knackered they won't hold any torque. Take it to your LBS and ask their advice. If your rotor comes off mid ride, well it wouldn't be fun. You might be able to claim on the warranty.

How would you cross threading your own bolts have anything to do with warranty??
It wouldn't, but if they're 6 months old it's worth trying.
If all else fails you could get them heli-coiled.
flag k2silencer169
Posted: Aug 7, 2009 at 7:58 Quote
idk if any of you guys have much expierence with that kind of stuff, but you cant retap a hub, one the origonal thread pitch was to fine, and two the bolts are way to short to ever get the rite grip on the new thread pitch
flag GenericName
Posted: Aug 7, 2009 at 16:12 Quote
k2silencer169 wrote:
idk if any of you guys have much expierence with that kind of stuff, but you cant retap a hub, one the origonal thread pitch was to fine, and two the bolts are way to short to ever get the rite grip on the new thread pitch

Could you not retap to a slightly larger diameter? Obviously you would need to increase the size of the holes on the rotor as well, by which point you're getting into some pretty ghetto bodging, which I wouldn't really advise.

I stand by my point of using longer bolts if there is some useable thread deeper in the mounts on the hub though.
flag brucie1
O+
Posted: Aug 7, 2009 at 16:58 Quote
GenericName wrote:
k2silencer169 wrote:
idk if any of you guys have much expierence with that kind of stuff, but you cant retap a hub, one the origonal thread pitch was to fine, and two the bolts are way to short to ever get the rite grip on the new thread pitch

Could you not retap to a slightly larger diameter? Obviously you would need to increase the size of the holes on the rotor as well, by which point you're getting into some pretty ghetto bodging, which I wouldn't really advise.

I stand by my point of using longer bolts if there is some useable thread deeper in the mounts on the hub though.

Yeah I would always jury rig my brakes too, that is step one in Darwinism Rolleyes
flag twingate
Posted: Aug 7, 2009 at 17:07 Quote
One option is to rethread the holes to a larger diameter and then insert a helicoil thread. A decent machine shop could help you with this.
Another option (if the hub geometry allows it) would be to drill out the holes and use a bolt with a nut on the back
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