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I've just transferred a pair of rotors from my 26er to my 29er wheels. All went well except for some reason one of the bolts on the rear rotor (the last I was doing) rounded off and I can't get it out. I've got a replacement bolt but how do I get out the other bolt?
Also if I do get it out is it okay just to tighten in the new bolt as all the others are up to torque and were tightened alternately, or do I need to take them all out and start again?
1. If it's a hex head, try a larger size torx bit, might need a tap with a hammer to get it seated.
2. Then try cutting a slot in the head for a flat screwdiver.
3. If that fails cut the head off and get some mole grips on the bit that's left.
You should be fine about the torque settings, just double check after first ride.
As above.... But I would just leave it if you have installed and deal with it later. They are made of cheese so worst case just drill the head off and remove the remaining bolt with mole grips.
There used to be a chap I rode with who only ran 3 bolts to save weight 🙂 and common for these xc weight weeny types. Crazy.
Use a dremel or similar tool with a disc attachment, cut a groove big enough for the heftiest screwdriver you have then apply lots of downwards pressure whilst you use the screwdriver to take the bolt out.
I should imagine you’d be fine replacing it without torquing them all up again.
Edit, beaten to it
Angle grinder and a big flathead screwdriver always works for us
If it's the last one can you wriggle the rotor?
Tried wiggling the rotor but it catches unfortunately. New wheels so I don't want to damage anything!
If all else fails, grind/drill off the bolt head that's damaged.
Then remove the other five bolts and the rotor will come off.
You'll then have a little stub of the failed bolt (the thickness of the rotor). Grab this with a pair of molgrips and twist to remove.
Finally got there hacksawing a rather off centre slot for a screwdriver (had to be a tad careful not to hack the rotor or hub). Hopefully no harm done, except to my nerves.
I'm starting to see the attraction of Centrelock!
Argh! Just had another one go refitting it! Fortunately I managed to back if off. Perhaps I need to consider rotor bolt a 'use once' affair!
The torque settings on the SRAM Centreline rotor says to torque the bolts to 6.2 Nm which seems a tad high considering some Avids I had recommended 2-3Nm, can I torque them a little lower?
Best tip I got from here. Tighten a drill chuck onto the outside of the bolt. Comes out dead easy.
Steve Peat raced for years without all the rotor bolts.
Is your allen key in good condition? If you've damaged 2 now then it's likely worn. Worn allen keys will damage bolts very easily.
Best replacement bolts around are the Hope ones. Nice deep torx heads and good quality bolt. I've actually had a torx bit break before the hope bolt. Lots available from everywhere, only a few pounds, and can be fitted to any rotor or hub.
http://www.chainreactioncycles.com/hope-steel-disc-rotor-bolts/rp-prod9950
I'll probably get some of those Hope bolts as spares for the next time I need to fit a rotor!
You've got it out now, but would these be any use?
[url= https://www.amazon.co.uk/Damaged-E2Buy-Extractor-Stripped-Removers/dp/B073S5G7MC/ref=sr_1_2_sspa?ie=UTF8&qid=1508610588&sr=8-2-spons&keywords=Screw+remover&psc=1 ]https://www.amazon.co.uk/Damaged-E2Buy-Extractor-Stripped-Removers/dp/B073S5G7MC/ref=sr_1_2_sspa?ie=UTF8&qid=1508610588&sr=8-2-spons&keywords=Screw+remover&psc=1[/url]
jam bo - Member
Best tip I got from here. Tighten a drill chuck onto the outside of the bolt. Comes out dead easy.
That's new to me, will try that if ever necessary!
Yeah, could have done with that too a few months ago. Tried everything, large torx bit, cutting a slot in it, scree extractor. In the end did as above and drilled the head off, removed the rotor then used a pair of molgrip to remove the sticky out bit. Was pretty easy after I wasted two evenings on all the other methods!
Something to consider for future use are the Wera Hex Plus and Torx L-keys. Very well machined, especially the hex keys which have some patented geometry to allow either more force to be applied with much less chance of rounding the head of fasteners.
They aren't cheap but they're great value I think.
I'm starting to see the attraction of Centrelock!
I am a massive fan of the centrelock! 🙂
Chase the nasty blue thread lock off the new bolts before you use them. Use a tiny dab of copper slip, and the correct torque.
Glad your sorted, your heart sinks, well mine did. I had 3 ,very embarrassing.
I went down the easy out route. Drilled a hole down the middle, and used the easy out and they all undid fine.
Might help some one in the future.
The threadlock is pretty tacky and to be fair I think that the bolts have been used 3 or so times before (and have had a rough time out in all weathers); I was probably asking for trouble.
I think that from now on it'll be new bolts each time.
rotor bolts can be reused plenty of times with no issues. I’d be looking at the quality of your tools first.
Allen keys like screwdrivers do need replacing. Throw the old ones out as well. The Wera stuff is lovely
Might not have worked with your situation but a good tip I picked up when working with rounded or damaged hex or torq bolts is an elastic band or piece of inner tube stretched over the end of your tool
Scotscrote » Grab this with a pair of molgrips
There's two of the buggers...?!
Saints preserve us.
elastic band or piece of inner tube stretched over the end of your tool
😯
Kinky
It might not be tool......it might be the bolt.....or the size choice?
I think they usually T25....but a T20 will work just about.....perhaps some errors occur when T20's are used accidentally!! 😉
Be careful with using grease on the threads- approx 90% of bolt torque is lost in friction, so reducing it with grease can lead to proportionally large increases in total torque: you can bugger something up badly.