With a combination of a crap allen key and being in a rush, I have managed to round off a small bolt on the derailleur hanger, its knackered!

Is it just best to take it the LBS, or is there anything I can try?

If you can clamp it sufficiently you could try knocking in a slightly larger torx bit or a spline bit. It has worked for me in the past with rounded allen bolts

Could you grind a line in the bolt head (say with a dremel or similar) and use a screwdriver to loosen it off?

(Cant see the photo)

Can you post your image so we can see it? I use this site then use quick link for forums

https://postimages.org/

Dremel a groove. Works for me!

I’d hammer in a torx or flat head screw driver.

I had an issue years ago with a Kona dope dropout, the combination of shallow allen key hole in poor quality black bolt drowned in factory threadlock made it a nightmare, had to resort to drilling through the bolt with cobalt bits increasing in size then used a pick to remove the remaining metal and re tapped to clean up.

Araldite an old Allen key in?

I’d hammer in a torx

This^^

Refit rear wheel and axle for support, lay bike on its side with an additional solid support directly under the axle, squarley tap in a slightly larger torx bit, put some good weight/pressure on it as you turn (remember – lefty loosey😉😉). Might also be worth pouring some boiling water on it just before you try to unscrew, which might soften any threadless

Cheers for all the advice.

In the end I managed to remove the bolt by using a small screwdriver and a thick elastic band, it worked!

Next question, I am going to replace my multitool as I can see that the hex wrench I have been using is damaged and almost rounded off.

I already have a separate chain tool, so what high quality hex wrench multitool would you guys recommend?

Next question, I am going to replace my multitool as I can see that the hex wrench I have been using is damaged and almost rounded off.

Multitools aren’t really intended for doing proper maintenance, they’re for emergencies out on the trail. For doing regular maintenance, you are much better to buy proper tools. You will have far fewer problems.

I have ordered separate Park Tool hex tools (not multitool) for my tool box at home.

I would have gone with a set of Wera hex plus, if you shop around can be found for just over £20 and should last a lifetime. Never failed us yet

https://www.manomano.co.uk/p/hex-plus-key-set-ball-end-metric-multi-sleeve-set-of-9-15-10mm-4256396

Have a set of these at bottom of toolbox….been there a couple of decades…very effective voodoo doll…

Random Amazon link available all tool stores / motor factors

It may be possible to cut the end of the Allen key off to get a new sharp end.

I’ve never found easy outs to be anything other than a complete pain. I think I’ve yet to extract a bolt with one – they usually snap in the hole and are then a right pita to remove due to them being hardened steel and v difficult to drill.

https://www.halfords.com/tools/hand-tools/all-hand-tools/laser-damaged-hex-bolt-extractor-set-7pc-208622.html?istCompanyId=b8708c57-7a02-4cf6-b2c0-dc36b54a327e&istFeedId=367c5610-f937-4c81-8609-f84582324cd6&istItemId=ittamtrtm&istBid=t&_$ja=tsid:94971%7Ccid:865695754%7Cagid:42483195983%7Ctid:aud-518244443164:pla-331014971495%7Ccrid:203186066553%7Cnw:g%7Crnd:8261748524346444657%7Cdvc:m%7Cadp:%7Cmt:%7Cloc:1006815&gclid=Cj0KCQjwsuP5BRCoARIsAPtX_wGAixdpzpGk-8acuZRymvbQ7PQw6tu4gQ8qNyJmxcDQLEGhzfSuz5gaAjqJEALw_wcB

I have got a set of these but I’ve yet to try them in anger…

This.
Or tap a Torx in to see it that bites. And then replace the bolt

Subscriber
I’ve never found easy outs to be anything other than a complete pain. I think I’ve yet to extract a bolt with one – they usually snap in the hole

I presume these were always situations were some one else had rounded out the bolt head otherwise that looks like self incrimination🤔

Heads up! Bullguard is telling me there is an infected file on this page. Apparently http://www.paulpollard.co.uk/bike.jpg contains a trojan you all might want to scan your devices.

@antigee 😂 quite happy to admit after 35 years of messing with motorbikes, Land rovers and mtb’s I’ve round plenty of bolts in my time – less so these days as use a torque wrench when needed and with experience I think you get a better sense of when the limit is approaching..

I have a mate who absolutely insists on putting a ‘farmers nip’ on every bolt – cue every thread being stripped or impossible to undo! 😂

cheers timbog160 taken as intended and farmers nip isn’t an expression I’ve heard for many years 👍

I’ve never found easy outs to be anything other than a complete pain

On the very rare occasion that they work, they’re great.

timbog160
Subscriber

I’ve never found easy outs to be anything other than a complete pain. I think I’ve yet to extract a bolt with one –

Depends a lot on the situation tbh. They’re good for removing a damaged but not stuck bolt, but they’re a long shot for removing a stuck and subsequently damaged bolt (since if it’s so stuck that the proper tool rounded off the bolt, it’s probably also too stuck for the alternative tool to work) But if the bolt got rounded through using a bad tool, or a bit of carelessness, then it’s way more likely to work

^ agree. If you’re careful to use tools in good shape, or are at least sufficiently aware of the state of the tools you’re using, if its gone this badly wrong an easyout is unlikely to help. IME a tool of some kind smashed in there, leaned on very heavily, and rotated through some other means while you maintain pressure on it is much more likely to be successful. Otherwise it’s drill and tap. Our kit uses a lot of stainless fixings in to aluminium. 🙂
Well done on getting that out OP. The thing is probably supposed to only be done up half tight (or should be) by the looks of it and you could have had real problems with that. 👍

Aldi are selling the tool you need right now.
Aldi tool