Shock bolt stuck and rounded

[Keisari66]

So, bought a new shock and tried to uninstall my DPX2. Haven’t taken it off since I bought the bike and it’s apparently pretty stuck.

I tried first with the correct size hex but eventually with enough force it just spinned around and rounded the bolt head. Then I hammered a Torx in there and tried with a 50cm lever and still it didn’t budge and eventually the Torx spinned around too. I’m out of options, the bolt seems like a hollow aluminum bolt so “easy out” probably won’t work either. I suppose there’s been a pretty liberal loctite application from the factory...

Suggestions?

 

[davidjmilli]

Hi. Looks like a job for a screw extractor. The work by screwing in counter clockwise so when you wrench into them to tighten they unthread the other screw. Local hardware store will stock them or a quick google will show you the way.
Amazon have loads. Only thing to watch is some can be of dubious quality so it’s a bit of a lottery a more expensive one may not always be the best bet as it could have come out the same factory as a $4 set.


This one has an image of how they work.

 

[Andy.M]

Or find a local small engineering company and ask them if they can help.

 

[Cisco]

Or find a local small engineering company and ask them if they can help.

Yes.

As you have it off the bike a small fabrication yard can tack weld a nut onto the bolt head and it will come out easily.

 

[steve_sordy]

According to your photos, you have access to the other end of the bolt, so there is no need for bolt extractors or anything very technical. Drill out the bolt from the other side. Use a centre punch to make a small dimple in the centre (to stop the drill point from wandering at start up). Then start with a small drill, say 3mm or so. The friction will generate heat and loosen the grip of any Loctite that is in there. The drill torque will act to unwind the bolt. If the 3mm drill doesn't work, use a bigger one. Nice and steady!

Don't take it too far, as soon as the mangled bolt head is far enough out to grab with pliers remove it that way.

 

[blueglide]

I have used a Dremel to cut a groove in the head of a bolt damaged like that and then used a large blade screwdriver to remove the bolt after liberal use of 'Liquid Wrench' and possibly some heat around the hole in the linkage to breakdown any locktite and expand the hole slightly. You might be able to get an EZ Out to work also.

 

[Keisari66]

According to your photos, you have access to the other end of the bolt, so there is no need for bolt extractors or anything very technical. Drill out the bolt from the other side. Use a centre punch to make a small dimple in the centre (to stop the drill point from wandering at start up). Then start with a small drill, say 3mm or so. The friction will generate heat and loosen the grip of any Loctite that is in there. The drill torque will act to unwind the bolt. If the 3mm drill doesn't work, use a bigger one. Nice and steady!

Don't take it too far, as soon as the mangled bolt head is far enough out to grab with pliers remove it that way.

I think this is a hollow bolt, not sure if there’s any material to drill to inside the threaded part ?

I stuck an allen key with epoxy into the bolt head and will try if it works in a few hours...

 

[steve_sordy]

@Keisari66 What makes you think it's a hollow bolt? It's a high stress bolt and it's alloy!
Even if it was hollow, a larger diameter drill would still find something to grab hold of.

Good luck with the epoxy route.

 

[Landy Andy]

Drill into the otherside then hammer in a torx bit, do this along with the Allen key trick you are trying, or drill and torx bit this side too. Then attempt undo with applying pressure on both sides of the bolt.

 

[Keisari66]

@Keisari66 What makes you think it's a hollow bolt? It's a high stress bolt and it's alloy!
Even if it was hollow, a larger diameter drill would still find something to grab hold of.

Good luck with the epoxy route.

I’ll try the drilling if this fails ?

 

[Keisari66]

Epoxy failed, drilling failed. Or well, it helped when I drilled deep enough for the 10mm bolt extractor to have enough grip. Tried with a smaller extractor first but almost went through the bolt and it didn’t come off.

All in all reason was lots of loctite under the bolt lip and bolt shaft.

 

[Zimmerframe]

Congratulations !!!

Wow, you have a huge palm

 

[steve_sordy]

Epoxy failed, drilling failed. Or well, it helped when I drilled deep enough for the 10mm bolt extractor to have enough grip. Tried with a smaller extractor first but almost went through the bolt and it didn’t come off.

All in all reason was lots of loctite under the bolt lip and bolt shaft.

View attachment 55301

View attachment 55302

View attachment 55303

I said to drill from the other end! The torque unwinds the bolt.

Anyway, you got it out without damaging the bike.

 

[16vdady]

I said to drill from the other end! The torque unwinds the bolt.

Anyway, you got it out without damaging the bike.

 

[Zimmerframe]

I said to drill from the other end! The torque unwinds the bolt.

Unless you use a left handed drill bit. Then you can do it from that end.

 

[16vdady]

Great work! Strangely satisfying when you get it out.

 

[Keisari66]

I said to drill from the other end! The torque unwinds the bolt.

Anyway, you got it out without damaging the bike.

I drilled from the other end too with no help? just no photo of it! It was so tight my drill wouldn’t have had the initial power needed to unwind it. I had a 40cm lever on that extractor and I was jumping on it with my full 200lbs.

 

[steve_sordy]

Unless you use a left handed drill bit. Then you can do it from that end.

Sometimes I cannot tell with certainty whether you are joking or not, but I hope you are now.

 

[Zimmerframe]

Sometimes I cannot tell with certainty whether you are joking or not, but I hope you are now.

I know, it's tricky isn't it !!

This time , serious ! If you use a left handed drill bit with the drill in reverse, then quite often as the drill bites it will unwind the stuck bolt.

 

[steve_sordy]

I know, it's tricky isn't it !!

This time , serious ! If you use a left handed drill bit with the drill in reverse, then quite often as the drill bites it will unwind the stuck bolt.

Ah, you have a reverse option!! High Tech Stuff. I would have to ring up the National Grid and get them to reverse polarity for the whole of my village. On balance it is quicker to drill from the other end (and not have to buy a left hand drill either.)

 

[Zimmerframe]

On balance it is quicker to drill from the other end (and not have to buy a left hand drill either.)

Sometimes that's not an option !! Hence why the left hand drill bit cheapo set from china can be invaluable for those rare moments you need it ! It might be that Australian ones are that way round as standard ? Are drill bits formed by liquid metal being poured down a sink ?

 

[GoJoe]

Drill into the otherside then hammer in a torx bit, do this along with the Allen key trick you are trying, or drill and torx bit this side too. Then attempt undo with applying pressure on both sides of the bolt.

Landi Andy, thanks for your post, it got me out of a jam!

 

[Landy Andy]

Landi Andy, thanks for your post, it got me out of a jam!

View attachment 92770

Glad to help.

 

[RustyIron]

Drill out the bolt from the other side.

Yeah, I know this thread has been going on longer than I've been here. But sometimes when an answer to a question is several orders of magnitude better than all the others, you have to abandon protocol and bump it back up to the top.

The beauty of Steve's solution is its elegant simplicity. Often, the reluctant fastener will just spin out when you drill it. If it's still stuck, use the next size drill. On really stubborn problems, you'll drill through the screw, and you'll start seeing the female threads. At this point, get out your picks and start digging the remnants of the screw by hand. Because you don't want to increase the hole size by any appreciable amount, you want to want to center punch the screw exactly in the middle. It's also important to be able to drill a hole perfectly straight. Practice precision skills on inconsequential projects, and then you'll have them when it really matters.

The left hand drill bits would not be "wrong" for this application, but it would be more difficult to start the hole dead center in the buggered up screw head. It's easier to find center from the other side. Also, I'm a cheapskate. I only have a few compete sets of left hand drill bits. They're expensive. I have many more right hand drill sets, and they're cheaper, so I'd rather use those first. Save the expensive tools for when you REALLY need them.

 

[steve_sordy]

Gosh @RustyIron that made me simultaneously pleased and blushing with embarrassment.

I read out your 2nd and 3rd sentences to my wife, so pleased was I by your post. Thanks.

Are you sensing that I don't get much praise in my everyday life?
I must try harder.

 

[RustyIron]

I read out your 2nd and 3rd sentences to my wife, so pleased was I by your post. Thanks.

No worries, mate. We men need to stick together.

Someday, and that day may never come, I may call upon you to write something nice about me, in an attempt to convince my wife that I’m not really all that bad.