10 year old self extracting cranks won't budge

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10 year old self extracting cranks won't budge
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flag Occl
Posted: Apr 18, 2023 at 10:46 Quote
2013 Specialized S-Works Stumpjumper with carbon cranks, non-drive side has no bolt, drive side appears to be self extracting. I removed the dust cap, reached in to the other side with a 6mm t-handle and can get the wrench in but I can't budge the bolt. I tried adding a breaker bar to my t-handle and it felt like the wrench was going to break before the bolt would let go.
I've read that these are torqued to some crazy number when built and I'm thinking this one has probably never been apart (I bought the bike used).
Any suggestions? I don't mind taking it in to my LBS if needed, especially if that means not breaking something, stripping the head of the bolt and costing more $ as a result.
Thanks for any help.

This is not mine but it's the same type of crank (for reference):
http://twentynineinches.com/wp-content/uploads/2012/08/DSC01149.jpg
flag eshew
Posted: Apr 18, 2023 at 18:29 Quote
Pb blaster or another "creeping" lube and let it soak. Reapply and let it soak again... For a few days.
flag M0rd4c4i
Posted: Apr 19, 2023 at 3:46 Quote
A bit of percussive mechanics may help some too, as physical shock may help oil penetrate and also slowly break the binding.

Do not hit it with the biggest hammer you can find with all your might though, your probably best using a plastic mallet and giving it reasonable force.
flag adnauseam
O+
Posted: Apr 19, 2023 at 7:55 Quote
I highly recommend "Freeze Off" - Available at most Napa Auto Parts locations.

It makes the metal extremely cold and shrinks the pieces just enough to crack rust and other seals. You need to spray alot of it for it to stay cold and penetrate properly. Shit's toxic so do it outside.

Anyways, a can is worth the $10 or whatever it is. You can use it for several applications, and I've had great success with it as a shop mechanic. It's also carbon friendly.
flag Occl
Posted: Apr 21, 2023 at 5:39 Quote
Thanks for the help. I've ordered the special tool to remove it and began soaking with PB Blaster. I'll post back with the results.
flag Occl
Posted: Apr 24, 2023 at 16:20 Quote
Well, I soaked the crank bolt with PB Blaster, tried the new tool from Specialized (6mm Allen, specially designed for this) and no luck. The tool just spun in the bolt. I guess I'm stuck with the small ring staying on the cranks. I can't see how this thing would come off if the Allen key can't get a good bite in there.
flag eshew
Posted: Apr 25, 2023 at 13:45 Quote
If the tool spun in the bolt, is there a chance the bolt is 8mm?
flag Occl
Posted: Apr 25, 2023 at 17:37 Quote
eshew wrote:
If the tool spun in the bolt, is there a chance the bolt is 8mm?

No, the hole to put the Allen wrench in is too small for an 8mm.
flag M0rd4c4i
Posted: May 3, 2023 at 13:56 Quote
JonnyTheWeasel wrote:
Photo?

Photos are definitely needed now, as we can only guess what's going on otherwise.
flag anoplura
Posted: May 3, 2023 at 18:58 Quote
I remember dealing with a very similar situation a few years ago. Specialized carbon cranks (can't remember the bike) and the bolt was galvanically stuck in the axle. We used a penetrating anti-seize oil of some kind (brand escapes me) and had to get a specialized (small s) tool to remove the bolt.

If I remember correctly though, it was a long Torx driver for our 1/2" breaker bar, not an M6 Allen. A quick Google search seems to confirm this, as at least some Specialized carbon cranks used a T45 Torx head.

Hopefully this is why it is spinning in the socket, and it's not actually stripped?
flag bewheels
Posted: May 5, 2023 at 4:59 Quote
First thing would be to double check whether it is a Torx head as suggested by @Anoplura. To state the obvious...regardless of the different methods of removal, there needs to be a proper and snug fit between the tool and the bolt.

I don't recall the specifics about this crank and it is a bit hard to tell from the photo link you supplied - how is the self-extracting configuration set-up?
Does the extraction bolt engage with the outer cap or is there more to it?

The reason I ask is that it can make things easier if you can separate the "extraction" from getting the parts moving.
In other words, if the outer cap is what the bolt pushes against to create the "self extracting" mechanism, remove the cap and just work on getting the bolt free*. Once the bolt is free, grease everything up and reassemble without torquing down the bolt and then extract the crank.

Removing the bolt - There are generally two issues when trying to remove this bolt:
1. Ensuring the cranks are not moving every time pressure is put on the bolt because that motion is absorbing torque that needs to be going into the removal of the bolt. Placing a block of wood under the crank arm to keep it from moving at all can be a huge help.
2. Getting enough sudden torque applied to the bolt. Cheater bars, breaker bars, etc do a great job of providing leverage and work the majority of time. An alternative is to use an impact driver which delivers high torque very quickly. The hammer versions (https://m.media-amazon.com/images/I/71AqdV-TPIS._AC_SL1500_.jpg) are much cheaper and don't require compressors and all that. The down side to using pneumatic impact drivers (besides cost and needed set-up) is that if there is a sloppy fit between the bolt and the tool it will destroy the bolt very quickly. A hammer impact driver only moves a bolt a little bit on each whack of the hammer. The downside of a hammer impact driver is if a bolt is really stuck, the driver will just spin in your hand.

Of course all of the above is in addition to the various penetrating chemicals mentioned by others.

*This may be what you are trying to do. If so, just ignore that suggestion.
flag dood
Posted: May 5, 2023 at 5:31 Quote
M0rd4c4i wrote:
A bit of percussive mechanics may help some too, as physical shock may help oil penetrate and also slowly break the binding.

Soak with ATF/diesel/kerosene.

Have you tried hitting it with your purse, or was the 12-lb sledge not in reach?

10 years ago, everyone would have raved about how strong the carbon is........It'll be fine. Either you get it off by waiting for solutions and fluids to undo 10 years of metals lovingly making babies with each other, or, 2 seconds of hate-f-cking them on the end of a wooden block. HIT the bloody thing and get back to your life.

If you've already tried a breaker on things, you're outside of anything resembling 'normal' torque for the size of fastener (especially in the 1/2 to 5/8" range.....)being used. It's seized, and needs a little 'howdy' to unf--k the inclined plane.

Hitting, is why mechanics have impacts in the first place - only they can do it faster. Lay into it.
flag muddytreker
Posted: May 5, 2023 at 6:12 Quote
Grrrrrrrrrrrrr! yeh give it some and shows us the carnage

https://www.youtube.com/watch?v=7ZxApjtEWFc
: )
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