SRAM crank extraction woes, lockring comes out

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n808
Posts: 103
Joined: Sun Mar 16, 2014 3:09 pm
Location: Seattle, WA | Gjøvik, Norway

by n808

I wanted to remove my freshly installed SRAM Red GXP crank to add some grease to the splines to ease future removal, but the "self-extracting process" does not work. I ended up just backing the 16mm lockring out, even though it was securely loc-tited in place. I tried to clean it thoroughly, add green loctite, re-tigthen it using the hex head on a 7/16 inch bolt as 16mm hex tools are not readily available. Green loctite seemed to be the color that had been there before, but I am not sure that's the best variant to use. Still, after waiting 24 hours to let it cure, I ended up backing out the lockring again. Next I will have to try red ("permanent") loc-tite :S

Has anyone else run into this problem? I'd hate to give up, just postponing the problem until I really need to remove the crank-arm for maintenance or replacement.

Edit: I re-installed the lockring with red loctite. Then I found a thread in another forum claiming there should be a washer between the lockring and the 8mm allen bolt used to extract the crank-arm. There was no such washer in mine. So before the red loctite set I decided to pull them apart again to see if I could find the right kind of washer. This time the crank-arm finally decided to budge instead of the lockring, and that was even before the permanent loctite had cured. Upon re-reading the technical manual, there is indeed no such washer. I guess I'll just re-install, but use blue loctite. Hopefully, with more grease, and the repeated installation and removal, the crank-arm will get somewhat easier to remove next time.
(2012/2014) Scott Addict R1, SRAM Red 6.6kg | 2012 Scott Scale Pro, SRAM X0, 9.4kg

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yourdaguy
Posts: 2204
Joined: Thu Mar 17, 2005 3:25 am
Location: Southern Indiana USA
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by yourdaguy

I have many SRAM cranks and I have never seen this problem. I have never used loctite on them either. I would start with buying the proper hex tool. I have probably taken them off over 300 times between them since I "fiddle" a lot. Most of them are MTB but I have road too although older road than yours. I don't really see how this can happen since the loosening of the bolt should not pull that strongly on the locking ring.
For certain parts stiffer is more important than lighter.

n808
Posts: 103
Joined: Sun Mar 16, 2014 3:09 pm
Location: Seattle, WA | Gjøvik, Norway

by n808

Thanks for your reply. Under normal circumstances the lockring requiring a 16mm hex tool does not come loose. It comes loctite'd in place from SRAM. But in my case the force required to pull off the new and tight fitting crank-arm was so high, that the inner bolt's pressure on the lockring caused it to catch on and drag it out along with it, while the inner bolt normally just rotates inside it, while pushing it out.
I think when I got it to come off before he red loctite had cured, I had added more grease between the lockring and the inner extraction bolt, which made it not catch onto the lockring and drag it with it.
The hex bolt head + wrench worked great for its purpose - to get the lockring back in place. No need to mail order and wait for an expensive 16mm hex key when the 65c bolt worked fine. I probably will never need it again, now that I know the procedure for very tight crank-arms (add grease between lockring and inner bolt)
The X0 crank-arm on my Scott Scale comes off without nearly as much force as the new Red crank-arm needed. And yes, an equal amount of force was required to install it, and with plenty of grease. Just very tight tolerances, which is good I guess.
(2012/2014) Scott Addict R1, SRAM Red 6.6kg | 2012 Scott Scale Pro, SRAM X0, 9.4kg

goodboyr
Posts: 1497
Joined: Wed Jan 10, 2007 10:56 pm
Location: Canada

by goodboyr

I believe the diagram in the SRAM manual shows where you are supposed to add grease.

Causidicus
Posts: 320
Joined: Tue Apr 17, 2012 11:20 am

by Causidicus

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Last edited by Causidicus on Wed Jun 18, 2014 1:23 am, edited 1 time in total.

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Andrew69
Posts: 593
Joined: Thu Feb 19, 2009 10:52 am
Location: ɹǝpunuʍop

by Andrew69

I had the same problem, even with a 16mm hex key.

After many attempts and a LOT of swearing, I ended up giving the crank arm a couple of taps with a rubber mallet and then it released fine.
Having said that, I did have to torque it to the max value to get it to seat properly in the first place (even with plenty of grease)

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