Sram crankset and GPX BB advise

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sore thumb
Posts: 223
Joined: 7 Jan 2007, 10:27am

Sram crankset and GPX BB advise

Postby sore thumb » 12 Dec 2014, 4:32pm

I've got myself a new singlespeed sram crank set

This one

http://www.bike24.com/1.php?content=8;s ... duct=29035


I build all my own bikes and have fitted cranksets before.


The question I would like to ask is, do you put loctite on the crankbolt?

I normally put loctite on the crankbolt, but for some reason this part was covered in grease already in the box.

I have looked at the instructions and it identifies all the obvious parts that require grease and these are pre greased correctly. The instructions do not state if the crankbolt needs greasing, only shows the required tourque.

I though it was safer to have no grease but to loctite the crankbolt.

Any help would be gratefully recieved.

Thanks

Valbrona
Posts: 2430
Joined: 7 Feb 2011, 4:49pm

Re: Sram crankset and GPX BB advise

Postby Valbrona » 12 Dec 2014, 6:01pm

I routinely apply a small amount of grease to a crank bolt. I have available anti-seize assembly grease, but bearing grease would be okay. If a crank bolt comes with some pre-applied Loctite that says nothing about correct assembly procedure but instead says more about a manufacturer not wanting a warranty claim.
I should coco.

Brucey
Posts: 43049
Joined: 4 Jan 2012, 6:25pm

Re: Sram crankset and GPX BB advise

Postby Brucey » 12 Dec 2014, 7:00pm

these instructions;

https://sram-cdn-pull-zone-gsdesign.netdna-ssl.com/cdn/farfuture/FmnsINy3tPU8poCYzhHTpxpScqyrHnsRtDhp1BiiTOs/mtime:1372788144/sites/default/files/techdocs/RED%20Crank%20BB%20PRINT.pdf

clearly indicate to grease the crankbolt thread.

I'd be tempted to use a little soft Loctite on it myself, because these bolts do occasionally back out. This won't affect the torque setting, because most Loctite grades are designed to lubricate (when uncured) in the same way as oil or grease does.

I wouldn't use a full strength product though; the breakaway torque might become excessive if you treat the full area available.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

tim-b
Posts: 1675
Joined: 10 Oct 2009, 8:20am

Re: Sram crankset and GPX BB advise

Postby tim-b » 13 Dec 2014, 6:00am

Hi

I've a Truvativ Elita (made by SRAM) with the same BB. Assemble it as SRAM recommend, I haven't had any problems with mine loosening in 10000 miles

You can always carry an 8mm allen key for the first few rides if you're not sure. That bolt is also there for removing the cranks, you'll rue the day that it won't shift!

Regards
tim-b
~~~~¯\(ツ)/¯~~~~

sore thumb
Posts: 223
Joined: 7 Jan 2007, 10:27am

Re: Sram crankset and GPX BB advise

Postby sore thumb » 14 Dec 2014, 2:05pm

Many thanks, I have installed the crankset using grease, we will see what happens?

Thanks