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GXP crank arm stuck. HELP!

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dboneslick

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Discussion starter · #1 ·
Hi,

I am trying to remove a set of Sram X0 cranks and the non drive side crank arm won't budge. I loosened the 8mm bolt and it got very tight. The crank still wouldn't budge. I kept turning and the bolt came out. The crank arm is still there.
I even tried tapping the crank arm with a rubber mallet with no results. The GXP crank arm is supposed to come off without a removal tool. The bolt and the retaining circle both came off and left the crank arm in place.

Any suggestions?
 
#2 ·
there is supposed to be 2 bolts... the 8mm inner bolt and a thinner almost washer like one that is like a 22mm.. the outer one is there for just removing and it uses the inner 8mm bolt to actually push the crank arm off sounds like you/they/ who ever installed the cranks never put the outer bolt in. or is that what you are calling the "retaining circle?" if it is, install everything again... make sure you torque the outer(retaining circle) properly to spec and make sure the washer is between the 2 bolts.. this will keep the outer bolt from turning with the inner one.

you can get the whole set for like $20 depending on which model crank you have...
quick google search..
GXP crank arm bolts - Google Search
 
Discussion starter · #3 ·
The outer bolt was on! When I tried to remove the inner bolt, the crank arm was on so tight that the outer bolt stripped out. Now the inner and outer bolts are off and the crank arm is still in place. It is frozen to the spindle.
Yes, the splines were greased before assembly.
 
#4 ·
dboneslick said:
The outer bolt was on! When I tried to remove the inner bolt, the crank arm was on so tight that the outer bolt stripped out. Now the inner and outer bolts are off and the crank arm is still in place. It is frozen to the spindle.
Yes, the splines were greased before assembly.
Click to expand...
next time/reinstall use anti seize over grease it'll avoid this issue in the future..

but for now... when you say stripped out did it actually rip the threads? or did it just spin out with the inner bolt?

pictures help :\
 
Discussion starter · #5 ·
The outer bolt isn't stripped. It just backed out. I was really torquing down on the inner bolt and the crank wouldn't budge. Finally, the outer bolt just started spinning with it. I will try to post some pics.
Basically, that crank arm is frozen on there and won't budge. Not even with a rubber mallet.
I can't heat it because the crank arm is carbon fiber.
 
#6 ·
there should be a washer in between the 2 bolts to prevent that

try cleaning everything good and re-installing them both with the washer between and grease the crap out of it... .. torque the outer one in good.. if you have some loctitie or teflon tape use it on the outer bolt.... should work...

might want to soak the crank/spindle with some penetrating oil for a bit first... (clean if off the threads for the outer before installing if you do)
 
Discussion starter · #7 ·
thomllama said:
there should be a washer in between the 2 bolts to prevent that

try cleaning everything good and re-installing them both with the washer between and grease the crap out of it... .. torque the outer one in good.. if you have some loctitie or teflon tape use it on the outer bolt.... should work...

might want to soak the crank/spindle with some penetrating oil for a bit first... (clean if off the threads for the outer before installing if you do)
Click to expand...
Ok. I'll have to get a bigger wrench. How hard can I torque on the inner bolt before I risk damaging the threads?
When The outer bolt came off, I was really giving it everything I had. The outer bolt finally started spinning and the arm didn't budge. Even if I get the outer bolt on extremely tight, I am worried about damaging the threads on the spindle from the torque I will have to apply.
 
#8 ·
the spindle is stronger than the bolt usually..... the bolts are alum,, the spindle is steel.. you'll blow the bolt first. honestly if it gets that bad then you're screwed and it wont matter as you'll be cutting them off ...:madman:

if you have air tools?.. the nut end of the nipple is the right size (it's what I actually use)

just be careful and use a deepwell socket. But if using a open end push with your free hand's thumb press in to make sure it doesn't strip out and damage the bolt.. (thou is it's all that bad for the 20 bucks I recommend replacing the bolts anyway)

I have had to once tap the arm with a rubber hammer... get the tension between the 2 bolts as high as you dare then lightly tap the crank arm.. do another 1/4 turn on the bolt and tap some more... also tap down on the knuckle as well as tap out.. anything to vibrate it free
 
Discussion starter · #10 ·
thomllama to the rescue! The air hose fitting worked and the crank arm is off! I love you man in a guy sort of way.

Ok, One more question:

The crankset is a bit loose when torqued down. There is a hair of lateral play. This is why they were stuck in the first place. I overtorqued them trying to eliminate the play. I have a 73mm shell and I'm using no spacers. It is a threaded GXP bb with X0 cranks. Should I use spacer on the non drive side?

On edit: If I could re-rep you, I would!
 
#11 ·
Gxp cranks just trap the non drive side bearing's inner race.. the spacers have no effect on side to side play like Shimmy or Race face...

(so you get an idea of what i'm talking about) Trail Tire TV: Sram's GXP Bottom Bracket, how it differs from others

if there is side play then either the crank arm isn't seating against the bearing race (dirt, crud in the splines of the arm or n the spindle) or the non drive bearing is worm out.

best way to check is remove the non drive bearing/cup and try hand fitting it all together off the bike.. see if the bearing/cup moves on the cranks and you can much easier see what the issue is and where...

I absolutly love the GXP BB system.. it is by FAR the best design of all cranksets out there.. but,... there is an issue thou.. SRAM/truvativ usues the most crappy bearings ever...:madmax: if you can afford it, get after market bearings.. (Enduro bearing and seals ceramic kit being my first choice)

dboneslick said:
thomllama to the rescue! The air hose fitting worked and the crank arm is off! I love you man in a guy sort of way.

Ok, One more question:

The crankset is a bit loose when torqued down. There is a hair of lateral play. This is why they were stuck in the first place. I overtorqued them trying to eliminate the play. I have a 73mm shell and I'm using no spacers. It is a threaded GXP bb with X0 cranks. Should I use spacer on the non drive side?

On edit: If I could re-rep you, I would!
Click to expand...
depending on what yr they are tho it may need a spacer on the drive side just to set the support on the spindle correct... the newer moels SRAM/Truvativ designed them to be able to handle current BB cup mounted extras like chain guides of BB mounted derailleurs so even a 73mm BB MAY need a spacer behind the drive side cup (I believe anything after 2010 the extended that setup.. but not positive on that date)
 
#12 ·
use never seize on assembly on the spline over grease.. as well as the 8mm bolt threads (or use teflon tape on the bolt if you can.. I like it better as it's cleans off better down the road and kinda locks the threads over grease/anti seize).. it'll make life down the road much better ;)
 
Discussion starter · #13 ·
thomllama said:
Gxp cranks just trap the non drive side bearing's inner race.. the spacers have no effect on side to side play like Shimmy or Race face...

(so you get an idea of what i'm talking about) Trail Tire TV: Sram's GXP Bottom Bracket, how it differs from others

if there is side play then either the crank arm isn't seating against the bearing race (dirt, crud in the splines of the arm or n the spindle) or the non drive bearing is worm out.

best way to check is remove the non drive bearing/cup and try hand fitting it all together off the bike.. see if the bearing/cup moves on the cranks and you can much easier see what the issue is and where...

I absolutly love the GXP BB system.. it is by FAR the best design of all cranksets out there.. but,... there is an issue thou.. SRAM/truvativ usues the most crappy bearings ever...:madmax: if you can afford it, get after market bearings.. (Enduro bearing and seals ceramic kit being my first choice)

depending on what yr they are tho it may need a spacer on the drive side just to set the support on the spindle correct... the newer moels SRAM/Truvativ designed them to be able to handle current BB cup mounted extras like chain guides of BB mounted derailleurs so even a 73mm BB MAY need a spacer behind the drive side cup (I believe anything after 2010 the extended that setup.. but not positive on that date)
Click to expand...
Thanks for the advice. Something might be wrong with my setup. The cranks and BB are both new. I installed it with no spacers and no washers. The diagram with the BB seems to show that you only use the wavy washer with a press fit GXP, not the threaded. I put the wavy washer on the drive side and it didn't help. The crank just won't get tight enough. I decided to try the wavy washer on the non drive side and it works like a charm. I basically just need 1mm more thickness between the crank arm and the BB on the non drive side. Without the extra washer, I can tighten the crank all the way down but it will never contact the bearing cover and make the assembly tight. It's almost like I have a 72mm shell instead of a 73mm shell.
 
Discussion starter · #14 ·
Here is a picture

This is the non drive side. It's hard to tell, but there is a very thin washer between the crank arm and the bearing cover. If That washer is removed, the crank arm will never contact the bearing cover no matter how much I tighten the nut. This results in a tiny bit of lateral play.
The diagram with the BB hints that I shouldn't use any washers or spacers with my 73mm shell. It works great with that thin washer in there. Will this hurt anything?
 
#16 ·
I had the same problem with a used Cannondale F-29 I just purchased. The bolt came out but the crank arm wouldn't budge. Lucky for me, I had a "jaw puller" in my tool box and it worked great. I kept the 8mm bolt slightly thread and put a piece of metal over it for the jaw to push on as it popped the crank loose.
 
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