Stuck crankset removal (XTR-970 crank)
#1
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Thread Starter
Stuck crankset removal (XTR-970 crank)
I'm trying to remove an older XTR crankset, which is basically the odd duck as far as Shimano cranks. It's Hollowtech, but has a self-extracting system.
Here's the relevant video (I have the correct tool).
The problem I'm having is that the crank is thoroughly stuck. I can loosen the inner bolt, but then it jams against the outer FC-35 and just gets stuck, rather than pulling the crank arm off. The self-extractor obviously doesn't have enough to handle a 6 year crank that's never been taken apart. For reference, I've tried both a 18" breaker bar and cordless impact driver.
Any suggestions for how to loosen the crank? Hammer? Heat?
Here's the relevant video (I have the correct tool).
The problem I'm having is that the crank is thoroughly stuck. I can loosen the inner bolt, but then it jams against the outer FC-35 and just gets stuck, rather than pulling the crank arm off. The self-extractor obviously doesn't have enough to handle a 6 year crank that's never been taken apart. For reference, I've tried both a 18" breaker bar and cordless impact driver.
Any suggestions for how to loosen the crank? Hammer? Heat?
#2
Banned
External bearing BB so Its not that Old.
Corrosion/ rust is always a possibility on Mountain Bikes ..
Can you use a regular crankarm extractor, take out the self extractor ring.. ?
I stripped a crankarm, with a self extractor ring doing the damage.
Go to a Well equipped bike shop? It's worth a visit..
Corrosion/ rust is always a possibility on Mountain Bikes ..
Can you use a regular crankarm extractor, take out the self extractor ring.. ?
I stripped a crankarm, with a self extractor ring doing the damage.
Go to a Well equipped bike shop? It's worth a visit..
#3
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You could try greasing the top of the self-extracting bolt; there is a lot of pressure/friction between it and the FC-35 and some lube might help provide just that little bit of extra pressure that could pop off the arm.
Squirt in some penetrating oil to lube its threads as well.
You could also see if you can get a pair of Jacobs chuck wedges behind the arm to add their pull to the extractor.
Squirt in some penetrating oil to lube its threads as well.
You could also see if you can get a pair of Jacobs chuck wedges behind the arm to add their pull to the extractor.
#4
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Sounds like you're doing everything right. Have you tried standard stuck crankarm things like riding it around with the bolt loose and bouncing on the pedals alternating the horizontal position of the cranks?
#5
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One method I've had good success with is to back off the bolt as far as you can so it's pushing to it's max. Now place a hex hey or punch into it, and drive it with a non-steel mallet, my favorite is a wooden or paper one, but just anything is acceptable except steel.
The blow adds additional force above that you've already loaded and drives the spindle, while the crank's small momentum is enough for this trick to work.
The blow adds additional force above that you've already loaded and drives the spindle, while the crank's small momentum is enough for this trick to work.
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FB
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
Last edited by FBinNY; 10-02-16 at 08:57 PM.
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Sorry I don't have anything constructive to add, but just to clarify, it's a Hollowtech II crankset. The original Hollowtech Shimano cranks also use self extractors, but use Octalink bb's instead of outboard Hollowtech II bearings.
#7
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Thread Starter
One method I've had good success with is to back off the bolt as far as you can so it's pushing to it's max. Now place a hex hey or punch into it, and drive it with a non-steel mallet, my favorite is a wooden or paper one, but just anything is acceptable except steel.
The blow adds additional force above that you've already loaded and drives the spindle, while the crank's small momentum is enough for this trick to work.
The blow adds additional force above that you've already loaded and drives the spindle, while the crank's small momentum is enough for this trick to work.
#8
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Good suggestions. Unfortunately, the wheels are currently in the shop getting the bearings replaced. I'm taking the cranks off so that I can do a full rebuild of the suspension pivots.
I'll have to give that a try. Looking at it more carefully I may be able to put something in the drive side, and whack the bolt from the back-side. I just need to find a ~20mm wooden rod...
I'll have to give that a try. Looking at it more carefully I may be able to put something in the drive side, and whack the bolt from the back-side. I just need to find a ~20mm wooden rod...
1, the pusher rod doesn't need to be wood, just the striking hammer.
2, my method doesn't stress pats significantly, but driving the bolt outward risks breaking the removal ring, so proceed with due caution.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#9
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Thread Starter
I got it out. I tried several methods most of which didn't work.
Ultimately, hitting the NDS crank-arm with a rubber mallet was enough to loosen it a hair. Once it moved 0.5mm or so, I was able to use a breaker bar and the self-extractor to finish it.
So follow-up question.
I bought the bike used, and the plastic thread protector for the Shimano tool is missing. Does anyone have a recommendation for something to put in there to keep the threads clean?
Ultimately, hitting the NDS crank-arm with a rubber mallet was enough to loosen it a hair. Once it moved 0.5mm or so, I was able to use a breaker bar and the self-extractor to finish it.
So follow-up question.
I bought the bike used, and the plastic thread protector for the Shimano tool is missing. Does anyone have a recommendation for something to put in there to keep the threads clean?