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Discussion Starter · #1 ·
I cannot.

I used an old handlebar as leverage and still can't get it to budge. I read on a post on Pinkbike where a SRAM rep said to use an impact gun. I can't really picture using any kind of impact tool on a bike part.

Anyone else have problems breaking the bolt loose?
 

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Elitest thrill junkie
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I can't really picture using any kind of impact tool on a bike part.
Marzocchi. Footnuts.

If this is the normal fixing bolt and not the "do not remove" bolt from the opposite side, it sounds like it's been overtighened, but they can be on there pretty solid sometimes. Are you using a cheater bar? I have several diameters of PVC pipe for these concerns and others. The old standby is to get a mallet and bang the cheater/breaker bar in the direction of loosening it, just don't bang the frame. Taking a heat-gun to it prior or even a hairdrier on high would possibly be helpful.
 

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Discussion Starter · #3 ·
The bolt is on the drive side of the crank.

I tried using an old aluminum handlebar over the 8mm hex wrench. The bar looked like it was about to snap. I tried using a rubber mallet on the hex wrench too...no go. I even tried standing on the wrench using my body weight...still no go.

I'll probably end up taking it to a shop and see if they can muscle it loose.
 

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Elitest thrill junkie
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The bolt is on the drive side of the crank.

I tried using an old aluminum handlebar over the 8mm hex wrench. The bar looked like it was about to snap. I tried using a rubber mallet on the hex wrench too...no go. I even tried standing on the wrench using my body weight...still no go.

I'll probably end up taking it to a shop and see if they can muscle it loose.
I'm not using hex wrenches for this kind of stuff, I'm using breaker-bars with hex-sockets. Attach my smaller diameter PVC cheater bar to the breaker bar if necessary. You want lots of overlap. Also if necessary, take off pedal and insert larger-diameter PVC cheater over the crank arm, to give opposite force. In other words, I keep "stepping it up". These are useful for other things too, like setting crown races or seals, etc.
 

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Yeah, I think there's an issue with some of those cranks. I've had two sets of Dub cranks that did this. Even well-greased and torqued to spec, it almost seemed like they over-tightened themselves.

I'm talking TIGHT.

What I did: secure the NDS crank arm to the chainstay; I used big velcro straps. Then 8mm hex on a ratchet and a 3-foot breaker bar. It lets go with a bang. Probably a warranty issue.
 

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Never trust a fart
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Yeah, I think there's an issue with some of those cranks. I've had two sets of Dub cranks that did this. Even well-greased and torqued to spec, it almost seemed like they over-tightened themselves.

I'm talking TIGHT.

What I did: secure the NDS crank arm to the chainstay; I used big velcro straps. Then 8mm hex on a ratchet and a 3-foot breaker bar. It lets go with a bang. Probably a warranty issue.
It's not a warranty issue. It's an installation issue by the bike manufacturers. They over tighten everything. Once the cranks are loosened and retightend, they are easier to get loose the next time with just a hex socket and breaker bar. No extension needed IME. Yes they are tight, but nowhere near as tight during first disassembly.

Sent from my SM-G930V using Tapatalk
 

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I don't have a DUB crank, but the fixing bolt on my SRAM crank was the same, and will continue to be.
I watched a couple youtube videos of how to, and the warnings it was tight. Since i was new to me, I ended up at the shop because I couldn't get it removed. Watching the shop guy with a wrench and a 3' pipe to finally break it loose was pretty surprising.

I have removed it at home 2x since, and it's been tight each time. Shop guy warned me that that was the nature of the design of these type cranks. I had mentioned that maybe I should remove it once in a while -I was told doesn't matter, and it would be tight if I removed it the following day.

I usually end up finding a solid surface to have the pedal rest on. Get the tools/cheater all set then lean over the seat to prevent bike from lifting when I loosen. The cheater bar I use is half of a floor jack handle.

Once removed, I cleaned all the parts, etc (replaced chain rings) and greased the threads. The spline. The shaft. All the good stuff and it still takes a lot to budge.

Good luck!
 

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No Clue Crew
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That wasn't my experience. I had two cranksets with this issue, both removed and reinstalled multiple times. Greased and torqued to spec each time. On subsequent removal, the fixing bolt was radically tighter than when installed. I know it seems impossible and I have no explanation, but it definitely happened to me on more than one Dub crankset.

FWIW, I've had multiple other SRAM cranksets (including two on my bikes right now) that have never had this issue.

It's not a warranty issue. It's an installation issue by the bike manufacturers. They over tighten everything. Once the cranks are loosened and retightend, they are easier to get loose the next time with just a hex socket and breaker bar. No extension needed IME. Yes they are tight, but nowhere near as tight during first disassembly.

Sent from my SM-G930V using Tapatalk
 

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Just went through this. What a *****.

NX Eagle DUB crankset...on one of the arms, the pedal threads shat themselves so I had to replace the crankset. Went to loosen the crank bolt, bastard wouldn't budge, at all! For sure thought I was going to have to bring it to the LBS. After a bit of thinking, I ended up taking some speaker wire and basically wrapped the crank arm to the chainstay to hold it and that worked.
 

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^^^ oxygen free copper will maximize power transfer.

What I do is stand beside the bike reach over the top tube with my right arm and grab the wrench with it extending toward the back of the bike, and hold the left crank arm also extending toward the back of the bike and exert the appropriate force, pulling on the left and pushing on the right. Your hands are working in equal and opposite directions but will tend to tip the bike to the right, which you prevent by having the top tube in your armpit.

Advanced (quasi dangerous) method. Put he left pedal forward, the wrench toward the back of the bike, stand astride the bike on the pedal and wrench, and bounce on the pedal and wrench. Hold on to something and be prepared for when it lets go.
 

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I tried everything and the only thing that seemed to work was literally tying the crank arm to the bike. Then I had to use all my weight to break it free. Seems like all that shouldn't be necessary IF installed properly in the first place.
 

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I've seen many tie the crank arm to the chain stay, my LBS did that for my first removal.

I just position the pedal on a flat surface at the appropriate height. Unfortunately the bike wants to left, so chest on the seat is required to hold the bike down.

A few varied suggestions in the thread but sounds like they all have the same result.
 

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EAT MORE GRIME
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impact doesn't mean wreck your bike...unless you use a handheld hammer impact

use an impact drill and bit
that's what it do, knocks bolts till they wiggle free, by the micron

I use impact driver to get rusty spud cleats off my shoes, to save the bolt head
from getting wrecked
 

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Elitest thrill junkie
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impact doesn't mean wreck your bike...unless you use a handheld hammer impact

use an impact drill and bit
that's what it do, knocks bolts till they wiggle free, by the micron

I use impact driver to get rusty spud cleats off my shoes, to save the bolt head
from getting wrecked
Getting off should be no problem. For the old Marzocchi foot nuts you needed it for this and usually to put them back on, but you had to be careful with the latter because too much/long and it would snap the damping/dummy rod. But yeah, doesn't do anything else, the nature is impact and it's necessary in a few cases.
 

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Discussion Starter · #17 ·
I just ended up taking it to the bike shop. They put the bike on a stand...one held the crank...and the other used a pipe over the hex wrench. The mechanic put his weight on the pipe and the bolt broke loose.
 

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I've been seeing sram alloy spindle cranks with seized bolts in them all the time. It doesn't matter what you put on them for grease, they get stuck. It sucks.

I've always got them to break free but the shockwave that hits when it breaks free hurts a lot and has actually given me a headache.

I've even re installed a crank and barely torqued it. I then had to take it off again 10 minutes later and it was seized up. I took a dub crank off my new MTB the other day and it was seized up.

I basically never want to touch anyone's sram bb30 or dub crank ever.

In response to the impact gun. Never use an impact on a bike with a power meter. You will kill the strain gauges. But this was one of those I'm out of ideas to remove this bolt situations. And the bolt never came out. I had to drill all the way through it. Hollowgram crank w/o the steel washer on the bolt. Bolt face bonded to crank arm.
 
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