SRAM DUB Crankset removal

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SRAM DUB Crankset removal
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Posted: Sep 4, 2018 at 18:05 Quote
Trying to remove the crankset from my brand new Mondraker with SRAM DUB bottom bracket and NX Eagle Cranks... Using an 8mm hex on the drive side and trying to turn the hex in a counter clockwise direction and I can't get the thing to budge! I feel like I'm going to break something... What's the trick? Do I need to loosen the preload on the non-drive side first(I didn't think that's needed for crank removal)?

TIA!

Posted: Sep 4, 2018 at 20:28 Quote
Hi,

No tricks. Just use an old handlebar or pipe as leverage. No need to loosen the preload. Yank it couple times and bolt will loosen. Yes, the sound feels like something gonna break.

Posted: Sep 6, 2018 at 8:20 Quote
lepak1corner wrote:
Hi,

No tricks. Just use an old handlebar or pipe as leverage. No need to loosen the preload. Yank it couple times and bolt will loosen. Yes, the sound feels like something gonna break.

That did the trick. Thanks!

Posted: Sep 22, 2018 at 4:25 Quote
Hi there guys, I've had no problem in removing the 8mm, but i'm really struggling to take the crank apart from this part. Seems well jammed onto the spline - and tricks?

Posted: Jan 10, 2019 at 21:19 Quote
I've come to the conclusion the Dub cranks are basically yet another defective SRAM design, like the elixer brakes and the reverb post.

I've got a 4' pipe extension on both the crankarm and the Allen wrench and nothing budged with serious torque, the pipes are flexing several inches each. It honestly feels like I'm going to break my carbon fiber frame before I bust these cranks loose.

I'm missing my Shimano cranks and the low torque, 5 mm pinch bolt design. Shimano engineering is so much more solid than sram's garbage.

Posted: Jan 11, 2019 at 7:42 Quote
Flowcheckers wrote:
I've come to the conclusion the Dub cranks are basically yet another defective SRAM design, like the elixer brakes and the reverb post.

I've got a 4' pipe extension on both the crankarm and the Allen wrench and nothing budged with serious torque, the pipes are flexing several inches each. It honestly feels like I'm going to break my carbon fiber frame before I bust these cranks loose.

I'm missing my Shimano cranks and the low torque, 5 mm pinch bolt design. Shimano engineering is so much more solid than sram's garbage.

But SRAMs marketing is SOOOOOOOOO much better! That means you lie.

Are you using anything to keep the cranks in place while reefing? Like an old handlebar as noted above... I would wrap the old bar, preferably a riser, with an old tube so as to not damage the frame.

Posted: Jan 11, 2019 at 8:43 Quote
The problem isn't the cranks staying in place, the problem is the excessive torque I'm applying with the two extension pipes in opposite directions won't loosen the crank arm bolt. I'm worried about the opposing extreme forces damaging the frame.

It's hard to find an extension pipe to fit around the wide dub cranks, I took a hammer to a round pipe and ovalized it till it fit just right, and have the cranks wrapped to protect them.

A sram representative recommended using an impact wrench, which seems like a good idea since it seems like it might stress the frame less. So I'm off to the auto repair shop with my bicycle.

Posted: Jan 13, 2019 at 15:36 Quote
SRAM’s cranks are junk IMO. Shimano’s design is so much better.

Posted: Jan 14, 2019 at 19:23 Quote
My DUB cranks took a huge amount of force to loosen. They let go with a massive crack!

Posted: Jan 15, 2019 at 10:22 Quote
It might sound obvious, but did you put enough Grease on the splines and threads?

Posted: Jan 16, 2019 at 9:42 Quote
Flowcheckers wrote:
I've come to the conclusion the Dub cranks are basically yet another defective SRAM design, like the elixer brakes and the reverb post.

I've got a 4' pipe extension on both the crankarm and the Allen wrench and nothing budged with serious torque, the pipes are flexing several inches each. It honestly feels like I'm going to break my carbon fiber frame before I bust these cranks loose.

I'm missing my Shimano cranks and the low torque, 5 mm pinch bolt design. Shimano engineering is so much more solid than sram's garbage.
I would be sitting the bottom bracket on something flat with the crank on the same surface then get some leverage on the tool that way you are not stressing the frame as much.

Posted: Jan 16, 2019 at 11:48 Quote
AndriyR wrote:
It might sound obvious, but did you put enough Grease on the splines and threads?

Before I headed to the auto shop for an impact wrench I tried it again and they popped loose, I think the pressure from the self extracting bolt may have loosened them a little overnight. There was plenty of grease on the spines, its just the worst design they could ever come up with for removing cranks. Doesn't seem to be as much of a problem with the cheaper NX cranks.

Another bad thing about the design of these cranks is that it is a total engineering compromise to use the same bearing for 3 separate sizes of bottom brackets, instead of designing the bottom bracket to have the ideal size bearing for each bottom bracket respectively.

The DUB bottom bracket and crank system is actually built around a 30mm inner diameter bearing, with an outside diameter of 40mm. Not larger, but smaller than a stock BB30 setup. The whole point of BB30 was to increase stiffness (Or to at least market it), so SRAM has essentially compromised the stiffness improvements of BB30 with its compromised engineering of the DUB cranks. So if you buy aBB30 bike with DUB you are buying getting none of the extra stiffness, but you are getting the extra maintenance that BB30 sometimes requires. The only party who benefits from this horrible engineering nightmare is frame manufacturers who don't have to pay an extra nickle to put threads in the BB30 frames. If SRAM had any integrity they would call out these manufacturers for creating this nightmare but instead they have accommodated them and compromised the integrity of the bikes we ride.

Posted: Jan 19, 2019 at 23:13 Quote
So I just came across this topic and had to look into it. Sounds like the deal with the bearing diameters is correct, however I have to ask. Who cares? I can't recall ever replacing a bottom bracket because the bearings are actually worn out. Im sure it might happen every once in a while. So far, though, they've needed to go because of eventual ingress of water or other contaminants, causing some level of corrosion. I agree that having optimally sized bearings for each application might be nice, but having one bearing size and keeping overall cost down I think could be worth it.

Posted: Feb 25, 2019 at 16:52 Quote
I am running into the same issue, I cant get the damn cranks to break loose. You all are removing them from the drive side with an 8mm hex turning counter clockwise (right handed threads)?

Posted: Feb 25, 2019 at 17:03 Quote
Got them to break loose, didn't think I'd ever need to use a 2' breaker bar on my bike, thanks Sram.

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