SRAM DUB Road Crank install - 54Nm.... really?

Just had a rather worrying experience installing a SRAM Force dub chainset. Wound on the torque, I didn’t get to the 54Nm set on my torque wrench but the crank became stiff/not free spinning in the bb. So I tried to remove the crank and start again. Very very nearly rounded the crank bolt. Well, I did round it slightly but a hammer got the Allen bit further down the Allen bolt and just about managed to get it undone with a 2ft long breaker bar.

So… Does anyone NOT tighten to the recommended 54Nm? 54Nm just seems like I’ll never get the crank off again. Plus it wasn’t spinning freely when I got close to 54Nm.

I used 3mm of spacers on the drive side as recommended for a road PF86 shell so I’m struggling with why it wasn’t spinning. But I can work through that.

That aside, do I have to go to 54Nm???

Was your preload adjuster set all the way counter clockwise before installation? If not that could cause binding.

I just installed a set yesterday, 54 NM isn’t that much force. With the weight 1 foot from that axis that amounts to lifting about 40 lbs if my math maths.


I think it was.

Going to have to fit a new bolt first though before trying again.

Yep, 40ft lb is about the same on the imperial scale on the other side of my torque wrench.

Seemed quite a bit when I was winding it on, getting to the point where I was having to hold the other crank arm and brace against it (wheels etc aren’t on the bike as it’s not built up yet).

you might have had too many spacers or preload causing the crank to no spin, I have no issues torquing to 54Nm both mountain and road cranks, removing is tricky but easy once you come up with good strategy that works for you and your body

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So now I see how the preload adjuster works, if definitely wasn’t too much preload (it was fully wound in to its narrowest setting).

Just the issue of getting the retaining ring out now, which seems belligerently immoveable with a circlip plier tips. I assume there is a proper tool…

What is that you want to remove? The preload you can just spin and remove, make sure the thread part is attached too start spining and you can pull it out

I need to remove the retaining ring/bolt cover so that I can fit a new Allen bolt as I’ve mashed up/rounded this one getting it to 54Nm and then trying to undo it and making a mess of it. It is no longer the sharp hexagonal shape it needs to be for me to have any confidence in not getting it entirely stuck again.

The ring has 4 small holes in it rather than a larger Allen key head (than the main bolt) like some do. (The one on my rival 1x for instance)

Be sure to get the better version of the bolt.

I don’t know for sure, but I suppose all the recent models come with the steel bolt; older cranks may still have the aluminium one.

I see, there is a tool for that, that’s a self extracting bolt guess you need to be pulling out as you try to remove it, also a torx might help

Good luck!

Yeah, 54 Nm is a lot. The first time I put my cheap 8mm allen head socket in the hole and it wobbled a little, I went in search of a more precisely machined socket. A loose fit will strip it quick with torque that high. Took an 8mm allen head bolt to the hardware store and found a good one, with no slop. No issues after removing the cranks 8-10 times.

I’ve never had an issue with the 54 NM / 40 ft-lb. I have my SRAM MTB off pretty much all the time too to check / regrease when I get the bike real muddy (Upgraded my BB to BBInfinite which makes servicing super easy) and no issues with it. If you’re having issues, rounding the bolt, binding - You’ve got other stuff going on from incorrect assembly, to incorrect tools.

Removing the crank (not the cover) I use a generic 8mm Socket and my Electric Impact. Comes right off. On assembly, make sure everything is clean, threads lubed, not cross threaded, etc. And all of your spacers and preload needs to be correct.

To remove the cover, there is a specific tool. Here’s the pimp version of it:

So I have a version of the 4 pin tool arriving tomorrow, along with new bolt taking a little longer on the way but in the mean time I can swap the bolt off a Rival Dub chainset I have in my spares. Fresh socket bits ordered.

Preload was totally backed off, spacers were measured at 3mm for the drive side as per the SRAM manual for PF86.5. Loads of grease.

Struggling to understand where the issue was. If it was all too snug and too many spacers then surely the 54Nm gets reached as everything bottoms out and won’t budge any further? Too few spacers then also, do the splines not bottom out and 54Nm reached???

Should I try perhaps 2mm spacer instead of 3 and use the preload to take up the gap?

The preload should be backed off (zero preload) when you torque it. There should be a little gap, when it’s torqued, so that you can add some preload tension, but the preload can only take up so much gap (run out of threads) so the spacers are critical.

I don’t know if it was me or the bikeshop that assembled the bike, but something happened with my preload and the drive side spacer rubbed enough that the “SRAM DUB” logo (plus a little more, evidently) was ground off, so I needed to add a spacer(s). I was surprised how much difference one too many 0.5mm spacers changed the preload adjustment.

Yeah, so the preload was at its narrowest setting. I was worried I’d accidentally bought a “wide” chainset with the longer axle, but the rival chainset I have says DUB Wide on the axle, this just says DUB. And a comparison is that the wide is marginally longer.

Preload looks like it has enough adjustment for more than 1mm, so possibly I could remove the 1mm spacer, and try make up the gap with the preload???

When you assemble everything, with the preload backed off (out, away from the BB) all the way, you want there to be just a very small amount of play. So, spacers are used to space the crank such that there is that small amount of play after you torque it down, but that the preload adjuster can take it up. You then use a deadblow hammer to tap the crank all the way over to the Non Drive Side before just snugging down the preload adjuster.

If you don’t have that play, and there’s binding when you tighten it down with preload adjuster backed off, spacers are wrong is my take. (Or the crank, or the BB)

Something to keep in mind though, spacers are used on both sides of the crank / BB to keep the cranks centered in the frame so you can’t just decide to add / remove on one side as opposed to another. I will sometimes take a steel mm ruler and measure from the back of the crank arm to center of the water bottle cage bolts / bosses to make sure as I did have an issue with BB spacers like that once and had to screw around with different size spacers to make everything work.

TLDR: Use the correct spacers to keep crank centered, back off (out) the preload adjuster all the way, torque it down, tap to the Non Drive Side, take up that last bit of play with the preload adjuster.


I think the BB shell may be marginally wide, as when I had a Shimano crank installed I couldn’t get the little pin retainer between the pinch bolts to engage when the non drive side was properly fitted. It wouldn’t pivot into place, so I had to fill remove the bolts and put in square.

Will try less spacers for a starter.

The pin tool to remove the retaining ring has arrived at least, so I can crack on!

A bit of grease under the head of the self extracting bolt is a good idea, if you’re replacing it.

But I’ll say I’ve installed/removed SRAM Force AXS cranks, torquing to spec at 54Nm, at least a dozen times with no issues.

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So I have fitted the crank again. Fresh steel bolt from another dub crank. Allen bit all the way in. Paying attention to the torque wrench. Took it in stages, adjusting the torque incrementally each time it clicked out, up to 54Nm. 2mm spacer rather than 3mm. A fraction of play once fitted, easily taken out with the preload collar.

Bearings don’t sound amazingly smooth, a bit “whirry” as though something is rubbing but at least I can now set up the gears and stuff and see if I can be bothered to take it to bits another day. Or perhaps a ride might loosen it up??

you could have damaged the bearings, worth getting another dub bb since they are cheap, preload is a bit finicky. do the bearings feel smoother if you take out the preload?

Yes you do. There’s a lot of leverage trying to pry the crank arm off the splines - basically your body weight on a 170mm lever (about 125nm of constant prying). I’ve found myself flinging a few crank arms down the road before I looked at the Tq specs.

Bolt torque measurement isn’t an exact science despite it saying “54nm” because of a lot of factors. That bolt need to be all the way tight. Basically, go all the way tight using a 18in - 24in or so wrench.

You can ride the bike around your house, just carry the right size Allen key. If you start to feel some wobble side to side, stop and tighten it. Get a backup fixing bolt and a new Allen socket with a long insert, SRAM sells the bolts. Crank Arm Fixing Bolt SRAM | Worldwide Cyclery