# Torque on Stem Bolts?



## TiCoyote (Jun 28, 2005)

I was adjusting a few things on the bike, and I wanted to torque down the headset and stem a bit. The stem reads "recommended torque, 4.5 NM." It's a carbon Specialized Stem, and the steerer is carbon too. 

I found that if I torqued down to 4.5, the top bolt looked much tighter than the bottom one. The gap was closer. 

Also, if I turned the bars all the way to the left, there was rubbing. I thought that it might be the top bolt, the one that tightens on the headset, so I pulled everything apart, put in a little grease, and put the top bolt back on looser, but it was still rubbing. It wasn't until I tried the stem bolts looser that the rubbing went away. 

Has anyone else found that the specs stamped on the stem are too high? I don't want to damage anything by riding with the stem too loose. 

I tried it with 3.5 NM, but that was still too high. Now it's just hand-tight to what seems appropriate.


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## mfdemicco (Nov 8, 2002)

TiCoyote said:


> I was adjusting a few things on the bike, and I wanted to torque down the headset and stem a bit. The stem reads "recommended torque, 4.5 NM." It's a carbon Specialized Stem, and the steerer is carbon too.
> 
> I found that if I torqued down to 4.5, the top bolt looked much tighter than the bottom one. The gap was closer.
> 
> ...


I'm not sure what you mean by rubbing. The bolts should be tightened a little at a time in equal amounts, then brought up to final torque with the torque key or torque wrench. Is the bolt bottoming out in the thread?


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## tlg (May 11, 2011)

TiCoyote said:


> I was adjusting a few things on the bike, and I wanted to torque down the headset and stem a bit.


 You don't torque a headset.



> I found that if I torqued down to 4.5, the top bolt looked much tighter than the bottom one. The gap was closer.


 Whenever you have multiple fasteners to secure something, you gradually and alternately tighten each until they are to full spec. Just like the lugnuts on your car. You don't fully tighten one lugnut then move to the next.



> Also, if I turned the bars all the way to the left, there was rubbing.


Rubbing of what?


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## TiCoyote (Jun 28, 2005)

When I turned the bars all the way to the left, I felt resistance for the last few inches.


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## tlg (May 11, 2011)

TiCoyote said:


> When I turned the bars all the way to the left, I felt resistance for the last few inches.


What did you torque your headset to?


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## Gregory Taylor (Mar 29, 2002)

TiCoyote said:


> When I turned the bars all the way to the left, I felt resistance for the last few inches.


My guess is that resistance is the brake/shifter cables wrapping around the head tube and pulling tight as you turn the bars.

Of all of the parts on a bike, it is headsets - especially threadless headsets - that seem to totally mystify people.

Frankly, reading your original post, I can't make heads or tails of what you are doing. Are you talking about torqueing down the faceplate for the bar, or the pinch bolts where the stem slides onto the fork? I got it that the top cap is in play here as well. 

I would put the tools down until someone who knows what they are doing shows you how to adjust a headset.


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## robt57 (Jul 23, 2011)

TiCoyote said:


> When I turned the bars all the way to the left, I felt resistance for the last few inches.



Making sure that is NOT tight cables/housings, loose it all up so you can drop the fork 1" or more and maybe spin the bearings 90^ left and see if that will do it...


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## TiCoyote (Jun 28, 2005)

Okay, I'll try this again. 

I tightened the bolts on the stem that hold the stem to the steerer. I tightened them to 4.5 NM, because that's what is stamped on the stem. When I turned the bars all the way to the left, I felt some resistance for the last few inches. It wasn't a cable binding against anything. 

I tried loosening the stem bolts, then loosening the top bolt (the one that pulls up on the fork), and then I tightened the stem bolts back to 4.5NM. Same result. I tried loosening them and then re-tightening them to 3.5 NM. Same result. I finally loosened them and retightened them without the torque wrench, just a hex key, and the resistance was gone. 

I didn't use a torque wrench on the headset bolt. I just made it snug.


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## Gregory Taylor (Mar 29, 2002)

TiCoyote said:


> Okay, I'll try this again.
> 
> I tightened the bolts on the stem that hold the stem to the steerer. I tightened them to 4.5 NM, because that's what is stamped on the stem. When I turned the bars all the way to the left, I felt some resistance for the last few inches. It wasn't a cable binding against anything.
> 
> ...


If it were me....

Loosen the two pinch bolts on the stem/steerer connection.

Loosen the top cap on the head set. Hell, take it off. 

Grab the stem, and wiggle it around on the fork steerer. Get it loose so it can move around fairly easily on the steerer.

Straighten the stem.

Thread the top cap back on. Tighten the top cap 'til you just start get resistance (i.e. it has pulled the fork and stuff up reasonably snug and there is maybe a LITTLE drag on the bearing). Then add 1/4 turn.

Throw your leg over the bike, straddle the top tube, and apply the front brake. Rock the bike back and forth on the front wheel. Check for movement of the stem or fork that would indicate that it is loose. Bounce the bike on its front wheel a couple of times. Listen for knocking or rattles that would indicate that the headset is still loose. Also, check to see if the top cap has loosened any. If so, snug it back up. Repeat until the noises cease and you are satisfied it is tight enough, but not too tight. 

Turn your attention to the pinch bolts. Snug them up in tandem a quarter turn at a time until reasonably tight. A quarter turn on one, then the other. Finish with the torque wrench to the specified spec. 

Bounce the bike a few more times on the front wheel. Listen for knocking or rattles that come from the headset. This would indicate that the headset is still loose, dammit. 

If you still have binding after all of this, it could be a couple of things. A bad bearing, perhaps. Or a bent steerer (not terribly likely with carbon). Cocked races. Or a tight cable.


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## ibericb (Oct 28, 2014)

I just did some checking - Specialized doesn't currently offer a carbon road stem. But they did in the past, and in 2007 there was a major recall of all the Mg faceplate carbon road stems. How old is this stem?


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## TiCoyote (Jun 28, 2005)

Yep, that's pretty much everything I did. It's just that 4.5 NM was too tight.


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## TiCoyote (Jun 28, 2005)

ibericb said:


> I just did some checking - Specialized doesn't currently offer a carbon road stem. But they did in the past, and in 2007 there was a major recall of all the Mg faceplate carbon road stems. How old is this stem?


You're right. It's an alloy stem.


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## Gregory Taylor (Mar 29, 2002)

Just to be clear, you didn't put a torque wrench on the top cap, right?

The only other thing that I can figure is that torqueing the two pinch bolts to 4.5nm is deforming the steerer and causing the drag. Which is a little disturbing. Because otherwise it shouldn't add any preload to the headset bearings. 

Is this a new stem? Did it come with the fork/bike?


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## Gregory Taylor (Mar 29, 2002)

Is it compatible with a carbon steerer? Some aren't. If it isn't compatible, your symptoms begin to make more sense.....


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## TiCoyote (Jun 28, 2005)

All the parts are original to the bike. I did not use a torque wrench on the top cap.


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## Gregory Taylor (Mar 29, 2002)

TiCoyote said:


> All the parts are original to the bike. I did not use a torque wrench on the top cap.


Well, ya got me stumped. 

Unless it is something obvious that everyone is missing, I might take the fork off of the bike and start from scratch. Check the bearings, see that the steering tube looks to be in good shape (no crimps or bulges), etc.

Good luck.


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## Camilo (Jun 23, 2007)

For the life of me I can't figure how the tightness of the stem/steerer bolts could possibly affect binding when the handlebars are turned. There is no movement between the stem and the steer tube. Those bolts have nothing to do with the load on the bearings (that's all done by the top cap bolt).

Please explain how you think that the stem bolts affect the bearings - e.g. the binding you feel turning the handlebars.


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## TiCoyote (Jun 28, 2005)

Camilo said:


> For the life of me I can't figure how the tightness of the stem/steerer bolts could possibly affect binding when the handlebars are turned. There is no movement between the stem and the steer tube. Those bolts have nothing to do with the load on the bearings (that's all done by the top cap bolt).
> 
> Please explain how you think that the stem bolts affect the bearings - e.g. the binding you feel turning the handlebars.


I can't figure it out either. That's why I posted.


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## ibericb (Oct 28, 2014)

Any chance this is one of the Specialized multi- fit stems with the shims for angle?

If not, I'd remove the stem and any spacers completely, and carefully inspect the steerer.


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## ziscwg (Apr 19, 2010)

ibericb said:


> Any chance this is one of the Specialized multi- fit stems with the shims for angle?
> 
> If not, I'd remove the stem and any spacers completely, and carefully inspect the steerer.


I was thinking the same thing.

He's got something angled just a bit. Headtube bearings, spacer, something is binding the steer tube like like a big juicy steak


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## ibericb (Oct 28, 2014)

ziscwg said:


> I was thinking the same thing.
> 
> He's got something angled just a bit. Headtube bearings, spacer, something is binding the steer tube like like a big juicy steak


4.5N-m (40 in-lbs) in't much torque, and shouldn't lead to a bunch of clamping force. The only way I can foresee it binding under stem clamping force alone when turning the fork to an extreme, other than brake or shifter cables hitting a limit, is either the steerer tube is becoming distorted at low clamp force, or something is getting wedged between the steerer tube and the headset. The concern with distortion is a possible crack in the steerer tube. The wedge possibility might be related to one of the shims that Spec's multi-position stems use.

If all of that is good, then it's time to pull the fork, inspect the steerer tube, bearings, etc. very carefully then reassemble with care.


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## ibericb (Oct 28, 2014)

Note added - double check your torque on the expansion plug. I had a vague recollection of this thread, and with some searching found it. It seems almost incredible to me that an expansion plug could lead to the kind of bulging and problems that was described, but I have no basis to question it.


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## TiCoyote (Jun 28, 2005)

Well, I took everything apart, cleaned out all the crap, put in some fresh grease, and then reassembled and torqued to spec. Seems to be working fine now. Another mystery is resolved yet unsolved. Thanks for the advice.


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## oldcannondale (Jul 23, 2011)

outstanding, I think ziscwg is onto something? lots of great ideas


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## ziscwg (Apr 19, 2010)

oldcannondale said:


> outstanding, I think ziscwg is onto something? lots of great ideas


What to use steak to fix your steer tube??? It's unconventional, but the results speak for themselves with a big MOOOOOOOO!!!!!!!!!!


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## robt57 (Jul 23, 2011)

If the multi angle adjust Spesh Stem and the bevel piece is inserted from the top. As in; someone flipped the stem and did not take the shim out and reinstall from the bottom. This wonks out and loads the headset in a very unsymmetrical way and it can muck things up...


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