# Stem Torque for Carbon Bars?



## Wheelspeed (Jan 12, 2006)

I picked up one of those affordable "Merek" CF bars from ebay. 139g in the 25.4, 650mm, 40mm rise for like $70 iirc.

No hex sockets for my torque wrench, so I just mounted them up not tight and rode a few times. One ride had a lot of log hopping. But no movement of the bars, so I hoped I didn't have them too tight. I later picked up some hex sockets. I couldn't find a suggested torque for Merek bars, but saw that Ritchey WCS CF suggested 5Nm. I went to torque mine, and turned the 4 bolts pretty far (1/2 a turn or so) before stopping. I lowered my torque setting to around 3.5Nm and set them to that. It seems like that should be plenty. 5Nm is a lot!

Any of you recall if your bars' suggested torque was less than 5Nm?


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## wordlesssong (Apr 26, 2006)

The recommended torque on Easton handlebars is 45 lb-in or 5.1 Nm. The maximum safe limit on Easton handlebars is 70 lb-in or 7.9 Nm. Your handlebar sounds similar from the recommended torque, so I'm sure it is well within the safe limit - you should be fine.


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## veritechy (Jan 2, 2008)

It also depends if you have 4 bolts or 2. Less torque for 4 bolts.


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## AndyBrn (Oct 7, 2008)

I run a Thomson X4 stem with Easton EC90 bars.

I've got mine tightened to 4nm.

4nm is the recommended torque setting by Thomson.


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## Wheelspeed (Jan 12, 2006)

Thanks guys. It didn't even cross my mind that the torque suggestion would come from the stem mfr., not the bar mfr. Now I just looked it up and my Race Face stem is suggested to be 6-7 Nm. I guess I'll tighten mine a bit more from the current 3.6 Nm or so.

Thanks again.


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## civil (Feb 13, 2008)

Another way you could do it is tighten the bolts until the bars do not slip. The use of carbon friction paste will help to lower the required torque to keep the bars in place.


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## AndyBrn (Oct 7, 2008)

I don't think that you're far off using your current torque setting.

I wouldn't go higher that 5nm and 6-7nm sounds too high to me.

Torque it up to 4nm and see if the bars move.

It's always better to start low and work up.

I think 4nm should be plenty.

Andy


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## herbn (Sep 17, 2005)

i think most carbon bars are reinforced in the clamping area,a metal sleeve,so i don't think the torque specs are any different.


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## TitusMotolite (Sep 14, 2009)

Nothing like the sound of crunching when tightening too much on a carbon tube! I've done a few times on Monkeylites...


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## louisssss (Jun 24, 2009)

is there any way of measuring how much to tighten a quick release seatpost clamp on a carbon seatpost? mine has been creaking sometimes when i hit some bumps...


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## herbn (Sep 17, 2005)

on my road bike when i put a giant stem on the shimano carbon bar,i tightened them pretty tight but i still heard a little tiny slip on the first ride.I rode right over to the local shop and tightened them to the torque that's printed right there on the stem, 57 inch/lbs.That is actually really freak'n tight for a little ti bolt but it hasn't slipped yet and i don't think it'll crush the bar, the clamp piece is quite thin so it would flex around the bar and kind of wrap around the bar as you tighten it.I can only imagine that maybe if the stem doesn't exactly match the bar or the clamp piece is misaliegned on the stem, there might be some crushing issues, i don't know about reg monkeylites ,are they the dh bars ?I have a couple of those i use them on my dh bike and my xc/freeride bike,with no crushing issues. I machine my own dh stems, they clamp very tight and solidly,the clamp piece is very thick ,but the hole for the handle bar is bored after the pieces are fit together so it all has to line up.


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