Torque specs for carbon bars?

[brett]

Anyone know the torque specs for Specialized carbon bars? I'm guessing it shouldn't be much different from other carbon bars but I can't find the specs anywhere.

Also, what are the recommendations for preping? I've read Tacx dynamic paste is good and seen other tips recommended but what do you all do?

[2wheel_lee]

Originally Posted by bmmh

Anyone know the torque specs for Specialized carbon bars? I'm guessing it shouldn't be much different from other carbon bars but I can't find the specs anywhere.

Also, what are the recommendations for preping? I've read Tacx dynamic paste is good and seen other tips recommended but what do you all do?

What do I do? For my better health, I don't use carbon bars on mountain bikes. I've seen way too many injuries to justify saving 20 grams.

I've used Tacx paste on carbon seatposts, but never bars. Seems like a good idea, though.

Use the torque specs specified by the stem manufacturer. Some stems have the torque spec shown in the clamping area of the stem (if not visible from the outside). Remove the bars and check on the inside for the torque specs.

[Team Smitty]

I don't know the torque spec, but will suggest you file a very small radius on the edge of your stem. This will help reduce the presence of a "stress riser" at the bar stem interface.

[SAR_boats]

If you hear a cracking noise then it is 5 ft-lbs less. (don't do this, I am only kidding)

[krash]

Most stems list the max. torque that the bolts can take NOT to recommended torgue for the handlebars! I have learned my lesson on over tightening stems bolts with carbon bars and ALWAYS us a torque wrench. http://www.eastonbike.com/downloadab...-06-2Bolts.pdf

[2wheel_lee]

I guess in the end...

1) If you don't torque them tight enough, the bars slip.

2) If you torque the bolts too tight, the bars will break.

3) If you torque the bolts just right, the bars will break...eventually.

The lesson learned here are that the it's better to ride with loose bars than bars that break. All those who claim that they haven't broken their bars either ride casual XC or road, or they just haven't broken them yet. Give 'em time (although if you must run carbon bars, replace them from time to time).

[Rockinthecasbah]

i just put carbons on my 29er , shshhh dont tell me these things

[Mudman]

I had actually thought about carbon bars for the Demo 8 and 4X bike- but after some serious thought and asking a few people it was concluded that carbon bars were not suitable for my crash prone style of riding. Carbon looks awsome on cars and what not, but I just don't feel safe with that as my only resort. Rather have bent bars that can still be used after a crash as opposed to broken bars or maybe one half bar to get back to my car or something.

[Rockinthecasbah]

well hopefully i dont pull one of my flip over the bars clipped in off the side of the trail moves at chino tommorow

[Mudman]

Originally Posted by Rockinthecasbah

well hopefully i dont pull one of my flip over the bars clipped in off the side of the trail moves at chino tommorow

you'll be fine, just don't do any hucking on it!

[singleminded]

Snap, crackel, pop.........

I have ran them for years......they are fine. Most specs are what the stem manuf recommends. i do the 48in lbs for the thomson on my carbons. 5 years on the LP's and 3 on the Weyless and no breakage yet

[Schecky]

I just replaced my carbon bar - with another carbon bar. About five good years on them. Very little hucking done on them - mostly XC miles.
I am a clyde and have had no issues.
I think they break about as often as any other component.

I would always use a torque wrench.
Make sure that your shifters and brake levers are just barely tight so they spin if you tumble.
Do inspect them very carefully after any crash.

[nick]

Seriously? Is there an epidemic of carbon bars "snapping" all over the trails? I've got carbon bars and know a lot of guys who ride carbon bars and I've never seen a broken set. Seems like if you take care of your gear by tightening them to spec and replacing if they get a bad scratch or gouge from a crash, you should be okay. I don't think some of the more reputable manufacturers would sell them if they were "snapping" all the time.

Is the problem more with guys trying to do drops and downhill using XC bars?

[brett]

Originally Posted by 2wheel_lee

Use the torque specs specified by the stem manufacturer. Some stems have the torque spec shown in the clamping area of the stem (if not visible from the outside). Remove the bars and check on the inside for the torque specs.

I haven't installed the bar yet and looked all over it for torque ratings but found none. I can't track anything down on the web, either. I think I will use the specs Thomson gives for their stems.

But I was also wondering what the torque people use for the brake/shifter clamps and lock-on grips. Seems like for these, "enough not to twist in normal use but to twist in a crash" is the theme.

[brett]

Originally Posted by Team Smitty

I don't know the torque spec, but will suggest you file a very small radius on the edge of your stem. This will help reduce the presence of a "stress riser" at the bar stem interface.

I thought about this. Most of the picks I've seen of failed bars seem to be at the brake levers. I looked at my levers and it looks like they are bevelled 45 degrees. Might be wise to just file it to a more rounded bevel.

[1TrackMind]

Originally Posted by Rockinthecasbah

well hopefully i dont pull one of my flip over the bars clipped in off the side of the trail moves at chino tommorow

As long as you are still clipped in you will land on your head, not the bars...your bars will be fine