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  1. #1
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    Be VERY careful with 3T carbon bars & stem

    I feel kind of like Captain Obvious here, but just in case, I thought I'd save someone else some expense and aggravation...

    I really don't want to start a new debate about why anyone would want to run carbon bars, but thought I'd pass this along.

    I installed 2 sets of 3T Ergo Nova Team (carbon) bars on 3T Arx Team (aluminum) stems. Since they were carbon bars, I was VERY careful and used a torque wrench (used both the Bontrager and Ritchey wrenches that are pre-set to 5Nm, the torque clearly recommended on the stem), tightened the bolts in a cross pattern and made sure the gap at the top and bottom of the camp was the same. In fact the BARS say the max torque is 5.5Nm so I felt pretty safe tightening to 5Nm. I say I used both wrenches because I switched stems around a bit but all were 3T stems. Somewhere along the line, this happened: Be VERY careful with 3T carbon bars & stem-img_2042.jpgBe VERY careful with 3T carbon bars & stem-img_2046.jpg

    After taking this bike to the LBS who told me the bar was dangerously crushed, I took a very close look at my other bike that has a similar set-up and though much less obvious, it has the same damage. Again, I NEVER tightened the stem bolts with anything other than a torque wrench (and I know not not to use fixed torque wrenches to loosen bolts too).

    Advice from the LBS was to use friction paste (which I had as you can see in the photo) and DON'T tighten to the max ("recommended" in my book as a conservative engineer) torque. Just tighten until it feels snug and haul on the bars to make sure they don't move.

    They're going to try to warranty the bars with 3T, but I'm not optimistic.

    Here endeth the $700 lesson.
    Well, you know, that's just, like, your opinion man. - The Dude

  2. #2
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    What kind of torque wrench?
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  3. #3
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    Quote Originally Posted by OldChipper View Post
    ...(used both the Bontrager and Ritchey wrenches that are pre-set to 5Nm, the torque clearly recommended on the stem), tightened the bolts in a cross pattern and made sure the gap at the top and bottom of the camp was the same...
    Guess I included too many details for the modern attention span.
    Well, you know, that's just, like, your opinion man. - The Dude

  4. #4
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    It sounds like you did everything right. The only valid questions I can foresee 3T raising is calibration of the torque wrench. It would have to be pretty far off to lead to a cracking of the bar.

    Two unrelated questions: (1) where did you buy the bars, and (2) how dd the LBS determine the bars were "crushed"?

    If indeed they are truly crushed, and everything else is proper, I don't see why they wouldn't honor their warranty (2 years. right ?).
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  5. #5
    'brifter' is a lame word.
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    ^ Warranty^ issue if they're legit 3T. The ONLY time I've seen this happen on new stuff it was Deda forgery bar/stem. Lucky for us the national sales manager for Deda lives a couple miles away and he came over to check it out. Instantly declared them fakes.
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  6. #6
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    You sure those are crused and it's not just a wrinkle in the red sticker? Did you hear a noise? I assume you would if you indeed crushed 'em.

  7. #7
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    Quote Originally Posted by cxwrench View Post
    ^ Warranty^ issue if they're legit 3T. The ONLY time I've seen this happen on new stuff it was Deda forgery bar/stem. Lucky for us the national sales manager for Deda lives a couple miles away and he came over to check it out. Instantly declared them fakes.
    Where were these fakes purchased from?

  8. #8
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    VERY large, VERY reputable LBS in Boulder, CO that does lots of local and mail-order business (that should be enough for most local folks to figure it out). Forgery seems pretty unlikely unless it was a MASSIVE fraud as the bars were purchased about 6 months apart and one was an ErgoNova Team and the other an ErgoNova Team Stealth.

    They determined the bars were crushed by visual inspection by a couple of the guys there who are very experienced and with whom I've done a ton of business (i.e. they weren't just trying to make a quick sale). They said they've seen it before and it's usually engineers (like me), scientists etc. who often follow recommended specs to a "T." Thus my warning to others.

    I'll post what 3T says. I'd be more than happy to send them my wrenches so they can check the calibration.

    For locals who recognize the shop, I'd like to re-emphasize that I consider this LBS to be totally awesome. They've treated me VERY well and have always really gone out of their way to be helpful, find difficult-to-find parts, process warranties, help me out with complex build issues etc. They've offered to advocate for me with 3T as well. If forgery is involved, there's NO WAY they're at fault or trying to pass off counterfeit goods.

    P.S. Thanks for the opinion CXWrench; you're the expert.
    Last edited by OldChipper; 05-24-2015 at 05:12 PM.
    Well, you know, that's just, like, your opinion man. - The Dude

  9. #9
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    You pretty much eliminated the knock-off issue. My only thought is bad batch. It can and does happen, unfortunately. The good news is you spotted it.

    Looking forward to how this is resolved.
    "When man invented the bicycle he reached the peak of his attainments."
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  10. #10
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    Quote Originally Posted by Jay Strongbow View Post
    You sure those are crused and it's not just a wrinkle in the red sticker? Did you hear a noise? I assume you would if you indeed crushed 'em.
    I was wondering that too, but the words weren't even out of my mouth before the shop guys said: "Nope, that's crushed." I trust these guys implicitly, and they see a lot more of this kind of stuff than I do. I didn't hear any "snick" or "crack" type noises when tightening the bolts, just noticed the "wrinkle" after. I was working in a quiet environment too, so likely would have heard it if there was a noise involved.
    Well, you know, that's just, like, your opinion man. - The Dude

  11. #11
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    Quote Originally Posted by OldChipper View Post
    I was wondering that too, but the words weren't even out of my mouth before the shop guys said: "Nope, that's crushed." I trust these guys implicitly, and they see a lot more of this kind of stuff than I do. I didn't hear any "snick" or "crack" type noises when tightening the bolts, just noticed the "wrinkle" after. I was working in a quiet environment too, so likely would have heard it if there was a noise involved.
    Well they'd certainly know better than I especially having seen and touched them in person. But I still can't help but be less than sure they're crushed by looking at the pictures. Maybe take a penny or other coin and poke and prode around and see what that can tell you.

    Of course they could be a defect but given how much force they can take from yanking on them by a strong sprinter it's hard to fathom 5nm applied evenly could crush them. I know if a different type of force but still.

    Maybe what I'm seeing is just the picure lighting or my imatination and it isn't actually there but if you look at the bottom of the 3 on your top picture it looks like somewhat of a elongated bubble that I can't see being caused by crushing and would seem to lend some credence to the wrinked label theory. Can you see what I'd referring to? It looks like a bubble to me which would seem to indicate the lable isn't totally clued down to the carbon.

    Anyway, good luck with that.

  12. #12
    'brifter' is a lame word.
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    Quote Originally Posted by 5DII View Post
    Where were these fakes purchased from?
    You know, I can't remember. Somewhere online I'd guess. He brought them in to have them installed on a bike we were tuning. I went to tighten the faceplate up and noticed that the bar wasn't matching up w/ the stem very well...as in it wasn't exactly round. Measured it and it was out by over 1mm front to back vs top to bottom.
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  13. #13
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    I had the exact same thought when I first viewed the pics, hence my question about how it was determined that they were crushed. If competent mech's at a good, reputable LBS determined they were crushed, I certainly am in no position to question that. But if that red tape/sticker whatever it is moves that easily, I would think it should be able to be moved back just as easily. But then I really don't have clue without having the bars in hand.
    Last edited by ibericb; 05-25-2015 at 05:20 AM.
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  14. #14
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    I just checked my notes on a build I did a few months ago with 3T Ergonova Team bars and Arx Team stem. I tightened the stem to 3.5 Nm and used carbon paste.
    No slipping and, from what I can tell, no crushing.

    I wonder if you can lightly tap the bars with a hex wrench and hear a difference in sound if the clamping area is crushed.

    I'll assume the shop is X and I agree, those folks are great.

    I have heard a CF seat post make the crack sound whilst being tightened. Everyone in the shop went white. That post was being tightened to "Max" spec too. That's when I learned to be suspicious of the "Max." numbers and to avoid them.

    I also wonder about the 4 bolt "max" too. What's the clamping force of 4 bolts @ 5Nm vs one bolt @ 5Nm. Just curious.
    Last edited by Sumguy1; 05-24-2015 at 06:47 PM.

  15. #15
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    You mention Bontrager & RItchey preset torque wrenches. I wouldn't trust them to install components. A proper dial set torque wrench that is returned to zero after use is all I trust.

  16. #16
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    I've had smooshes like that on FSA carbon bars. It was due to the decal under the clearcoat getting compressed, not the underlying CF being compromised.
    ... 'cuz that's how I roll.

  17. #17
    wim
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    Quote Originally Posted by looigi View Post
    I've had smooshes like that on FSA carbon bars. It was due to the decal under the clearcoat getting compressed, not the underlying CF being compromised.
    Seen the same dimple with other carbon bars that had been clamped with about 5 Nm and were clearly not damaged structurally, so add me to the people who question that quick "nope, that's crushed" judgement.

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  19. #19
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    Quote Originally Posted by froze View Post
    Welcome to the world of Carbon Fiber.
    Except its not clear there's any carbon fiber damage at all.

    I will say that the part of the discussion revolving around whether or not there is structural damage is somewhat academic. Even without structural damage this is a clear warranty case, and calls for a replacement. But, in case anyone is interested, my money is on the no-structural-damage hypothesis, even though I would have the bar replaced, of course, if it was me.

  20. #20
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    Quote Originally Posted by Pirx View Post
    Except its not clear there's any carbon fiber damage at all.
    Yup. Looking closely at the pics, the apparent defect in the read/white is about perfectly symmetric on both sides, and it's raised, as if it stretched, slid and bunched up. It's not what I would expect for an underlying structural failure.

    I will say that the part of the discussion revolving around whether or not there is structural damage is somewhat academic. Even without structural damage this is a clear warranty case, and calls for a replacement. But, in case anyone is interested, my money is on the no-structural-damage hypothesis, even though I would have the bar replaced, of course, if it was me.
    It strikes me as a defect too. How this is handled will say a lot about 3T.
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  21. #21
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    Max torque is maximum, not recommended. Yes, tighten until the bar is solid, then stop. Do not tighten to 5.5nm and see if it is tight.

    Use a real torque wrench, that zeros after use. Torque keys are for carrying in a saddlebag not for workshops.

    My PRO carbon bars are fine after two years, carbon yes but unfashionably heavy. Anytime a product is superlight it will be more prone to break. Lots of superlight aluminum bars broke back in the olden days. Handlebars are the last place to go superlight.

  22. #22
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    Quote Originally Posted by looigi View Post
    I've had smooshes like that on FSA carbon bars. It was due to the decal under the clearcoat getting compressed, not the underlying CF being compromised.
    Same here on Easton carbon bars. No structural damage.

  23. #23
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    Thanks for all the input guys. I will post what 3T says. Will take me a day or two to get the replaced bars back to the shop then, I'm sure, a little while to ship and examine by 3T.

    FWIW, I've checked the torque keys against a "real" torque wrench and they seem to be dead-on balls-accurate (obscure "My Cousin Vinnie" reference).
    Well, you know, that's just, like, your opinion man. - The Dude

  24. #24
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    After your post I checked and I have the same problem.

    Mine look the same as yours. Same bars and same stem. I sent a note to 3T and will see where it leads. They do not flex and do not look compromised, but I damn sure don't want them breaking.

    I'll post my findings and follow this. Thanks for posting this information.

    I sent 3T some photos, but have not had any luck posting them here. I keep getting a "file error" message.

  25. #25
    tka
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    Quote Originally Posted by OldChipper View Post
    FWIW, I've checked the torque keys against a "real" torque wrench and they seem to be dead-on balls-accurate (obscure "My Cousin Vinnie" reference).

    As part of an MSA at work we checked 3 torque keys 3 people had with unknown histories vs 4 calibrated production torque wrenches. The 3 torque keys had a tighter distribution and less variance than the calibrated production torque wrenches, and significantly tighter distribution operator-to-operator. All the torque wrenches had less than 7% variation to the set torque so I don't know how accurate you want to be, however.

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