Heads up to those riding with carbon steertubes

Discussion in 'The Roadie Hangout' started by Judge Shredd, Jul 1, 2013.

  1. Judge Shredd

    Judge Shredd Member

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    Sometimes I get burnt out from riding on the dirt. So I decided to do a road ride from Irvine to PCH on the back bay loop. I don't like riding on the same roads as cars because I just find it too dangerous. So anyway on the way back I saw some chap walking his bike with something hitting the spokes. A few feet after I passed him I decided to go see if he needed help.

    He was all geared up is some fancy kit and had a pretty nice carbon bike with Dura-ace everything. I asked him what happened and he seemed pretty out of it. He said "it came off". I looked at his bike and noticed the chain was off so I asked him if it was the chain and he said "no the bars". I totally didnt even notice that the carbon steer tube on had snapped right at the bottom of the stem. We talked for a bit and he was getting someone to come pick him up, but it did look like he took a pretty good spill.

    Just saying, if you ride with a carbon steertube, this could happen to you.

    Anyway ,happy trails and be safe out there :beer:
     
  2. AKAlan

    AKAlan Member

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    Everything made of every material will break at some point. Myself and thousands of others have been riding bikes with carbon steerer tubes for many years now and since it's not a wide spread problem I would venture a guess that whoever installed the stem didn't use a torque wrench. My rigid SS uses a carbon steerer and I've never given it a second thought.
     
  3. me and my bike

    me and my bike New Member

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    [video]http://www.pinkbike.com/video/243228/[/video] ;)
     
  4. bing!

    bing! Active Member

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    gimme 5 minutes with a butter knife and a carbon frame and try those tests agin ;)

    a little nick at the right spot will bring down those load ratings exponentially
     
  5. RustyIron

    RustyIron Rob S.

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    I've broken a whole lotta aluminum. I've never broken any carbon parts.
     
  6. Allthatflash

    Allthatflash New Member

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    I think bones will break before carbon....
     
  7. trailninja

    trailninja Going Slideways!!!! Staff Member

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    Carbon > Aluminum

    In almost every aspect for riding.
     
  8. 2wheel_lee

    2wheel_lee Active Member

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    While not all carbon parts are bad, not all of them are good. ;)

    If you research a bit, you'll find that there are/were some road forks with carbon steer tubes that have a reputation for failure. In some cases, it appears so prevelant that it's been questioned why there wasn't a recall. One of those fork companies soon left the fork business. I think there may have been a bankruptcy involved, though I don't believe that the company fully went bankrupt.
     
  9. Judge Shredd

    Judge Shredd Member

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    [youtube]bwFYIiPFjVo[/youtube]
     
  10. ManInAShed

    ManInAShed New Member

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    That was a cute video.

    I'd like to see them do the demonstrations the other way round. Swing the underside of that composite DT onto the concrete, and then put it on the compression rack. Not so pretty now, is it...

    I love carbon composite when done well as much as anybody, and Santa Cruz definitely has their bikes actually tested before hitting the market, (the Chinese shops offer full R&D services as part of the package) but this video is pure silliness, and the glowing comments in that thread are telling of a forum full of impressionable kids.

    It's tempting to use composite in a steerer application. ...but even when you do it right, it still requires every person who installs a stem on one to do it properly, every time. I like Ti steerers.
     
  11. skflow

    skflow Member

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    I have 2 bikes with carbon steer tubes, but I do my own work and follow all the right installation procedures/precautions.
    Reputable products + proper steer tube expander plug (centered between top of stack and bottom of stem clamp) + deburr any sharp edges of other parts + carbon friction paste + correct tightening torque = as good or better than any alloy steer tube.
     
  12. wheeler

    wheeler Member

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    I have a set of carbon bars that are 5 years old, nicked up, been crashed ect...........if they were aluminum they would have been replaced three times.
     

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