A chastening reminder of the risks of carbon

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Comments

  • adamfo
    adamfo Posts: 763
    bianchimoon wrote:
    my aftermarket carbon bars have cracks where the clamp was overtightened before I bought a torque wrench, have been keeping a careful eye on how the carbons behaving/deteriorating for last 18 months and doesn't seem to be getting any worse even given the state of the roads around here.

    What sort of torque figure should be used ?

    I recently bought some Easton SL70 carbon bars. Sign up to wiggle's newsletter and they are £85. Not exactly expensive. Like many recent designs coming out they use UD carbon with a matte finish, not visible weave 3k.
    Some will disagree but I think UD is a more suitable and stronger material.

    http://www.wiggle.co.uk/easton-ec70-sl-road-handlebar/
  • bianchimoon
    bianchimoon Posts: 3,942
    adamfo wrote:
    bianchimoon wrote:
    my aftermarket carbon bars have cracks where the clamp was overtightened before I bought a torque wrench, have been keeping a careful eye on how the carbons behaving/deteriorating for last 18 months and doesn't seem to be getting any worse even given the state of the roads around here.

    What sort of torque figure should be used ?

    I recently bought some Easton SL70 carbon bars. Sign up to wiggle's newsletter and they are £85. Not exactly expensive. Like many recent designs coming out they use UD carbon with a matte finish, not visible weave 3k.
    Some will disagree but I think UD is a more suitable and stronger material.

    http://www.wiggle.co.uk/easton-ec70-sl-road-handlebar/
    5Nm is the recommendation for carbon components
    All lies and jest..still a man hears what he wants to hear and disregards the rest....
  • Coach H
    Coach H Posts: 1,092
    cougie wrote:
    You are riding round on cracked bars ? It's reassuring to know they've lasted 18 months or so - but you are a braver man than me ! Any plans to replace them at all ?

    I am not riding on it, but I have a cracked carbon seatpost sitting on my desk (just heard it go with no warning and cracked 1/3 of circumference, replaced on warranty). Still "feels" solid and been regularly using it as a hammer for wall tacks with no issues to date! :shock:
    Coach H. (Dont ask me for training advice - 'It's not about the bike')
  • lawrences
    lawrences Posts: 1,011
    adamfo wrote:
    bianchimoon wrote:
    my aftermarket carbon bars have cracks where the clamp was overtightened before I bought a torque wrench, have been keeping a careful eye on how the carbons behaving/deteriorating for last 18 months and doesn't seem to be getting any worse even given the state of the roads around here.

    What sort of torque figure should be used ?

    I recently bought some Easton SL70 carbon bars. Sign up to wiggle's newsletter and they are £85. Not exactly expensive. Like many recent designs coming out they use UD carbon with a matte finish, not visible weave 3k.
    Some will disagree but I think UD is a more suitable and stronger material.

    http://www.wiggle.co.uk/easton-ec70-sl-road-handlebar/

    I agree with you that UD is probably stronger though I have no scientific data I'm just guessing. I do know that alot of the time when a carbon component has a weave finish it's just a cosmetic top layer.
  • Barbarossa
    Barbarossa Posts: 248
    UD is stronger - in one direction only (hence the name). A handlebar is subject to bending and torsion. The optimum layup is going to be a mixture of 0 degree and +/-45 degree fibres.
  • dennisn
    dennisn Posts: 10,601
    964Cup wrote:

    Now I'm thinking hard about replacing the SLC2's with alloy bars as well.

    If I post a picture of a broken ALLOY bar, then what would you buy?
    Your broken / cracked bar proves absolutely nothing about carbon bars except that you happen to own a broken one. :wink:
  • Gary D
    Gary D Posts: 431
    It's difficult to assess without seeing the actual bars, but it may just be that it is the outer decorative layer of the bars that is damaged. Much like frames, the outer "woven" layer is purely for decorative purposes.

    I have got a set of FSA Wing Bars and I fitted a different stem and cap for a short period so I could use some tri-bars. Although I used a torque wrench when fitting them, when I changed the stem back, to my horror the bars appeared to have "cracked" around where the stem clamped - exactly like your bars look. I thought the bars were scrap :cry: :evil:

    However, I had them looked at and tested at a certified composites test facility and they confirmed that it was cosmetic damage only to the laquer and outer layer and that the bars would be safe.

    (However, I haven't put them back on the bike yet and tried them :oops: )

    Gary.
    Fungus The Muffin MAn wrote:
    Oh and I feel like I've been raped by an Orangutan :shock: And I've got legs like Girders :lol:
  • Barbarossa
    Barbarossa Posts: 248
    Amongst the people I cycle with, I have seen 2 potentially serious failures (luckily neither lived up to their potential). One wa a broken handlebar in a CX race, the other was a failure between the top tube and head tube. Both in aluminium parts.
  • Alitogata
    Alitogata Posts: 148
    dennisn wrote:
    964Cup wrote:

    Now I'm thinking hard about replacing the SLC2's with alloy bars as well.

    If I post a picture of a broken ALLOY bar, then what would you buy?
    Your broken / cracked bar proves absolutely nothing about carbon bars except that you happen to own a broken one. :wink:

    I have heard more cases about broken carbon parts than aluminum.
  • lawrences
    lawrences Posts: 1,011
    Barbarossa wrote:
    UD is stronger - in one direction only (hence the name). A handlebar is subject to bending and torsion. The optimum layup is going to be a mixture of 0 degree and +/-45 degree fibres.

    It's called UD (unidirectional fibres) referring to the microscopic fibre layup, the name has nothing to do with it's strength charecteristics.
  • dennisn
    dennisn Posts: 10,601
    Alitogata wrote:
    dennisn wrote:
    964Cup wrote:

    Now I'm thinking hard about replacing the SLC2's with alloy bars as well.

    If I post a picture of a broken ALLOY bar, then what would you buy?
    Your broken / cracked bar proves absolutely nothing about carbon bars except that you happen to own a broken one. :wink:

    I have heard more cases about broken carbon parts than aluminum.

    I'm thinking that many of the cases that you've heard about are people chiming in with scratches on their new carbon frames, bars, whatever, and wondering if they should throw them away. Many, many of the posts on BR are from people who see a simple scratch, on carbon, as a death sentence crack for that new mega dollar part. Not sure where this paranoia comes from but it appears to be very widespread among carbon owners. I also don't quite understand why people would buy something that, when it gets scratched(and it will), would cause them all that worry.
  • MountainMonster
    MountainMonster Posts: 7,423
    dennisn wrote:
    Alitogata wrote:
    dennisn wrote:
    964Cup wrote:

    Now I'm thinking hard about replacing the SLC2's with alloy bars as well.

    If I post a picture of a broken ALLOY bar, then what would you buy?
    Your broken / cracked bar proves absolutely nothing about carbon bars except that you happen to own a broken one. :wink:

    I have heard more cases about broken carbon parts than aluminum.

    I'm thinking that many of the cases that you've heard about are people chiming in with scratches on their new carbon frames, bars, whatever, and wondering if they should throw them away. Many, many of the posts on BR are from people who see a simple scratch, on carbon, as a death sentence crack for that new mega dollar part. Not sure where this paranoia comes from but it appears to be very widespread among carbon owners. I also don't quite understand why people would buy something that, when it gets scratched(and it will), would cause them all that worry.

    That's exactly it though, they don't buy parts that, when it gets scratched, will fail. They just THINK they will.

    This happens with all new materials, it takes decades for people to change their perception of the material and stop worrying about it so much. People see failures and assume the material is crap.
    My London Road
  • bigmat
    bigmat Posts: 5,134
    People have this issue with carbon bars, but then are happy to ride carbon forks. This is almost universal, on steel, titanium and aluminium bikes. I just don't get it. Both my carbon seatposts have splits to the lacquer down the back - overtightened seatpost clamp - both have gone on to cover thousands of miles without issue. I have snapped carbon bars in crashes but then I have bent aluminium bars beyond repair in similar crashes.
    http://www.flickr.com/photos/41991871@N ... otostream/
  • dennisn
    dennisn Posts: 10,601
    MountainMonster wrote:
    dennisn wrote:
    Alitogata wrote:
    dennisn wrote:
    964Cup wrote:

    Now I'm thinking hard about replacing the SLC2's with alloy bars as well.

    If I post a picture of a broken ALLOY bar, then what would you buy?
    Your broken / cracked bar proves absolutely nothing about carbon bars except that you happen to own a broken one. :wink:

    I have heard more cases about broken carbon parts than aluminum.

    I'm thinking that many of the cases that you've heard about are people chiming in with scratches on their new carbon frames, bars, whatever, and wondering if they should throw them away. Many, many of the posts on BR are from people who see a simple scratch, on carbon, as a death sentence crack for that new mega dollar part. Not sure where this paranoia comes from but it appears to be very widespread among carbon owners. I also don't quite understand why people would buy something that, when it gets scratched(and it will), would cause them all that worry.

    That's exactly it though, they don't buy parts that, when it gets scratched, will fail. They just THINK they will.

    This happens with all new materials, it takes decades for people to change their perception of the material and stop worrying about it so much. People see failures and assume the material is crap.

    Good points.
  • Mikey23
    Mikey23 Posts: 5,306
    Which threads such as this don't help to dispel...
  • nferrar
    nferrar Posts: 2,511
    Despite being a big fan of carbon I use alloy bars on all my MTBs and road bikes, they are much more likely to get impact damage than other parts, there's very little benefit from carbon version and I get peace of mind (I'm well aware alloy bars can fail suddenly and catastrophically so this may just be me being unreasonable :p )
  • dennisn
    dennisn Posts: 10,601
    nferrar wrote:
    Despite being a big fan of carbon I use alloy bars on all my MTBs and road bikes, they are much more likely to get impact damage than other parts, there's very little benefit from carbon version and I get peace of mind (I'm well aware alloy bars can fail suddenly and catastrophically so this may just be me being unreasonable :p )

    I don't see it as being "unreasonable". I call it saving some money.
  • dennisn
    dennisn Posts: 10,601
    Mikey23 wrote:
    Which threads such as this don't help to dispel...

    On the flip side of the, so called, dangers of carbon, I recently purchased a Ritchey WCS bar because it had the shape i like and a flat top surface for a bit more hand comfort. As an added bonus I found that the little rear view mirror that I mount on the bar end had much less vibration, and therefore much more clarity, than when used on aluminum bars. On aluminum bars the mirror seemed almost useless.
  • owenlars
    owenlars Posts: 719
    I have had two ally bars fail on me, luckily the first time as I came to rest outside my gate the left hand side sheared off, the other time the same side went but slowly and gracefully allowing me to gently ride home two or three miles one handed. So yes ally does fail and both these bars were the same brand. I don't use them anymore.
  • Alitogata
    Alitogata Posts: 148
    dennisn wrote:

    I'm thinking that many of the cases that you've heard about are people chiming in with scratches on their new carbon frames, bars, whatever, and wondering if they should throw them away. Many, many of the posts on BR are from people who see a simple scratch, on carbon, as a death sentence crack for that new mega dollar part. Not sure where this paranoia comes from but it appears to be very widespread among carbon owners. I also don't quite understand why people would buy something that, when it gets scratched(and it will), would cause them all that worry.

    Even if some exaggerate about how delicate is carbon, I think, ( and you agree I suppose) that all this exaggeration comes from somewhere. And it seems that this comes from the fact that lot of carbon frames and parts had damages or broke, at least, ( I don't say that carbon as material is not good at all) in the past. Whatever is the reason thought, I hear more often about broken carbon frames and parts, true damages not just scratches, than broken aluminum parts.
    Anyway.. I personally prefer for my handlebars, seat post and stems materials that have more possibilities to bend than brake. But this is my personal choice and I don't want to say or advice other people to use something they like. :)
  • andrewjoseph
    andrewjoseph Posts: 2,165
    Good article in October issue of 'cyclist' mag.
    --
    Burls Ti Tourer for Tarmac, Saracen aluminium full suss for trails
  • rickeverett
    rickeverett Posts: 988
    Carbon bars are a waist of money imo and run a slightly higher risk.

    The weight saving is so small you could probably loose it with a good fart.

    for bars I would always stick with alloy.
  • frisbee
    frisbee Posts: 691
    I've only seen broken steel frames, including a chain hanger nubbin that pinged off mine when I was just riding along...

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