Buncha Carbon Fiber Suckers....

Discussion in 'Cycling Equipment' started by IronDonut, May 17, 2005.

  1. Insight Driver

    Insight Driver New Member

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    http://www.velonews.com/media/easton_bolt.pdf

    You are ignornant and the qualities of carbon fiber, dude. You are spewing anger obviously. I think you are just like the wolf in the fable, calling the grapes sour because you can't have any.
     


  2. IronDonut

    IronDonut New Member

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    Yes you are right. Carbon fiber bolts would be much better than metal bolts.

    You're right I have two $6,000 Litespeeds (Niota and Vortex) because I can't affort a $1200 carbon bike.


     
  3. Adam-from-SLO

    Adam-from-SLO New Member

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    children.... children.... play nicely with your bicycles ;)
     
  4. FasterthanU

    FasterthanU New Member

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    The problems of induction....
     
  5. triguy98

    triguy98 New Member

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    Namely, the welding techniques and equipment weren't widely available for a long time. I saw an example of early Alum welding, wasn't pretty (still holding up fine 10 years later, tho) and I wouldnt pay for a frame welded like that. The modern gas shielded MIG machines are what allowed alum to take the place of steel.
     
  6. Insight Driver

    Insight Driver New Member

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    Obviously, obviously, didn't read the link..

    It's about how dumb wrenches don't follow torque specs and over-torque the shit out of their bikes. Try over-tightening some plumbing. You'll learn, first-hand, about a property of a material like copper when it's over-tightened.

    You have a good grasp of some material properties, but not enough knowledge to make intelligent decisions. You love titanium..woo hoo. It's 1/3 the strength of steel and it's modulus is one third of steel's also. Thing is, design is all about knowing the properties of the material you use and designing correctly for the application.

    Now, for the NTSB link about the plane, if you actually went deeper into the investigation you would have learned that the joint that failed was stronger than the metal joint that would have been there if they did not use carbon fiber. The real fault was over-reaction by the pilots and a control system that allowed it to happen. Basically they broke their plane by slamming the rudder up and down violently. It was not a weakness in the carbon fiber, as you are implying. You have cherry-picked what strengthens your case, only.
     
  7. IronDonut

    IronDonut New Member

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    I don't think there are a lot of MIG welded bike frames. Most of them are TIG.

     
  8. IronDonut

    IronDonut New Member

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    Steel is a great materials with two problems. It rusts and it's strength to weight ratio is poor. Finish is part of durability and a painted steel finish is no better than painted carbon or alum.

    About that plane... Thats what Airbus said regards their carbon fiber tail connection points. It's bullshit. Of course they are going to say whatever is required to dodge responsibility.

    Carbon fiber has an amasing strength to weight ratio in tension but in compression it's lousy. The messy thing about the real world is that structures are often subject to loads outside of their design intent. My problem with carbon fiber as a structural material is that it isn't as forgiving as metal when it comes to these random stresses. The carbon fiber mountain bike frames are a perfect example of the weaknesses of this material. Consider this; carbon fiber mountain bike frames have no weight advantage over their aluminum and titanium counterparts. Zero. In fact they are often at a weight disadvantage and it's because of carbon structures don't resist random loads well and metal does. So they have to overbuild the mountain bike frames to such a high degree that the carbon structures weigh more than their metal counterparts.

    Don't think I'm totally anti-carbon. I'm not. I'm in favor of using the right material for the job. I have carbon bars on my mountain bike because they are so much lighter than the metal ones. I have a carbon seatpost on my road bike to make it ride a little softer but a metal post on my mountain bike because the carbon posts aren't durable enough for that duty.

    The frames are all titanium for durability. It doesn't rust, there is no paint to scratch, it isn't soft like carbon and my shifter cables won't rub furrows into the frame and it doesn't fatigue like aluminum. And maybe most importantly I can run the bikes clean without gaudy decals and brand names all over my bike.



     
  9. artmichalek

    artmichalek New Member

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    Titanium doesn't fatigue?

    http://www.serotta.com/pages/current.html#Dec12
    http://www.cpsc.gov/cpscpub/prerel/prhtml05/05550.html
    http://www.bikepro.com/recalls/ericksonrecall.html
     
  10. SilentShifter

    SilentShifter New Member

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    I wish everyone would just get over themselves. Who gives a rats ass what someone else rides?

    You like steel? then ride steel
    You like CF? then ride CF
    You like aluminium? then ride aluminium
    You like Ti? then ride ti

    Why does everyone feel the need to trash other frame materials. Just like training routines, what works for one person may not work for another. Just ride what you want and leave other people be.

    Besides no one in here (or any other related thread) has been able to bring scientific laboratory controlled proof that one fame material is more comfortable, resilient, stronger, lighter, stiffer, etc. It has been nothing more than personal opinions.

    Just ride your bike its as simple as that.
     
  11. triguy98

    triguy98 New Member

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    And what did TIG evolve from? The gas shielding is what allows alum and titanium to be welded. Turn off your gas when welding them and try it. Can you say "splatter"? A steel bike can easily be welding MIG. Alum, you could. It's not the prettiest job, that's one of the benefits of TIG welding, nice clean welds.

    I think you mas produced frames are MIG welded. TIG is hand and labor intensive. MIG is faster and cheaper, hence the lower end frames having big welds. As you get into nicer higher end bikes, you get nicer looking welds.
     
  12. bikeguy

    bikeguy New Member

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    Hi,

    I would just like to say after buying a bike with a carbon fiber front fork
    and a wheel with a carbon profile (Zipp 404) I've noticed that these two
    transmit vibration considerably more than the completely aluminum bikes I've ridden on. When I go over a bump (a thumbnail sized rock will do) with a Zipp 404 it's a huge jolt, a jolt that is much less on the other alu front fork, alu wheeled bike I ride on. Seems to me that carbon fiber doesn't give, it doesn't flex, when you hit a bump it throws the bike up much more than alu. That said, the Zipp 404 is nice and light and the fork lightens up the bike too. I haven't had any problems with either even though I've hit a few potholes hard. I also had a alu rimmed Kysrium equipe, which disintegrated in the course of 9 months and maybe 6000 km (the rim was cracking in the middle). I wasn't impressed with that! Here's hoping the Zipp holds together a bit longer.. for the record I ride my bikes hard... I like to jack rabbit start and I usually ride pretty fast, I'm capable of a 38 km/hr 40 km TT, no aerobars.

    -Bikeguy
     
  13. Traffic Jammer

    Traffic Jammer New Member

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    Here here...I've just been reading this and if it's only Trek frames having these difficulties.... follow me here...... and they have been made oh so popular because of Lance. No comment on riding what your hero rides.

    Could it possibly be a manufacturing issue as it seems that these frames must be pretty darned popular these days? Rushing them out the door to hungry consumers?.....happens in every industry.
    :confused: :confused:
     
  14. friedmikey

    friedmikey New Member

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    A Zipp 404 has a 58mm rim profile - more than double the 25mm profile of your Equipes. I'd say it's a pretty safe assumption that it's going to tranmit more jolts. It would be interesting to hear your review after riding on a 58mm aluminum rim, if there even is such a thing.
     
  15. bikeguy

    bikeguy New Member

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    You've got a point about the rim depth - the longer the spokes I guess
    the more flex and even though the Zipp only has 18 spokes they are very tight and the wheel is stiff, but when I was riding with a standard rim depth alu wheel the front carbon fiber fork still transmits shock much more than the other bikes I've ridden with alu front forks. Not that it really matters, you do get used to the extra vibration. It just seems like carbon is way "harder" than alu, I feel like I'm rolling on round rock wheels and fork, which is fine if the road is smooth.

    Mountainbiking with carbon fiber? --- OW! No way!

    -Bikeguy
     
  16. mrowkoob

    mrowkoob New Member

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    Be aware of the fact that a low count spoked wheel (for example 18 spokes) is a lot less shock absorbant than a regular 32 spoke training wheel, the spokes act as the wheels shock absorbers. So a low spoked carbon wheel is less shock resistant than a multispoked aluminium wheel. Also unless the carbon wheel is made with shockabsorbation in mind there is no guarantee that it´s more absorbing than any other wheel out there. Primarily wheels are made to be as stiff as possible. Carbon frames can be made with shock absorbtion in mind but several are made to be as stiff and light as possible disregarding comfort.
     
  17. mitosis

    mitosis New Member

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    Spokes act as shock aborbers? I'm not sure an engineer would agree with you.
     
  18. mrowkoob

    mrowkoob New Member

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    Dampening would be the correct term, read up on it you´ll se
     
  19. artmichalek

    artmichalek New Member

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    Dampening isn't the right word. Damping isn't right in this case either. No energy is actually being absorbed. Your assessment of high and low spoke count wheels is right, but for the wrong reasons. On a 32 spoke wheel, you can make the rim light and flexible because the spokes support it evenly. Throw in tangential lacing and you get a wheel with a lot of radial compliance. Drop the spoke count and go to radial lacing, and the rim has to be a lot stiffer to be able to bridge the increased gap between the spokes. This is what makes for a less forgiving wheel.
     
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