Advertise on Bikeforums.net



User Tag List

Page 6 of 7 FirstFirst ... 4567 LastLast
Results 126 to 150 of 175
  1. #126
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by kickstart View Post
    Also scratches, chips, and dings that would be nothing more than cosmetic on metal can continue to degrade in composites if not addressed.
    this is a massive exaggeration. my crabon bikes are covered with scratches, chips, and dings and all of these are in the clear coat or surface weave.
    Last edited by spare_wheel; 08-10-14 at 08:58 PM.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  2. #127
    Senior Member
    Join Date
    Apr 2009
    Location
    New Rochelle, NY
    My Bikes
    too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
    Posts
    22,407
    Mentioned
    66 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by spare_wheel View Post
    this is a massive exaggeration. my crabon bikes are covered with scratches, chips, and dings and all of these are in the clear coat or surface weave.
    And of course, steel bikes never rust where the paint has been scratched through.
    FB
    Chain-L site

    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

  3. #128
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by spare_wheel View Post
    this is a massive exaggeration. my crabon bikes are covered with scratches, chips, and dings and all of these are in the clear coat or surface weave.
    Metals and composites are different materials with different strenghs, weaknesses, and characteristics, I don't see why understanding and recognizing the differences would be an exaggeration. If there are no differences, why not just use the cheapest materials?

  4. #129
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FBinNY View Post
    And of course, steel bikes never rust where the paint has been scratched through.
    Yes they do, but considering this is the safety sub forum, I question the wisdom of refuting the nonsense of the OP in a way that gives the impression that composites can be treated with the same abuse and neglect as metals.

  5. #130
    Senior Member
    Join Date
    Apr 2009
    Location
    New Rochelle, NY
    My Bikes
    too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
    Posts
    22,407
    Mentioned
    66 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by kickstart View Post
    Yes they do, but considering this is the safety sub forum, I question the wisdom of refuting the nonsense of the OP in a way that gives the impression that composites can be treated with the same abuse and neglect as metals.
    Sorry, I refuse to use a tongue in cheek emoticon (if one even exists) and figured the intent was obvious.

    But I think (agree?) that this entire thread is nonsense based on nonsense, so I just put a stick in and stir once in a while to see what comes up from the bottom.
    FB
    Chain-L site

    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

  6. #131
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FBinNY View Post
    Sorry, I refuse to use a tongue in cheek emoticon (if one even exists) and figured the intent was obvious.

    But I think (agree?) that this entire thread is nonsense based on nonsense, so I just put a stick in and stir once in a while to see what comes up from the bottom.
    Right over my head, no need to apologize.

    I agree the thread is nonsense as presented, but it may still be useful in that it may get folks to learn more about their composite bike than their salesman chose to tell them. It could save someone from a preventable injury.

  7. #132
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by kickstart View Post
    Yes they do, but considering this is the safety sub forum, I question the wisdom of refuting the nonsense of the OP in a way that gives the impression that composites can be treated with the same abuse and neglect as metals.
    a valid point. i definitely believe a carbon bike that has had a significant crash should always be inspected by a professional.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  8. #133
    Senior Member
    Join Date
    Apr 2009
    Location
    New Rochelle, NY
    My Bikes
    too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
    Posts
    22,407
    Mentioned
    66 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by spare_wheel View Post
    a valid point. i definitely believe a carbon bike that has had a significant crash should always be inspected by a professional.
    And how many professionals are there capable of doing a proper analysis?.
    FB
    Chain-L site

    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

  9. #134
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    >And how many professionals are there capable of doing a proper analysis?.

    More than you'd think, FBinNY. For example, in my neck of the woods:

    Carbon Fiber Repair | Ruckus Composites
    Spyder Composites | Carbon Fiber Bike Repair


    In your neck of the woods:

    Testimonials | Brooklyn Carbon Bicycle Repair
    About :Carbon Phoenix Repairs

    etc.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  10. #135
    Senior Member
    Join Date
    Apr 2009
    Location
    New Rochelle, NY
    My Bikes
    too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
    Posts
    22,407
    Mentioned
    66 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by spare_wheel View Post
    >And how many professionals are there capable of doing a proper analysis?.

    More than you'd think, .
    I think you might have missed my point. While there are a number of places capable of repairing a carbon frame with visible damage. There are very few capable of assessing the safety of a crashed frame that has no visible damage. There's no debate about visible damage, the concerns voiced against carbon are related to invisible damage.
    FB
    Chain-L site

    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

    “One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

  11. #136
    Senior Member squirtdad's Avatar
    Join Date
    Jul 2006
    Location
    San Jose (Willow Glen) Ca
    My Bikes
    '89 Miyata 1400, '82 nishiski (current utilty/commuter project)
    Posts
    3,354
    Mentioned
    9 Post(s)
    Tagged
    0 Thread(s)
    Another concern related to long term safety of carbon frames is impact of aging.

    From looking around there is a level of concern from "what are you talking about, it is no big deal" to "ticking time bomb of old carbon frames" (that is a quote

    Who knows where the truth is, but the point is that it is an unknown and is probably highly variable due to specific materials, build process, design, how and how and where any one bike is stored and cared for.

    so the real question is how to evaluate an older bike?

    ymmv but fpersonally the only way I will buy a carbon bike is with a warranty....... (not likely to happen as a prefer the look of classic steel (and don't get me started on the uglyness that is threadless stems)
    '82 Nishiski commuter/utility
    '83 Torpado Super Strada ... cafe commuter
    '89 Miyata 1400
    Soma rush Fixie
    '78 Univega gran turismo (son's Fixie/SS)
    06 Haro x3 (son's bmx)
    Electra cruiser (wife's bike)

    looking for: De Rosa 58cm ELOS frame and fork internal cable routing

  12. #137
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FBinNY View Post
    the concerns voiced against carbon are related to invisible damage.
    Anecdote. I should also mention that the only sudden failures I've experienced have been with metal frames...but this is also an anecdote.

    And let me quote:

    With over 26 years of experience inspecting and building composite structures, our Level II and III certified technicians have the capability to detect and identify most unseen impact damage by using various NDT methods. By using Ultrasonic Inspection and Radiography (x-ray), we have developed specific propietary techniques to detect the smallest inconsistency within the structure giving us the confidence that the damaged area will be completely repaired. As Lennard Zinn said; “why tempt fate”.
    Last edited by spare_wheel; 08-12-14 at 02:01 PM.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  13. #138
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by squirtdad View Post
    Another concern related to long term safety of carbon frames is impact of aging.
    Link please.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  14. #139
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by squirtdad View Post
    so the real question is how to evaluate an older bike?
    I've tried to buy older carbon bikes but I've always been outbid. Personally, I'd have no problem riding a used carbon frame without obvious damage.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  15. #140
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by spare_wheel View Post
    Link please.
    I can't provide any links, but from my limited experience in working with composites it can be a legitimate concern depending on many factors. I wouldn't be overly concerned unless there are obvious signs of abuser or neglect.
    My favorite bike is my 1935 Raleigh sport, its obviously had a hard life but I haven't the slightest doubt about its structural integraty, I don't think I would trust an 80 year old composite bike, but as I won't be around to find out I won't worry about it.

  16. #141
    Senior Member rydabent's Avatar
    Join Date
    Apr 2010
    Location
    Lincoln Ne
    My Bikes
    RANS Stratus TerraTrike Cruiser
    Posts
    4,148
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    kick start

    Good point. There are many examples of metal bikes back before 1900. Kinda makes you wonder what todays fantastic plastic bikes will look like in 100 years.

  17. #142
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by rydabent View Post
    kick start

    Good point. There are many examples of metal bikes back before 1900. Kinda makes you wonder what todays fantastic plastic bikes will look like in 100 years.
    It's important to remember those old bikes were built to last a lifetime, today's composite bikes are built to take advantage of the latest materials. Some plastics such as Bakelite have stood the test of time, but that's not a priority with today's builders, and bicycles seem to be subject to the same planned obsolescence as many other products.

  18. #143
    Senior Member howsteepisit's Avatar
    Join Date
    Oct 2005
    Location
    Eugene, OR
    My Bikes
    Mecian
    Posts
    2,971
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Can anyone provide any substantive evidence of carbon fiber bicycles aging in any dangerous manner? Or Aluminum, of titaniaum, Or Bamboo?

    My sense is its more unjustified handwringing over anything new.
    Recycle, Reclaim, Reuse and Repair
    The 4 Rs to save the planet

    "Toes"

  19. #144
    Senior Member meanwhile's Avatar
    Join Date
    Jun 2008
    Posts
    4,033
    Mentioned
    7 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Pibber View Post
    This one time, an older woman called my SR a "crackanfail", an allusion, I imagine, to the supposed weakness of aluminum. .
    Nope. It's an allusion to C'dales diasterous period of making bikes with frames that did crack and fail - they used very large diameter tubing with super thin walls. Alu GTs and Kleins were alu too, but no one picked on them because they were crack n' failing.

  20. #145
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by howsteepisit View Post
    Can anyone provide any substantive evidence of carbon fiber bicycles aging in any dangerous manner? Or Aluminum, of titaniaum, Or Bamboo?

    My sense is its more unjustified handwringing over anything new.
    Composites aren't new and they do degrade with age, that's a fact. How today's composite bikes will age is merely speculation, and its unlikely many of us will be around when it is a problem.
    All materials "age", the real question is if they will be structurally sound for their intend use and lifespan.
    I don't see the harm in being aware of the differences and possible issues.

  21. #146
    Senior Member howsteepisit's Avatar
    Join Date
    Oct 2005
    Location
    Eugene, OR
    My Bikes
    Mecian
    Posts
    2,971
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    If its a fact that composites degrade with age, then there must be an engineering analysis of how much, how fast, and to what degree that decomposition occurs. If you know of such study then post a link if available, otherwise I suspect you are posting internet facts, which may or may not have a basis in reality.

    Any just to be clear, I do not own a CF bike, nor likely will I. I prefer the look and ride of classic level top tube steel bikes. But that preference does not lead me to speculate that CF bike are going to catastrophically fail at some unknown time in the future due to unqantified aging of the construction material, based on facts gleaned fro unspecified internet sources.
    Recycle, Reclaim, Reuse and Repair
    The 4 Rs to save the planet

    "Toes"

  22. #147
    Senior Member
    Join Date
    Jan 2011
    Location
    pdx
    My Bikes
    2007 carpe diem frame custom build, trek 7.9 frame custom build, custom built chinese carbon fiber road bike, shopping bike
    Posts
    3,297
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by howsteepisit View Post
    If its a fact that composites degrade with age, then there must be an engineering analysis of how much, how fast, and to what degree that decomposition occurs.
    Thanks for asking again and again. I'm interested in any response, if one emerges.
    This is why motorists hate us, and why I've given up riding on the road...You should be ashamed yourself, and you should be reviled by cyclists everywhere.

  23. #148
    Senior Member
    Join Date
    Dec 2013
    Location
    antipodes
    Posts
    138
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by howsteepisit View Post
    If its a fact that composites degrade with age, then there must be an engineering analysis of how much, how fast, and to what degree that decomposition occurs. If you know of such study then post a link if available, otherwise I suspect you are posting internet facts, which may or may not have a basis in reality.
    Quote Originally Posted by spare_wheel View Post
    Thanks for asking again and again. I'm interested in any response, if one emerges.
    These would exist for sure. The accessible ones would be university-based material testing non-specific to cycling, but the trick would be knowing the precise carbon and epoxy used in the frames in which you are interested in order to find the right study. Manufacturers don't really realise that information as far as I know. The bigger manufacturers like Trek and Giant probably do their own inhouse or out-sourced materials testing specific to cycling stresses, but these would be secret no doubt. Just like so many other industries, they would not have any interest in making, or releasing any information concerning, a products ability to last any longer than their certification standard or warranted lifespan.

    However, I am guessing there might testing for certification standards like there are in furniture. Basically if a chair needs to be approved for mass sale in a lot of places a sample has to be provided to an organisation, like a university, who puts the chair on a machine which simulates somebody sitting down and getting up a thousand times or more until it breaks, or doesn't break. They do it for cars too, they must do this for bicycles and I'd be interested in finding out more about it. It doesn't necessarily give any information as to how a material will degrade over time (decomposition from use + weather + ?), but it would indicate which frames are generally tougher. Potentially the information as to how well a frame does in the test is publicly available. Or not.

  24. #149
    Senior Member
    Join Date
    Feb 2014
    Location
    Kent Wa.
    My Bikes
    1935 Raleigh Sports X,1970 Robin Hood, Flying Pigeon, Ross hi-tec, Schwinn Phantom
    Posts
    1,241
    Mentioned
    6 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by howsteepisit View Post
    If its a fact that composites degrade with age, then there must be an engineering analysis of how much, how fast, and to what degree that decomposition occurs. If you know of such study then post a link if available, otherwise I suspect you are posting internet facts, which may or may not have a basis in reality.

    Any just to be clear, I do not own a CF bike, nor likely will I. I prefer the look and ride of classic level top tube steel bikes. But that preference does not lead me to speculate that CF bike are going to catastrophically fail at some unknown time in the future due to unqantified aging of the construction material, based on facts gleaned fro unspecified internet sources.
    I'm not an engineer, and I haven't researched the subject other than some how-to and material safety information, its mostly what I picked up first hand maintaining composite boats while in the coast guard, working for viking yachts building composite boats, building a wood/epoxy composite sea kayak for my own gratification, and some very limited exposure to the aerospace industry. What I can say for sure, a lot of time thought and effort is put into protecting composites from the effects of UV exposure, temperature extremes, moisture, impact, and vibration depending on the materials and how they are used.

    I have a very healthy respect for the usefulness of composites, including its use for bicycles, but also know that composites, like all materials, have limitations. I just don't understand why recognizing the limitations of a good, useful material, whatever it may be, should be taken as a condemnation of it.

    Seems to me those who condemn CF bikes or say they are without fault are trying to sell something.

  25. #150
    Senior Member howsteepisit's Avatar
    Join Date
    Oct 2005
    Location
    Eugene, OR
    My Bikes
    Mecian
    Posts
    2,971
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Because you are not able to quantify or even substantiate the limitations on CF bicycle frames. Yet you said that in fact the composites degrade with age, without knowing if any degradation was substantive or even measurable. This puts you in the category of an internet expert....blowing wind. I did a few hours research today and did find a Masters Thesis that attempted to quantify the amount of degradation in general, seems that in that case it was limited to 6% under accelerated aging conditions of 750 hours. Additional aging up to 1500 hours did not result in additional decrease in strength. However this was not specific to cycle construction material. Take that for what its worth, I din't even bother to keep the link.

    I don't believe a 6% decrease in tubing strength would be significant to a CF bicycle frame. I also reviewed an article by Lenard Zinn in an old velo news where he queried CF fork manufacturers about the service life of CF forks, they seemed to generally say no, but their responses were mostly concerned with vibration cycles not UV weakening. And immersion/condensation testing of composites which are used for marine materials don'e seem to apply to a bicycle that is not ridden underwater.
    Recycle, Reclaim, Reuse and Repair
    The 4 Rs to save the planet

    "Toes"

Page 6 of 7 FirstFirst ... 4567 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •