Welcome guest, is this your first visit? Click the "Create Account" button now to join.

To disable ads, please log-in.

Shop at TeamEstrogen.com for women's cycling apparel.

Page 1 of 2 12 LastLast
Results 1 to 15 of 20
  1. #1
    Join Date
    May 2012
    Location
    central NY
    Posts
    407

    What are the disadvantages to a carbon frame?

    To disable ads, please log-in.

    Or, in other words, do I need a carbon bike? I never really considered carbon, but I've just seen two bikes that have me thinking. I know they're light and smooth. Are they strong, too? I have this perception of hitting a pothole and having the bike shatter. That's not really likely, is it?

    Most of my riding is on the road. Some of the roads around here are kind of rough, and there's one service road that has areas of broken pavement. There's also a gate, and when it's down, we have to ride off-road on a well packed path to go around it.

    The LBS near me has a used Madone for sale that I plan to test ride tomorrow. It's a few years old, triple crank, 105 components. Anything in particular I should look for?

  2. #2
    Join Date
    Dec 2005
    Location
    WA State
    Posts
    4,391
    they make airplanes out of carbon fiber…
    "Sharing the road means getting along, not getting ahead" - 1994 Washington State Driver's Guide

    visit my flickr stream http://flic.kr/ps/MMu5N

  3. #3
    Join Date
    Sep 2007
    Location
    Uncanny Valley
    Posts
    14,645
    Not sure that's relevant since an airplane, once crashed, is NOT going to be flown again ...

    My frame survived my faceplant and more than one tip-over, including one that was hard enough to strip the threads on the derailleur hanger. It's been inspected more than once, basically because of its history I let a pro look at it any time I see a new paint chip, and it's fine.

    If you're looking at a used frame, look very closely for any chipped paint, and especially for any linear cracks in the paint. I'd be confident buying through a LBS, simply because they've got liability problems if they sell you a cracked frame. If it makes you feel more comfortable, you might ask them if the former owner has given them permission to let you have their contact info so you could ask them about the frame's history, but I wouldn't worry if they don't.

    Rough road like chip-seal or gravel is when carbon really shines.
    Speed comes from what you put behind you. - Judi Ketteler

  4. #4
    Join Date
    Sep 2008
    Location
    Ohio
    Posts
    164
    I bought a used Ruby and can vouch for the strength of the carbon frame. I am not a lightweight and don't baby my rides. I got mild whiplash last summer when I was forced to swerve from a truck side swiping me and hit a pothole, hard. Thought the fork would snap, but it held. Now there is a gash below the head tube, but the bike shop deemed it cosmetic, no carbon damage. I will add that I usually ride it with 700x28 tires to help smooth out the ride. I will admit to being worried about the gash though, despite the shop's reassurance.

    I find, for me, with the frame being stiff, the ride can be fatiguing with vibrations on long rides. Maybe my experience differs from Oakleaf because of my size, the difference in our frame geometry, or even tire pressure. I don't know. There are variables to consider. I hope your test ride gives you some answers. The tradeoff is, the Ruby is light. I do have a quality steel touring bike that is very smooth and the ride is much more comfortable. But, the bike is heavier, but not by much.

  5. #5
    Join Date
    May 2012
    Location
    central NY
    Posts
    407
    Thanks for the info. I was only kind of kidding about the pothole danger. It's just I hear that it's smooth, but stiff. My engineering brain is trying to get around that. So the vibrations get absorbed by the individual fibers?

    For me, now, fit is the ultimate concern, so I have 6 bikes on my list to try out this week. Two of them just happen to be carbon, and if there turns out to be a toss-up, I'm just wondering if the carbon is worth it.

    The snow has finally melted...

  6. #6
    Join Date
    May 2008
    Location
    northern Virginia
    Posts
    5,845
    I don't worry about my carbon frame while I'm riding. I do feel I have to be overly careful with it when I'm not riding it, after spending hundreds of dollars to have a mystery crack repaired about a year after I got it. It is my first and last carbon bicycle.

    - Gray Trek Madone 4.7 road bike, mystery crack in top tube repaired by Calfee, Bontrager Affinity RXL saddle
    - Red Trek 6000 mountain bike, Bontrager Evoke WSD saddle

    Gone but not forgotten:
    - Silver Trek 2000 road bike
    - Two awesome and worn out Juliana saddles

  7. #7
    Join Date
    Feb 2005
    Location
    Concord, MA
    Posts
    13,129
    I would say it is worth it. I am on my 3d carbon bike and the first 2 had various falls, minor dings, put in the back of my car with no ill effects. Do you need carbon? No. But it feels really nice. My first road bike was aluminum and that was the worst for me.
    I do also have a titanium bike, which is smooth in a different way. More expensive than carbon, though.
    2015 Trek Silque SSL
    Specialized Oura

    2011 Guru Praemio
    Specialized Oura

  8. #8
    Join Date
    Dec 2005
    Location
    WA State
    Posts
    4,391
    Quote Originally Posted by OakLeaf View Post
    Not sure that's relevant since an airplane, once crashed, is NOT going to be flown again ...
    Oh you think so…. sure if it's catastrophic and all that's left are little pieces, but it's actually kind of scary some of the airplanes that they've refit and reflown…… There's an amazing video of a plane that lands so hard the tail falls off…. granted it was a test plane and the hard landing was kind of intentional (it ended up being harder than they really meant), but apparently the plane had a new tail fit and went on to have a long life as a test plane - eek!
    "Sharing the road means getting along, not getting ahead" - 1994 Washington State Driver's Guide

    visit my flickr stream http://flic.kr/ps/MMu5N

  9. #9
    Join Date
    May 2012
    Location
    central NY
    Posts
    407
    So since yesterday I've ridden two carbon bikes, different brands, and I think I've found a little problem. The top tubes on both were wider than on the similar aluminum models. My inner thighs kept rubbing against the frame. Admittedly. I don't have the thinnest thighs, but they're not huge, either and I couldn't ignore it. But they were both really nice rides.

  10. #10
    Join Date
    May 2008
    Location
    northern Virginia
    Posts
    5,845
    Quote Originally Posted by Eden View Post
    Oh you think so…. sure if it's catastrophic and all that's left are little pieces, but it's actually kind of scary some of the airplanes that they've refit and reflown…… There's an amazing video of a plane that lands so hard the tail falls off…. granted it was a test plane and the hard landing was kind of intentional (it ended up being harder than they really meant), but apparently the plane had a new tail fit and went on to have a long life as a test plane - eek!
    F1 cars are carbon fiber, and I'm pretty sure the chassis (what is the plural of that word?) are repaired when needed. The thinner parts like wings tend to shatter into shards so they get replaced. The safety standards for the cars are strict (and amazingly effective) so repaired carbon would not be allowed if it didn't meet the structural requirements.

    However I don't think my mass-produced bike is as high a quality material as an F1 car.

    - Gray Trek Madone 4.7 road bike, mystery crack in top tube repaired by Calfee, Bontrager Affinity RXL saddle
    - Red Trek 6000 mountain bike, Bontrager Evoke WSD saddle

    Gone but not forgotten:
    - Silver Trek 2000 road bike
    - Two awesome and worn out Juliana saddles

  11. #11
    Join Date
    Jun 2010
    Posts
    6,465
    Aircraft tend to have carbon parts mixed with whatever the remainder of the fuselage is made from. So, not 100% carbon. In fact, F-16's had less than 2% carbon (mainly the tail, and some on the nose? Can't remember about the nose, but I think that was it), F-18's and AV8B's had more, maybe 13%, can't remember; a lot was in the wings. It's been awhile!

    The newer jets probably have more, but not necessarily. No idea what that does to the durability. Carbon is lighter and stronger, but when it fails, does it ever fail!

    When aircraft crash and the carbon-fiber burns, particulate in the air is quite hazardous to breathing, and the pieces can get lodged in the lungs. I would hope that is not relevant to bicycles.
    Last edited by Muirenn; 04-14-2015 at 10:31 AM.
    So long as the wheels are still turning, life is good.

    Battswebb

    Pinarello Quattro~CAADX~ Zurich Lemond
    Specialized Romin Saddles

    Surly Krampus!

  12. #12
    Join Date
    Dec 2005
    Location
    WA State
    Posts
    4,391
    Quote Originally Posted by Muirenn View Post
    When aircraft crash and the carbon-fiber burns... I would hope that is not relevant to bicycles.
    lol.. only in the movies (thinking of the myth busters episode that showed how really hard it is to crash a car and have it catch fire or even more crazy, explode- but how it seems *every* crash in the movies results in an eye catching, but completely fallacious fireball)

    I'd make a guess the carbon fiber on an F1 car isn't structural, but just an aerodynamic shell, so I can't imagine repairing it wouldn't be a safety issue, unless the repair could possible shatter or tear off under the pressure of the wind? I have seen carbon fiber bike frames fail - but as far as I know all the failures have happened during or after a crash which damaged the carbon. For sure care needs to be taken, as damage done may not be readily visible, but I wouldn't expect normal knocks to have any affect - there are carbon mt. bikes, so a pothole shouldn't pose a problem. I've also seen aluminum, ti and steel all fail too, nothing is invulnerable.
    Last edited by Eden; 04-14-2015 at 10:37 AM.
    "Sharing the road means getting along, not getting ahead" - 1994 Washington State Driver's Guide

    visit my flickr stream http://flic.kr/ps/MMu5N

  13. #13
    Join Date
    Sep 2007
    Location
    Uncanny Valley
    Posts
    14,645
    Potentially slightly more relevant to this discussion is Ducati's failed experiment with a carbon fiber frame. The bike was famously too stiff and wouldn't steer. They've gone back to aluminum for 2015, but are keeping the carbon fiber swingarm.

    The carbon is also structural in the cars. They can get away with it because of the much, much, much larger tire contact patches.
    Speed comes from what you put behind you. - Judi Ketteler

  14. #14
    Join Date
    Jun 2010
    Posts
    6,465
    Quote Originally Posted by OakLeaf View Post
    much, much, much larger tire contact patches.
    You mean that tires contact the road in a much greater surface area than a bicycle tire?

    Actually,...English, please?
    So long as the wheels are still turning, life is good.

    Battswebb

    Pinarello Quattro~CAADX~ Zurich Lemond
    Specialized Romin Saddles

    Surly Krampus!

  15. #15
    Join Date
    May 2008
    Location
    northern Virginia
    Posts
    5,845
    Quote Originally Posted by Muirenn View Post
    You mean that tires contact the road in a much greater surface area than a bicycle tire?

    Actually,...English, please?
    There's a good picture of the cars here.

    http://www.formula1.com/content/fom-...ed-podium.html

    I think there must be something more solid in the part above/behind the driver's heads, which is there for safety reasons. I've seen the driver walk away unhurt after his car flipped upside down and then bounce rightside up again. Whatever is in there, the car did not break apart from the impacts.

    Anyway, as I said before, they have different requirements and budgets in mind when they make the carbon for these cars vs. mass-produced bike frames. I can't find the link to it, but I recall BikesnobNYC writing about his carbon road bike cracking pretty easily, from hitting against a lamppost or something similar.

    - Gray Trek Madone 4.7 road bike, mystery crack in top tube repaired by Calfee, Bontrager Affinity RXL saddle
    - Red Trek 6000 mountain bike, Bontrager Evoke WSD saddle

    Gone but not forgotten:
    - Silver Trek 2000 road bike
    - Two awesome and worn out Juliana saddles

 

 

Posting Permissions

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