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Out of curiosity, do you have any sources with actual evidence that carbon fiber is prone to catastrophic failure in bike frames/components, particularly compar

Out of curiosity, do you have any sources with actual evidence that carbon fiber is prone to catastrophic failure in bike frames/components, particularly compared to aluminum? From my (rather limited) research, there seems to be plenty of speculation and anecdotes online about the fragility of CF, but not much actual evidence of rates of catastrophic failure. My impression (not based on expertise or much evidence) is that properly designed CF is much stronger for a given weight than most metals, but can fail at relatively low loads if stressed in a way it wasn't designed for. As it applies to biking, I guess this would tend to mean that CF bikes are more likely to be structurally damaged because of a crash/fall, but not necessarily more likely to fail and cause a crash/fall. This of course supports your point that CF is not a good choice for someone who falls often.

323 4y ago
> Now that use of the material, once reserved for high-end bikes, has become widespread in the bike industry, reports of accidents and mysterious failures are on the rise. > Reed and other experts in carbon fiber agree that any material can fail. Wrecks happen from faulty aluminum, steel, and even rock-hard titanium. The difference with carbon fiber is that it can be difficult to detect signs of damage that might signal imminent failure. Cracks and dents in other materials are typically easy to see, but fissures in carbon fiber often hide beneath the paint. What’s worse is that when carbon fiber fails, it fails spectacularly. While other materials might simply buckle or bend, carbon fiber can shatter into pieces, sending riders flying into the road or trail. And this kind of catastrophic destruction can happen to any part of a bike made with the material. > “It’s completely reasonable for someone who wants a lightweight bike to look at carbon fiber, but they need to understand the risks,” Elrath says. “Absolutely this is getting ignored.” https://www.outsideonline.com/outdoor-gear/bikes-and-biking/carbon-fiber-bike-accidents-lawsuits/ https://www.outsideonline.com/outdoor-gear/bikes-and-biking/... There are plenty of videos from competitions where the carbon suddenly fails. I've never seen that with aluminum bikes. Last three accidents from 4:15: https://www.youtube.com/watch?v=kpeTiF_Tm04 https://www.youtube.com/watch?v=kpeTiF_Tm04 But going back, if one is not racing, is it really worth the extra risk for minor performance improvements? Some say that after any serious fall/crash a carbon frame/component should be replaced because it's difficult to assess if it was damaged or not. How many can afford that?
- z2h-a6n 4y ago
  I was hoping for some actual data. As I mentioned there's plenty of anecdata online, but I don't know if anyone has really studied this. The article you linked to suggests that nobody has done a systematic study. As a counterpoint to the video you linked, I'm reminded of this video of Danny Macaskill having to work pretty hard to break a carbon rim: https://www.youtube.com/watch?v=VfjjiHGuHoc https://www.youtube.com/watch?v=VfjjiHGuHoc > ... if one is not racing, is it really worth the extra risk for minor performance improvements? It really depends on how much extra risk there is and how much the rider values the performance improvements. Without actual data about the (relative) risk of carbon fiber failure in bike components, we have to guess based on the information we have avaliable. Most of this seems to either be anecdotal, or coming from from interested parties, e.g. bike manufacturers, lawyers who make their living suing bike manufacturers, and journalists who are probably more interested in writing about something exciting happening than something exciting not happening. My impression is that the relative risk of of using carbon fiber in some (but perhaps not all) bike components is pretty small compared to the other risks involved in biking, and the performance improvements are big enough to be worth it for me, even though I don't race.

323 4y ago

> Now that use of the material, once reserved for high-end bikes, has become widespread in the bike industry, reports of accidents and mysterious failures are on the rise. > Reed and other experts in carbon fiber agree that any material can fail. Wrecks happen from faulty aluminum, steel, and even rock-hard titanium. The difference with carbon fiber is that it can be difficult to detect signs of damage that might signal imminent failure. Cracks and dents in other materials are typically easy to see, but fissures in carbon fiber often hide beneath the paint. What’s worse is that when carbon fiber fails, it fails spectacularly. While other materials might simply buckle or bend, carbon fiber can shatter into pieces, sending riders flying into the road or trail. And this kind of catastrophic destruction can happen to any part of a bike made with the material. > “It’s completely reasonable for someone who wants a lightweight bike to look at carbon fiber, but they need to understand the risks,” Elrath says. “Absolutely this is getting ignored.” https://www.outsideonline.com/outdoor-gear/bikes-and-biking/carbon-fiber-bike-accidents-lawsuits/ https://www.outsideonline.com/outdoor-gear/bikes-and-biking/... There are plenty of videos from competitions where the carbon suddenly fails. I've never seen that with aluminum bikes. Last three accidents from 4:15: https://www.youtube.com/watch?v=kpeTiF_Tm04 https://www.youtube.com/watch?v=kpeTiF_Tm04 But going back, if one is not racing, is it really worth the extra risk for minor performance improvements? Some say that after any serious fall/crash a carbon frame/component should be replaced because it's difficult to assess if it was damaged or not. How many can afford that?

z2h-a6n 4y ago
I was hoping for some actual data. As I mentioned there's plenty of anecdata online, but I don't know if anyone has really studied this. The article you linked to suggests that nobody has done a systematic study. As a counterpoint to the video you linked, I'm reminded of this video of Danny Macaskill having to work pretty hard to break a carbon rim: https://www.youtube.com/watch?v=VfjjiHGuHoc https://www.youtube.com/watch?v=VfjjiHGuHoc > ... if one is not racing, is it really worth the extra risk for minor performance improvements? It really depends on how much extra risk there is and how much the rider values the performance improvements. Without actual data about the (relative) risk of carbon fiber failure in bike components, we have to guess based on the information we have avaliable. Most of this seems to either be anecdotal, or coming from from interested parties, e.g. bike manufacturers, lawyers who make their living suing bike manufacturers, and journalists who are probably more interested in writing about something exciting happening than something exciting not happening. My impression is that the relative risk of of using carbon fiber in some (but perhaps not all) bike components is pretty small compared to the other risks involved in biking, and the performance improvements are big enough to be worth it for me, even though I don't race.