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> We don't think an aluminium bike is better than a carbon fibre bike Depends on how you define better. Carbon bikes are prone to catastrophic failure, and if

by 323 4y ago

> We don't think an aluminium bike is better than a carbon fibre bike Depends on how you define better. Carbon bikes are prone to catastrophic failure, and if you fall often are a bad idea. Of course, you might just say "just don't fall".

TAKEMYMONEY 4y ago
Aluminum bikes are just as prone to failure, and in fact are less likely to be left in a repairable state after an accident. A dent or a crack in the frame ofter renders it useless. True of carbon as well, but they can be repaired in some cases; aluminum frames almost always need to be scrapped.
sudosysgen 4y ago
Yes, honestly, a good aluminium frame is preferable to carbon for 90% of people. The small tradeoff in weight and vibration/stiffness characteristics is really not worth the loss in structural integrity, money, and peace of mind.
- TAKEMYMONEY 4y ago
  Modern carbon frames are designed with structural integrity in mind, the frame-building process allows more fine-tuning than aluminum. Aluminum's best quality is it's value, you can wreck one and buy another and still have spent less than a low-grade CF frame.
  - sudosysgen 4y ago
    Not quite. Carbon fiber is a composite. Structural integrity is not one dimensional, and while carbon fiber frames are great in their intended loads, they are bad in puncture and abrasion, and that is inherent to carbon fiber. It is so much easier to wreck a carbon fiber frame than an alu frame. It just takes one pointy rock or one bad slide. Whereas an alu frame will only receive cosmetic damage
    - TAKEMYMONEY 4y ago
      That's a nuanced point to draw, thank you; most of my wrecks have been head-on, or from the side. I can patch my fiber frame though, it's getting harder to "total" them nowadays imo. I've tried!
      - sudosysgen 4y ago
        I see - I definitely haven't been keeping up that hard, so I may be surprised by recent improvements :)
  - deleted 4y ago
    [deleted]
z2h-a6n 4y ago
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?

by 323 4y ago

TAKEMYMONEY 4y ago

Aluminum bikes are just as prone to failure, and in fact are less likely to be left in a repairable state after an accident. A dent or a crack in the frame ofter renders it useless. True of carbon as well, but they can be repaired in some cases; aluminum frames almost always need to be scrapped.

sudosysgen 4y ago

Yes, honestly, a good aluminium frame is preferable to carbon for 90% of people. The small tradeoff in weight and vibration/stiffness characteristics is really not worth the loss in structural integrity, money, and peace of mind.

TAKEMYMONEY 4y ago
Modern carbon frames are designed with structural integrity in mind, the frame-building process allows more fine-tuning than aluminum. Aluminum's best quality is it's value, you can wreck one and buy another and still have spent less than a low-grade CF frame.
- sudosysgen 4y ago
  Not quite. Carbon fiber is a composite. Structural integrity is not one dimensional, and while carbon fiber frames are great in their intended loads, they are bad in puncture and abrasion, and that is inherent to carbon fiber. It is so much easier to wreck a carbon fiber frame than an alu frame. It just takes one pointy rock or one bad slide. Whereas an alu frame will only receive cosmetic damage
  - TAKEMYMONEY 4y ago
    That's a nuanced point to draw, thank you; most of my wrecks have been head-on, or from the side. I can patch my fiber frame though, it's getting harder to "total" them nowadays imo. I've tried!
    - sudosysgen 4y ago
      I see - I definitely haven't been keeping up that hard, so I may be surprised by recent improvements :)
- deleted 4y ago
  [deleted]

z2h-a6n 4y ago

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?