Catastrophic Failures of Carbon Bikes
#101
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I remember reading that the reason for the tire failures was dealership sales people deflating the tires on early Fjord Xplorers as they rode somewhat harshly (normal for a truck) so that the ride would seem smoother to prospective buyers. When those buyers drove those same vehicles, eventually the underinflated tires would fail and the trucks would go over sideways.
#104
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There's no way to make it a perfect test -- you can't test for every possible contingency. But as long as it the same for each material, it a fair test.
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Like what? All materials have their individual weaknesses, and the potential to fail. CF is no different.We don't know, CF bikes haven't been around that long but there are other CF items that have been around for a long time. Still, we could probably say the same thing about aluminum. Do you feel the same way about that material's longevity?
Bikes I like I tend to ride a long time, sometimes until they fail. I try to stay away from bikes with failure modes that are likely to cause me serious injury, especially bikes where minor damage that can lead up to such failures is likely to be hidden.
Ben
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Yes, Aluminum fails sooner or later. I have broken completely - a fork, hub flanges and seatposts, handlebars, bike racks (many), cranks ... I have seen cracks in rims, derailleur bodies, handlebars ... I make it a point of replacing stems and handlebars before they get too old. I don't have a set rule; I pick up a lot of those used but I rely on my gut feelings as to whether to continue riding older parts. Hubs and seatposts I don't sweat to much. They can be ride enders but have never cost me a crash. The fork cost me so much that I have zero interest in riding another material that could fail in similar manner.
Bikes I like I tend to ride a long time, sometimes until they fail. I try to stay away from bikes with failure modes that are likely to cause me serious injury, especially bikes where minor damage that can lead up to such failures is likely to be hidden.
Ben
Bikes I like I tend to ride a long time, sometimes until they fail. I try to stay away from bikes with failure modes that are likely to cause me serious injury, especially bikes where minor damage that can lead up to such failures is likely to be hidden.
Ben
Which is why these threads keep going in circles.
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My next most "experienced" bike saw two very hard crashes; new fork both times and finally was put to rest at mile 27,000 after being ridden into a fence and its wheelbase shortened most of a foot. (Fork, TT & DT.) I walked away unharmed. (I believe earlier in this thread I talked about steel bending and absorbing energy.) Stuff happens. I want bikes I am not afraid to ride after it does.
As I mentioned in a post above, I have had the catastrophic bike failure and paid the price. If it were to happen again, I do not want to live through it. Once is enough.
Ben
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"if cared for and properly maintained" and never crashed, knocked over, hit by tools that slipped or otherwise experienced real life stuff that happens. That doesn't describe my bikes. My Peter Money has been part of my life for (next year) 40 years. In that time, I have dropped the front wheel into a crack, had the front wheel come off (I still do not know why) andlaid it down on gravel to avoid riding into the side of a car driven by a young dad with a full car, late for church. Last summer I rode it down very steep gravel with deep potholes. It has also been in a moving van and crossed the country in a VW bus with everything I owned.
My next most "experienced" bike saw two very hard crashes; new fork both times and finally was put to rest at mile 27,000 after being ridden into a fence and its wheelbase shortened most of a foot. (Fork, TT & DT.) I walked away unharmed. (I believe earlier in this thread I talked about steel bending and absorbing energy.) Stuff happens. I want bikes I am not afraid to ride after it does.
As I mentioned in a post above, I have had the catastrophic bike failure and paid the price. If it were to happen again, I do not want to live through it. Once is enough.
Ben
My next most "experienced" bike saw two very hard crashes; new fork both times and finally was put to rest at mile 27,000 after being ridden into a fence and its wheelbase shortened most of a foot. (Fork, TT & DT.) I walked away unharmed. (I believe earlier in this thread I talked about steel bending and absorbing energy.) Stuff happens. I want bikes I am not afraid to ride after it does.
As I mentioned in a post above, I have had the catastrophic bike failure and paid the price. If it were to happen again, I do not want to live through it. Once is enough.
Ben
#109
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I've seen CF handlebar and CF seat post fail and snap, both of these failures happened to mountain bikers while they were riding on the trail. The funny thing is that it failed while they were riding on the smooth easy part of the trail and not while going through rock gardens...I suspect that there are a lot of CF frames and forks failures out there which people don't report and never go public with it.
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In museums there are steel bikes that are approx 120 years old. Put some new tires on them, and there would be no worry of riding them. That begs the question if you would want to ride a CF bike that is 120 years old? Because the way plastic ages, I bet if you would even just tapped a a CF frame that old it would shatter.
#111
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In museums there are steel bikes that are approx 120 years old. Put some new tires on them, and there would be no worry of riding them. That begs the question if you would want to ride a CF bike that is 120 years old? Because the way plastic ages, I bet if you would even just tapped a a CF frame that old it would shatter.
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In museums there are steel bikes that are approx 120 years old. Put some new tires on them, and there would be no worry of riding them. That begs the question if you would want to ride a CF bike that is 120 years old? Because the way plastic ages, I bet if you would even just tapped a a CF frame that old it would shatter.
I find it funny that you always hear people complaiin about how plastic doesn't break down in landfills or in the ocean, but if you make a bike frame out of it, suddenly it's useful life drops to months.
There are valid reasons ppl may not want a composite frame, that is fine. I would never tell ppl what to buy. Just don't spread ignorance and myths.
#113
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You are wrong. I don't know where you get your info but it is not true. In 120 years, a well made composite bike will look and and perform just as well as the day it was made.
I find it funny that you always hear people complaiin about how plastic doesn't break down in landfills or in the ocean, but if you make a bike frame out of it, suddenly it's useful life drops to months.
There are valid reasons ppl may not want a composite frame, that is fine. I would never tell ppl what to buy. Just don't spread ignorance and myths.
I find it funny that you always hear people complaiin about how plastic doesn't break down in landfills or in the ocean, but if you make a bike frame out of it, suddenly it's useful life drops to months.
There are valid reasons ppl may not want a composite frame, that is fine. I would never tell ppl what to buy. Just don't spread ignorance and myths.
I'd be more concerned with a CF fork, handlebars, stem, crank or seat post failing and seriously injuring me than a frame.
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Agreed, but sometimes you just have to have fun in a thread like this, and I have to admit I found this funny:
To those who posted ****, ha ha. No one has broken the forum rules and the thread rolls on!
I'd be more concerned with a CF fork, handlebars, stem, crank or seat post failing and seriously injuring me than a frame.
To those who posted ****, ha ha. No one has broken the forum rules and the thread rolls on!
I'd be more concerned with a CF fork, handlebars, stem, crank or seat post failing and seriously injuring me than a frame.
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I'm taking a Boeing 787 to Asia next year. I'll ask to inspect the plane before take-off.
What sort of defects should I be looking for?
What sort of defects should I be looking for?
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When I was looking to purchase my first road bike I narrowed my must-have features to:
Shimano 105 gear set
Full carbon fiber fork
Weigh less than 20 lbs.
I found those things in a Fuji Roubaix 1.3…
I must admit from the perspective of a new road bike rider who assumed a full fiber carbon fork was a step-up, reading all of this conflict about CF is a bit disconcerting.
Shimano 105 gear set
Full carbon fiber fork
Weigh less than 20 lbs.
I found those things in a Fuji Roubaix 1.3…
I must admit from the perspective of a new road bike rider who assumed a full fiber carbon fork was a step-up, reading all of this conflict about CF is a bit disconcerting.
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When I was looking to purchase my first road bike I narrowed my must-have features to:
Shimano 105 gear set
Full carbon fiber fork
Weigh less than 20 lbs.
I found those things in a Fuji Roubaix 1.3…
I must admit from the perspective of a new road bike rider who assumed a full fiber carbon fork was a step-up, reading all of this conflict about CF is a bit disconcerting.
Shimano 105 gear set
Full carbon fiber fork
Weigh less than 20 lbs.
I found those things in a Fuji Roubaix 1.3…
I must admit from the perspective of a new road bike rider who assumed a full fiber carbon fork was a step-up, reading all of this conflict about CF is a bit disconcerting.
Going from that to a full carbon frame was kind of a letdown because there was no ahhh moment. It's a bike frame, it does its job.
Don't worry about all of the hand wringing about composite failing. Most of it comes from people who really don't understand the technology and unless your going to push your bike to its design limits you will never have an issue.
#119
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"I'd be more concerned with a CF fork, handlebars, stem, crank or seat post failing and seriously injuring me than a frame. "
A friend of mine had Easton carbon bars that snapped on him right at the brake lever clamp. A customer had the down tube split wide open on the bottom while riding. Another friend lost a 6 inch section of seat stay on his carbon frame when his buddy kicked it. A fella at a mountain bike race dropped his bike against a water pipe and the tube splintered. I had a carbon seat post fail on my road bike.
The Easton bars may have failed due to over torque of the brake lever clamp. The down tube split due to hitting a car 6 months prior to the catastrophic event. The seat stay failure is obvious, however it would not have failed if it were metal. The mountain bike failure was very thin walled and cold air temp. The seat post failed where the head is bonded to the tube. The bond was fine, but the tube was not. Only about 4 inches of tube sticks out of the frame so I know it was not over extended.
I put the carbon fork from my ti bike in the trash earlier this year and put a nice steel fork on it. Rides much better and after 5 years with the carbon fork I was not going to see if the 5 year warranty was any good. Will never put carbon on anything again.
A friend of mine had Easton carbon bars that snapped on him right at the brake lever clamp. A customer had the down tube split wide open on the bottom while riding. Another friend lost a 6 inch section of seat stay on his carbon frame when his buddy kicked it. A fella at a mountain bike race dropped his bike against a water pipe and the tube splintered. I had a carbon seat post fail on my road bike.
The Easton bars may have failed due to over torque of the brake lever clamp. The down tube split due to hitting a car 6 months prior to the catastrophic event. The seat stay failure is obvious, however it would not have failed if it were metal. The mountain bike failure was very thin walled and cold air temp. The seat post failed where the head is bonded to the tube. The bond was fine, but the tube was not. Only about 4 inches of tube sticks out of the frame so I know it was not over extended.
I put the carbon fork from my ti bike in the trash earlier this year and put a nice steel fork on it. Rides much better and after 5 years with the carbon fork I was not going to see if the 5 year warranty was any good. Will never put carbon on anything again.
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Then you are being remarkably short sighted. Give up travel altogether is my advice, carbon fibre has infested every form of transport !
#121
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A friend of mine had Easton carbon bars that snapped on him right at the brake lever clamp. A customer had the down tube split wide open on the bottom while riding. Another friend lost a 6 inch section of seat stay on his carbon frame when his buddy kicked it. A fella at a mountain bike race dropped his bike against a water pipe and the tube splintered. I had a carbon seat post fail on my road bike.
The Easton bars may have failed due to over torque of the brake lever clamp. The down tube split due to hitting a car 6 months prior to the catastrophic event. The seat stay failure is obvious, however it would not have failed if it were metal. The mountain bike failure was very thin walled and cold air temp. The seat post failed where the head is bonded to the tube. The bond was fine, but the tube was not. Only about 4 inches of tube sticks out of the frame so I know it was not over extended.
The Easton bars may have failed due to over torque of the brake lever clamp. The down tube split due to hitting a car 6 months prior to the catastrophic event. The seat stay failure is obvious, however it would not have failed if it were metal. The mountain bike failure was very thin walled and cold air temp. The seat post failed where the head is bonded to the tube. The bond was fine, but the tube was not. Only about 4 inches of tube sticks out of the frame so I know it was not over extended.
I put the carbon fork from my ti bike in the trash earlier this year and put a nice steel fork on it. Rides much better and after 5 years with the carbon fork I was not going to see if the 5 year warranty was any good. Will never put carbon on anything again.
#122
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"Some carbon fiber parts or tubing (frame or fork) are constructed with very thin walls, so thin that you may be able to flex the walls with your fingers. During an inspection, you may need to use this technique. However, it is not good for the carbon fiber and adds stress to the structure. Such stress accumulates over time, so avoid unnecessary flexing of the carbon fiber when possible."
So you may need to "flex the walls" during inspection, but avoid doing so unnecessarily!
"An overloaded carbon fiber part will not bend or deform, so a damaged carbon part (with reduced strength due to the damage) may look normal—even after the same load that bent the metal part. But when the sum of the forces finally exceeds the strength limit of the carbon fiber, the carbon fiber part breaks, it does not bend"
"In an accident or impact that does not visibly break the carbon fiber part, the carbon fiber could still have internal or hidden damage."
"Carbon fiber parts with damage can break suddenly, causing serious injury or death. Carbon fiber can conceal damage from an impact or crash."
"Carefully inspect your frame and components for signs of fatigue before and after each ride.
Unlike metal parts, carbon composite parts that have been damaged may not bend, bulge, or deform; a damaged part may appear to be normal to a cursory glance. After any high force load, like a crash or other impact to your bicycle, thoroughly inspect all the parts of your bicycle, and use the following procedures to inspect carbon composite parts:
• Check for scratches, gouges, or other surface problems.
• Check the part for loss of rigidity.
• Check the part for delamination.
• Listen for unusual noises.
These tests may not be conclusive. The tests are difficult to describe, so as an aid to describing the tests we provide a movie of a composite part inspection. If you have any doubts about the integrity of a part, do not ride the bicycle."
So check for all these things "before and after each ride", but there still may be hidden damage. This is not someone (me) spreading ignorance and myths, it's all from a Gary Fisher bicycle manual.
Carbon fiber composite inspection procedures
#123
Senior Member
Almostrick, that is exactly why there are no longer any carbon bits on any of my bikes. Worry free living beats the heck out of the other option.
BTW, anyone who states to have used "carbon frame" or "carbon parts" inspected by an expert before purchasing is out of touch with reality. The shop I work in will not inspect frames for defects. Way too much liability! The only way to thoroughly inspect carbon is via xray examination as it will reveal cracks that cannot be detected by the human eye. I never saw the crack in the seat post until it failed. On my son's aluminum frame a crack in the seat stay creaked for a long time and then opened up which was easily seen in a visual inspection. It never broke off. Carbon is rarely that forgiving.
Yep, wings on newer airplanes are carbon. I bet they have a much shorter service life than the aluminum wings of previous generations. Carbon is everywhere, but it doesn't mean it is always a good idea.
BTW, anyone who states to have used "carbon frame" or "carbon parts" inspected by an expert before purchasing is out of touch with reality. The shop I work in will not inspect frames for defects. Way too much liability! The only way to thoroughly inspect carbon is via xray examination as it will reveal cracks that cannot be detected by the human eye. I never saw the crack in the seat post until it failed. On my son's aluminum frame a crack in the seat stay creaked for a long time and then opened up which was easily seen in a visual inspection. It never broke off. Carbon is rarely that forgiving.
Yep, wings on newer airplanes are carbon. I bet they have a much shorter service life than the aluminum wings of previous generations. Carbon is everywhere, but it doesn't mean it is always a good idea.
#124
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Actually, Ford had a lower pressure for the purpose of meeting bumper height regulations. The pressure was adequate for the vehicle, and would not lead to failure, but people are horrible at maintaining proper tire pressure. The recommended pressure was such that if it wasn't maintained, tire damage could occur, and did. Firestone took the blame the first time, despite it not really being their fault. The tires were not defective. The second time around they did not take the blame. Ford recalled the Explorers and lowered them. My wife had one, and had the recall done.
https://www.nytimes.com/1978/08/06/a...s-against.html
#125
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I'm not sure where you are getting this info or if you are making it up but much of this is nonsense.
The following is for bikes, but should be of some help:
"Some carbon fiber parts or tubing (frame or fork) are constructed with very thin walls, so thin that you may be able to flex the walls with your fingers. During an inspection, you may need to use this technique. However, it is not good for the carbon fiber and adds stress to the structure. Such stress accumulates over time, so avoid unnecessary flexing of the carbon fiber when possible."
So you may need to "flex the walls" during inspection, but avoid doing so unnecessarily!
"An overloaded carbon fiber part will not bend or deform, so a damaged carbon part (with reduced strength due to the damage) may look normal—even after the same load that bent the metal part. But when the sum of the forces finally exceeds the strength limit of the carbon fiber, the carbon fiber part breaks, it does not bend"
"In an accident or impact that does not visibly break the carbon fiber part, the carbon fiber could still have internal or hidden damage."
"Carbon fiber parts with damage can break suddenly, causing serious injury or death. Carbon fiber can conceal damage from an impact or crash."
"Carefully inspect your frame and components for signs of fatigue before and after each ride.
Unlike metal parts, carbon composite parts that have been damaged may not bend, bulge, or deform; a damaged part may appear to be normal to a cursory glance. After any high force load, like a crash or other impact to your bicycle, thoroughly inspect all the parts of your bicycle, and use the following procedures to inspect carbon composite parts:
• Check for scratches, gouges, or other surface problems.
• Check the part for loss of rigidity.
• Check the part for delamination.
• Listen for unusual noises.
These tests may not be conclusive. The tests are difficult to describe, so as an aid to describing the tests we provide a movie of a composite part inspection. If you have any doubts about the integrity of a part, do not ride the bicycle."
So check for all these things "before and after each ride", but there still may be hidden damage. This is not someone (me) spreading ignorance and myths, it's all from a Gary Fisher bicycle manual.
Carbon fiber composite inspection procedures
"Some carbon fiber parts or tubing (frame or fork) are constructed with very thin walls, so thin that you may be able to flex the walls with your fingers. During an inspection, you may need to use this technique. However, it is not good for the carbon fiber and adds stress to the structure. Such stress accumulates over time, so avoid unnecessary flexing of the carbon fiber when possible."
So you may need to "flex the walls" during inspection, but avoid doing so unnecessarily!
"An overloaded carbon fiber part will not bend or deform, so a damaged carbon part (with reduced strength due to the damage) may look normal—even after the same load that bent the metal part. But when the sum of the forces finally exceeds the strength limit of the carbon fiber, the carbon fiber part breaks, it does not bend"
"In an accident or impact that does not visibly break the carbon fiber part, the carbon fiber could still have internal or hidden damage."
"Carbon fiber parts with damage can break suddenly, causing serious injury or death. Carbon fiber can conceal damage from an impact or crash."
"Carefully inspect your frame and components for signs of fatigue before and after each ride.
Unlike metal parts, carbon composite parts that have been damaged may not bend, bulge, or deform; a damaged part may appear to be normal to a cursory glance. After any high force load, like a crash or other impact to your bicycle, thoroughly inspect all the parts of your bicycle, and use the following procedures to inspect carbon composite parts:
• Check for scratches, gouges, or other surface problems.
• Check the part for loss of rigidity.
• Check the part for delamination.
• Listen for unusual noises.
These tests may not be conclusive. The tests are difficult to describe, so as an aid to describing the tests we provide a movie of a composite part inspection. If you have any doubts about the integrity of a part, do not ride the bicycle."
So check for all these things "before and after each ride", but there still may be hidden damage. This is not someone (me) spreading ignorance and myths, it's all from a Gary Fisher bicycle manual.
Carbon fiber composite inspection procedures