A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Are CF frames really safe?



 
 
Thread Tools Display Modes
  #1  
Old May 19th 17, 08:56 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 275
Default Are CF frames really safe?

With the price of a complete CF bicycle now approaching $1,000, one is tempted to buy one; however, I keep hearing stories about forks collapsing unexpectedly and without apparent reason.

Political commentator and devoted cyclist Victor Davis Hanson had such an accident some time back:

http://victorhanson.com/wordpress/th...giving-moment/

So I was wondering what you guys and gals think about this issue. Thanks for your opinions.
Ads
  #2  
Old May 19th 17, 09:08 PM posted to rec.bicycles.tech
Emanuel Berg[_2_]
external usenet poster
 
Posts: 1,035
Default Are CF frames really safe?

With the price of a complete CF bicycle now
approaching $1,000, one is tempted to buy
one; however, I keep hearing stories about
forks collapsing unexpectedly and without
apparent reason.


I've also heard these stories. When I was in
the shop the other day there was a discussion
about buying a frame from Asia and putting your
own sticker on it, so you had your own bicycle
brand (sort of). Some guy who did bikes from
the 80s said that's unsafe because they can
disintegrate, I actually think it was the fork
in this story as well. Some other guy said
"aren't the pro frames from Asia as well?" The
80s guy said, "yes, but they are tested in
Europe". No idea what is true in all of this.

--
underground experts united
http://user.it.uu.se/~embe8573
  #4  
Old May 19th 17, 10:35 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 3,345
Default Are CF frames really safe?

On Friday, May 19, 2017 at 12:56:36 PM UTC-7, wrote:
With the price of a complete CF bicycle now approaching $1,000, one is tempted to buy one; however, I keep hearing stories about forks collapsing unexpectedly and without apparent reason.

Political commentator and devoted cyclist Victor Davis Hanson had such an accident some time back:

http://victorhanson.com/wordpress/th...giving-moment/

So I was wondering what you guys and gals think about this issue. Thanks for your opinions.


I've had three carbon fiber forks break on me. One I don't remember about but apparently my group tell me it was a relatively harmless fall.

The second was a fork from IRS built in Italy. It literally exploded while I was leaning over to fix a clicking speedo pickup - no doubt a sign that it was going. I remember just bending over and then waking up 2 1/2 years later.

This one changed my entire life. I fell face first on the asphalt at about 5 mph and from only 18 to 24 inches up. I was knocked out for over 5 minutes. After they released me from the ER I was having seizures often enough that I had no short term memory. No short term memory = nothing to put into long term. I got into four car wrecks that totaled the vehicles. Between that and my condition being such that any charity could talk me into anything, my bank account went from $88,000 to $10,000.

Finally since none of the local neurologists had the slightest clue what was happening my best friend - a retired NCIS agent - took me over to the Stanford Cancer Center - I had lost 42% of my body weight - probably from forgetting to eat. All the doctors on my side of the bay assumed I had some sort of invisible cancer. I checked out clean and they recommended a Professor of Neurology that agreed to take me on as a patient after he gave some calls to the neurologists I was going to. My friend said he came back from the phone calls shaking his head.

It turns out that I had enough damage that I have several different types of seizures. The most common one's I have leave me with no memory of them occurring. A three months supply of medications cost me $200 and I'm on social security. I suppose I could get them mostly for free since I'm VFW but have never discovered the secret passwords. I'm still having some occasional seizures of an odd type that is somewhat self controllable. It's like having a nightmare with your eyes open and like a nightmare they don't make any sense after they happen.

Then late last year I was descending a fairly steep hill on my Colnago C40 and the fork failed just enough that I couldn't control the bike around a turn and not only traveled into the dirt ditch but the ditch ended in a rock culvert. As luck would have it I have bones almost like iron. I can't swim well because of that. (But you never want me to punch you.) That abrupt slamming into a rock wall at 25 mph would probably kill most people but I only felt like I had been killed. VERY sore muscles and abrasions. Something I would recommend you avoid.

There are CF bikes falling apart all over youTube. And the other day a man sent me a youTube reference after I said that aluminum bikes don't fail. He said that it was an aluminum MTB failing.

Well it wasn't - it was a supermarket steel MTB failing with the entire fork tube separating from the top and down tubes. This could not happen to a high quality steel bike and I've never heard of a high quality aluminum bike failing as we have several people in our group with aluminum bikes over 20 years old without a problem.

My recommendations is a medium high quality aluminum MTB with suspension or a high quality steel road bike. The exact tubing of the steel bikes isn't very important as long as it comes from a competent manufacturer. The Japanese make some very good bikes and their quality is equal to the Italians.

DO NOT believe anything you hear about carbon fiber. It they are "overbuilt" I'm sure they would be OK but the entire reason for CF is light weight and so they are all under-built. Colnago doesn't guarantee their bikes in Europe apparently and only allows a two year warranty for original owners.

Two days after my C40 accident my NCIS partner had the steering tube fall off of his C40 too. His small finger is now frozen half extended. He had a custom steel bike made for himself and his wife. The complete custom steel bike cost him less than half of an over-the-counter top end CF bike.

Around here CF bikes are not selling well anymore.
  #5  
Old May 19th 17, 10:57 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 275
Default Are CF frames really safe?

I tend to agree with you.

It really makes me wonder how the CF bike manufacturers handle their product liability claims. Do they actually buy insurance, or are they self-insured and simply fold the business if there are too many claims?

Ping Jay Beattie!
  #6  
Old May 20th 17, 12:51 AM posted to rec.bicycles.tech
JBeattie
external usenet poster
 
Posts: 5,870
Default Are CF frames really safe?

On Friday, May 19, 2017 at 2:57:24 PM UTC-7, wrote:
I tend to agree with you.

It really makes me wonder how the CF bike manufacturers handle their product liability claims. Do they actually buy insurance, or are they self-insured and simply fold the business if there are too many claims?

Ping Jay Beattie!


I haven't defended a carbon fork claim in many years. I've had exactly one case where there was a real screw-up -- a construction error (fork blade wasn't bonded, which is the CF equivalent of tack-brazing and failing to fully braze a steel fork). The problem with hand-made forks is that they're made by hand -- hands sometimes attached to absent minded people.

There are hundreds of thousands of CF forks in the market (maybe millions). There is no epidemic of failure. I've been riding on CF forks since 1990, and unlike TK, I haven't broken any. YMMV. I am not as confident of CF steerers, but so far, my forks with CF steerers have not failed.

Most large manufacturers are insured under policies with self-insured retentions of varying sizes, some large. Really large manufacturers may have "fronting" policies (really a form of self-insurance) or an off-shore insurance program where they are the insurance company. "Really large" means companies like Ford.

If you buy from a bike shop, then the shop's policy will respond as well since the shop is the ultimate seller, unless the state has some peculiar tort system that protects the ultimate seller. That's not the way it is on the West Coast. Shops always get sued, too.

Manufacturers like Trek and Specialized do rigorous QC. If in doubt, buy from a reputable company with a lifetime warranty and a US presence. I would steer clear of Colnago in light of TK's experience. Buy from a shop and not online.

-- Jay Beattie.











  #7  
Old May 20th 17, 03:04 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 5,697
Default Are CF frames really safe?

On Fri, 19 May 2017 12:56:32 -0700 (PDT),
wrote:

With the price of a complete CF bicycle now approaching $1,000, one is tempted to buy one; however, I keep hearing stories about forks collapsing unexpectedly and without apparent reason.

Political commentator and devoted cyclist Victor Davis Hanson had such an accident some time back:

http://victorhanson.com/wordpress/th...giving-moment/

So I was wondering what you guys and gals think about this issue. Thanks for your opinions.


A coupe of years ago I was talking to a chap I know in Singapore who
specializes in taking your old beat up bike and turning it into what
appears to be a brand new unridden bicycle. In the conversation he
mentioned that he also repairs CF bikes and we got into a conversation
about that. I asked him what make of CF bike commonly broke and he
said, "the cheap Chinese ones". At the time of the conversation he
stated that he averaged about one CF bike repair a week.
The population of Singapore was about 4.5 million at the time.

Having said that I rode a Giant OCR2 with a C.F. fork for two years
with no problems at all.
--
Cheers,

John B.

  #8  
Old May 20th 17, 03:11 AM posted to rec.bicycles.tech
Sir Ridesalot
external usenet poster
 
Posts: 5,270
Default Are CF frames really safe?

On Friday, May 19, 2017 at 10:05:17 PM UTC-4, John B. wrote:
On Fri, 19 May 2017 12:56:32 -0700 (PDT),
wrote:

With the price of a complete CF bicycle now approaching $1,000, one is tempted to buy one; however, I keep hearing stories about forks collapsing unexpectedly and without apparent reason.

Political commentator and devoted cyclist Victor Davis Hanson had such an accident some time back:

http://victorhanson.com/wordpress/th...giving-moment/

So I was wondering what you guys and gals think about this issue. Thanks for your opinions.


A coupe of years ago I was talking to a chap I know in Singapore who
specializes in taking your old beat up bike and turning it into what
appears to be a brand new unridden bicycle. In the conversation he
mentioned that he also repairs CF bikes and we got into a conversation
about that. I asked him what make of CF bike commonly broke and he
said, "the cheap Chinese ones". At the time of the conversation he
stated that he averaged about one CF bike repair a week.
The population of Singapore was about 4.5 million at the time.

Having said that I rode a Giant OCR2 with a C.F. fork for two years
with no problems at all.
--
Cheers,

John B.


My understanding of carbon fibre bicycles is that on the better quality ones the cloth is laid out in such a way as to give maxinum strength to the frame. Also, the resin used is confirmed to completely impregnate the carbon fiber cloth. On cheap carbon fiber bicycles the cloth is NOT laid out in the most optinum way to ensure that the frame is as strong as possible. Also, one the cheaper carbon fiber bicycles the cloth and/or the resin used may not be as good nor as carefully mixed and applied as it is on a better quality carbon fiber bicycle.

Cheers
  #9  
Old May 20th 17, 03:26 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 5,697
Default Are CF frames really safe?

On Fri, 19 May 2017 22:08:17 +0200, Emanuel Berg
wrote:

With the price of a complete CF bicycle now
approaching $1,000, one is tempted to buy
one; however, I keep hearing stories about
forks collapsing unexpectedly and without
apparent reason.


I've also heard these stories. When I was in
the shop the other day there was a discussion
about buying a frame from Asia and putting your
own sticker on it, so you had your own bicycle
brand (sort of). Some guy who did bikes from
the 80s said that's unsafe because they can
disintegrate, I actually think it was the fork
in this story as well. Some other guy said
"aren't the pro frames from Asia as well?" The
80s guy said, "yes, but they are tested in
Europe". No idea what is true in all of this.


Probably most bike frames come from Asia these days, but likely the
big names do ensure that the bikes are made to a standard. For
example, while I have no idea where Columbus C.F. frames and forks are
actually made, their catalog contains a statement, "All of the
products of Columbus Carbon Lab. are tested to, and exceed, the
requirements of European Standard CEN14781", and I would assume that
all European bike sellers adhere to similar standards.
--
Cheers,

John B.

  #10  
Old May 20th 17, 04:45 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 5,697
Default Are CF frames really safe?

On Fri, 19 May 2017 19:11:00 -0700 (PDT), Sir Ridesalot
wrote:

On Friday, May 19, 2017 at 10:05:17 PM UTC-4, John B. wrote:
On Fri, 19 May 2017 12:56:32 -0700 (PDT),
wrote:

With the price of a complete CF bicycle now approaching $1,000, one is tempted to buy one; however, I keep hearing stories about forks collapsing unexpectedly and without apparent reason.

Political commentator and devoted cyclist Victor Davis Hanson had such an accident some time back:

http://victorhanson.com/wordpress/th...giving-moment/

So I was wondering what you guys and gals think about this issue. Thanks for your opinions.


A coupe of years ago I was talking to a chap I know in Singapore who
specializes in taking your old beat up bike and turning it into what
appears to be a brand new unridden bicycle. In the conversation he
mentioned that he also repairs CF bikes and we got into a conversation
about that. I asked him what make of CF bike commonly broke and he
said, "the cheap Chinese ones". At the time of the conversation he
stated that he averaged about one CF bike repair a week.
The population of Singapore was about 4.5 million at the time.

Having said that I rode a Giant OCR2 with a C.F. fork for two years
with no problems at all.
--
Cheers,

John B.


My understanding of carbon fibre bicycles is that on the better quality ones the cloth is laid out in such a way as to give maximum strength to the frame. Also, the resin used is confirmed to completely impregnate the carbon fiber cloth. On cheap carbon fiber bicycles the cloth is NOT laid out in the most optinum way to ensure that the frame is as strong as possible. Also, one the cheaper carbon fiber bicycles the cloth and/or the resin used may not be as good nor as carefully mixed and applied as it is on a better quality carbon fiber bicycle.

Cheers


I don't know, but I do have a good friend in the
"fiberglass business" who uses C.F. from time to time and I've used it
once or twice.

My guess is that it isn't just the way that the cloth is laid that
differs but also the type of cloth used. Any of the fabrics used in
composites comes in a multitude of different weaves and thickness
which vary in cost. One of the smaller distributors lists 16 varieties
of C.F. cloth. But certainly some of the weaves are directional so
both the sequence and possibly the direction of the lay-up is
important.

To built a frame or fork three or four, or maybe more, different
weaves might be used to obtain optimum strength and they would be
required to be laid in a certain sequence. It would probably be much
cheaper to use only a single weave.

As for resin, again I'm not sure but anyone who is in the business
will want a resin that hardens consistently, but even a quick look at
epoxy sales houses revels a multitude of blends. As for the actual
mixing that probably isn't a major problem as mixing does effect the
hardening time and that is what would be of the most interest.
--
Cheers,

John B.

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
How safe is safe on your bicycle: what sort of differential is worthtalking about? Double? A magnitude? Andre Jute[_2_] Techniques 3 December 31st 13 12:21 AM
Since you can't be too safe... Frank Krygowski[_2_] Techniques 1 April 2nd 13 12:33 AM
Nobody is safe Mr Pounder UK 5 February 13th 13 01:09 PM
Think! Is your car safe? Doug[_3_] UK 276 March 15th 10 12:53 PM


All times are GMT +1. The time now is 02:25 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 CycleBanter.com.
The comments are property of their posters.