oddjob2

NY TIMES article here.

https://www.nytimes.com/2014/07/27/sp...temail0=y&_r=0

iab

Rerun - https://www.bikeforums.net/classic-vi...-ny-times.html

But what I find interesting is that the NY Times finds itself fit to get into the pissing contest with at best hersey anecdotal evidence. Quite sad for a distinguished publication.

gomango 

Agreed.

Flimsy journalism at best. I am used to better from them.

RobbieTunes

The entire article is just conversation, with a little bit of background. I saw no factual value in it. I guess the 787's wings will fall off. One wonders if it's driven by the tons of words and speculation generated when Contador's bike, while mounted on a car, hit another bike that was mounted on a car, and broke. All that proves is that the mounting points on the car were stronger than the bike's frame, given the forces that acted upon it.

This is the thrust of NYT priorities, when the bailed-out GM is having to recall millions of vehicles, many sold at "average" 10-15% price increases that helped GM make $4B last quarter. They'd rather rag on Walmart.

Still, and I stereotype here, the typical NYT reader will take it as gospel and spread it. Having been to a couple of cocktail parties inside the beltway, I guarantee that article was paraphrased whenever a cyclist or triathlete paused long enough between free wine and crackers to join a conversation.

mrmw

Walmart is the carbon bike frame of retailers. :-)

John E

It all depends on your application and your maintenance practices. For John Q. Public, bicycle weight reduction probably has been overdone -- I, for one, gladly take a weight penalty in the interest of greater longevity and reliability. If you do have carbon rims and/or forks, it certainly does pay to inspect them frequently.

iab

Why is that?

I can categorically state that the rims on top, laced 18/24 radial and 2x, and 1100 grams are stronger and more durable than the rims below 36/36 3x and around 1900 grams. You literally can put your entire weight on an unlaced version of the upper rims where the unlaced version of the lower rims will taco just leaning on them. The uppers will also take much more spoke tension than the lowers without any worry.

Cinelli XCR with Super Record 001 by iabisdb, on Flickr

Cinelli_Model_B 004 by iabisdb, on Flickr

Sir_Name 

Oh yes. Strength comes from the combination of geometry and materials (fatigue aside within certain considerations); weight hangs in balance between the three. Someone(s) performed a delicate balancing act in the top image and the results are beautiful (to me at least).

Very nice.
Gorgeous Cinellis.

kaliayev

Yep. If carbon is ready to fail there is little chance of discovering it until it does.

iab

Why is that? Can you tell when an aluminum wheel will taco?

kaliayev

Why is that? Can you tell when carbon components will fail?

Sir_Name 

I think that's the point.

iab

Correct.

I have no problem if someone makes a claim about carbon, steel or aluminum. But without science to back the claim, it is all rubbish.

jeirvine 

Yeah that article was thin, and missed a good opportunity to actually do some research and get beyond hearsay. I'll wait for the well researched New Yorker long form version. But my completely uninformed opinion is that I will not buy a used carbon frame, and have had no qualms about buying 40-50 year old steel bikes and riding them hard. I would not even know what to look for in a frequent carbon inspection. Is there such a thing as invisible damage that will fail unexpectedly? The NYT implies it, but doesn't back it up.

Sir_Name 

"Doug Perovic, a professor of materials science and engineering at the University of Toronto, said that carbon fiber was a bit like a diamond: strong while not being particularly tough."

"What results, Perovic said, is that when a bike is stressed beyond its limits, it “fractures into many pieces while metals bend, the energy absorption is the bending.” While steel and aluminum bikes generally telegraph an impending failure by displaying cracks, carbon fiber generally fails without warning."

"Greve and Perovic agreed that for consumers who are not constantly banging their bikes around on team vehicles"... [an interesting way to put it when considering current events] ..."and who are unlikely to be involved in crashes, the risks in buying a carbon bike made by a reputable company should be minimal. Greve said many riders had told him that the performance gains from superlight frames reached the point of diminishing returns long ago, and he questions the wisdom of consumers’ buying what are, in effect, very costly throwaway items if they crash."

Ductility versus brittleness. Use materials within their means and you're a-okay. Understand and choose wisely.

iab

There is no doubt that carbon fails in a different manner than steel or aluminum. But I won't ride a fork that is bent nor will I wide a fork that is cracked.

RobbieTunes

I do worry about my $92 FSA Plasma bars, direct from China.....but I probably shouldn't.

Meanwhile, my 1988 Miele steel bike sits, with 3x7 RSX STI, for $350, and novices are bringing me Kestrel Talon tri-bikes, in the box, they got somewhere for $1100 shipped. On a time basis, I'm much better off charging to assemble bikes than upgrading nice steel frames for that 1 in 100 rider who will want the Miele, but I'm good either way. They both roll.

iab

Cino Cinelli only produced steel stems bars until 1963 when he started aluminum production. He used an aluminum stem and bars (manubrio d'Ambrosio duralluminio) when he raced on Frejus.

Guerin_Campania3 by iabisdb, on Flickr

gomango 

New bars?

Ride them.

Old Easton cf bars that came on my Merckx? The ones with the hairline crack.

Off to the trash can pronto.

Michael Angelo 

Each and every time I go to the LBS, I see cracked carbon frames , broken cracked carbon forks, cracked broken Carbon rims, cracked broken carbon stems, handlebars and seat rails. I think I'll stay with metal.

crank_addict

rolleyes

Ridiculous analogy and drummed up drama. Folk's, its a 'racing bike'....purpose built. And, especially about a sport with high risk, crashes OFTEN happen.

What's the NYT point of the article? Hidden agenda? Perhaps some lawyer prep for a case and planning to use the NYT experts as a witness- LOL. Or are some Tarmac owners freaking they might have a major deprecating bike? Are pro racers really crying? The so called 'code of silence'.... spare me some more. If joe consumer wants to emulate a pro racer (and most don't have the budget of a factory team and can throw away $15k bikes), expect to toss it away after a crash.

Like an absurdly expensive F1 tub, its absolutely purpose built and has limited longevity - crashed or NOT. And like pro cycling, takes mega budget to support teams and win. Why in the world would anyone go with old technology? You don't see F1 chassis made of chromo...... jeez.


Sort of funny discussing all of this on a C&V forum but I guess we could save someone's butt warning of old racing bikes with rusty thin tubes. That said, far from being a racer I want a wicked built CF bike and FULLY understand the risk. The technology intrigues me and I appreciate all that's involved with making them.

A bit more: Twenty five years ago I had a full CF monocoque hard tail MTN bike (23 lbs. complete XT w/ Ti hardware, radial 1/2 on the rear and radial - radical built front wheels), rode it for some time with a rigid fork and later suspended fork. Designs and layups were obviously different but it took a few good slams and one very hard crash. Never had a frame issue. BTW: I also had one of the first full CF stem and bar on the same bike. I had complete confidence in all of it. Of course, should a hit resulted in chipped bars or whatever, (fortunately which never happened), common sense would have told me to replace it.

crank_addict

Good to keep your mind at ease and in you're opinion, seem very practical to have a steel bike. But just because of seeing cracked CF frames / related shouldn't assume its a horrible atrocity of bike manufacturing or the misleading of 'joe wanna be a bike racer'. All have a story you may not know about.

kunsunoke 

Nobody in their right mind would do those things - deliberately.

Carbon requires skill in fabrication and intensive quality assurance throughout the process. The fibers need to be oriented properly, and the resin free of voids and properly formulated. Get it right and you have a lightweight material that outperforms wonder-metals (titanium, scandium/Al alloy). Get it wrong it means you've built an expensive, aesthetically-attractive deathtrap for America's cycling dentists.

When frames were being made in the Americas by high-tech companies (Kestrel, Trek) they were over-built. Sometimes that resulted in a dead-feeling frame. The riders were kept from the slings and arrows of failures, however, because the pioneers of the technology had to ensure it held up in an overly-litigious society. And the builders had the good sense to keep the material protected from crush and impact damage by limiting what they used it for.

Older carbon mountain bikes (particularly those by Trek and Miyata) could be hammered on quite hard, without breakage. Greg Herbold was noted for his particular signature bike, which he rode with reckless abandon. Some of the early Alan carbon bikes are still around and still kicking.

Made properly, carbon was good stuff - which is why it's grown so spectacularly in use for bikes, golf club shafts, fishing poles and race car bodies. Unfortunately, some of the companies promoting carbon bikes decided to go whole-hog into parts that were better made from metals (such as handlebars, steering tubes, seat posts, rims and wheels).

And then they doubled-down by farming out production to the People's Republic of China.

Does anyone here seriously think that a Guangzhou-based factory manager really gives a flying **** about how his frames and parts are holding up in America? Cutting corners gets that guy paid better. And that manager is only held accountable if the inevitable part failures embarrass some party apparatchik in Beijing.

kunsunoke 

The New Yorker version will likely be similarly deficient, and also more pretentious (in addition to being more wretchedly-written). Truthfully, though, it's hard to popularize materials engineering for the masses.

Yes.

https://service.specialized.com/colla...tion-Guide.pdf

Sinyard's people came out with this service bulletin after several S-works road bikes had broken under riders.

Crush damage of a carbon steering tube is invisible, and hidden. The steering tubes would likely never have snapped had they been made from aluminum, titanium or chrome-molybdenum steel.

Moral -

1) Don't use carbon for crush sensitive areas on the bike.
2) See item 1) when garage mechanics are involved in the build process.