JENNIFER LUDDEN, HOST:
For people who like high-performance bicycles, carbon fiber is something of a wonder material. It's strong and lightweight. But it has a downside. Damage to bikes with carbon fiber frames or components can be hard to spot and potentially catastrophic. Reporter Jeff Tyler considers some of the risks.
JEFF TYLER, BYLINE: On a perfect sunny day in Santa Barbara four years ago, Cynthia Walker went on a bike ride with a friend. She was writing an 8-year-old bike made by TIME, a top-of-the-line French brand that retailed for $5,000.
CYNTHIA WALKER: We had just started our ride. And we're on a flat road. And the next thing I know, I was on the ground in a pool of blood. And I remember my friend saying he was picking up my teeth from the pavement.
TYLER: A small twig got caught in the spokes, and the bike frame shattered.
WALKER: It just imploded on me without any warning at all.
TYLER: Generally speaking, a twig is not enough to cause a carbon fiber frame to shatter. That is, unless there was prior damage to the bike. But Walker says there wasn't.
WALKER: I had just had it looked over by one of the best bike mechanics in town. He didn't notice anything unusual. And I'd taken really good care of the bike. I'd never crashed on it before.
TYLER: After the accident, she got the bike inspected at a lab.
WALKER: The results were that it was bad epoxy. That's what the expert said. It wasn't really made well.
TYLER: TIME did not respond to a request for comment. While these kinds of accidents are rare, they do happen. An online article from Outside magazine last month highlighted other examples of carbon bikes failing seemingly out of nowhere. Many in the industry dismiss such accidents, insisting that riders aren't taking responsibility for damaging their bikes. But some experts disagree.
LUKE ELRATH: In some cases, there is a legitimate design or manufacturing defect in the carbon fiber that leads to a failure of use under normal conditions.
TYLER: That's forensic investigator Luke Elrath with Robson Forensic. He's handled 12 cases involving carbon fiber bike defects in the last six years. Elrath says it can be hard for people to identify problems in carbon fiber bikes.
ELRATH: Carbon fiber is unique in that it can sometimes be very difficult to identify these cracks before they are able to propagate and fail catastrophically and often without warning.
TYLER: Nonetheless, Elrath does not recommend that consumers abandon carbon fiber bikes. He rides one himself. He says people just need to be aware that these bikes require extra maintenance and regular inspections. Read that owner's manual closely. Avoid overtightening carbon fiber components, like the seatpost. And if you crash your bike, or if you're shopping for a used bike, get it checked out by an expert.
(SOUNDBITE OF DOOR CLOSING)
TYLER: Someone like Hern Montenegro. In his cluttered workshop near downtown Los Angeles, he inspects carbon fiber bikes and does repairs, too. One test involves tapping the carbon fiber with a coin.
(SOUNDBITE OF COIN TAPPING)
HERN MONTENEGRO: That's solid.
(SOUNDBITE OF COIN TAPPING)
MONTENEGRO: When it's broken, it sounds a little flat.
(SOUNDBITE OF COIN TAPPING)
MONTENEGRO: That's cracked.
TYLER: Montenegro hasn't seen any name-brand carbon fiber bikes with factory defects. But he has seen a bunch of counterfeits - bikes that look like a $5,000 Pinarello that are really just cheap knockoffs. Multiple experts told me that counterfeit carbon fiber bikes pose a greater risk than factory defects from a reputable brand. And the big-name bicycle companies say their bikes have never been safer.
MARK SCHROEDER: We run critical parts of the products through X-ray to make sure that we find that there's no flaws in the products we're selling.
TYLER: That's Mark Schroeder, the director of engineering at Specialized Bicycles.
SCHROEDER: Carbon fiber products do not all come out of the same factory in China. The counterfeit websites and the low-cost carbon fiber makers on the Internet would like to tell you that, and they'd like you to believe that. But at Specialized, we have our own exclusive factories for carbon fiber, and I believe the other big brands do, too.
TYLER: The reality is you might save hundreds of dollars with a counterfeit carbon fiber bike, but it could cost you your teeth. For NPR News, I'm Jeff Tyler in Los Angeles. Transcript provided by NPR, Copyright NPR.