How to examine a cabon fiber frame.

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Anonymous's picture

"There I was, riding along, having a great day on my one-of-a-kind carbon fiber dream bike. Then, KAPOW, I get smashed from behind by a car and tossed into never never land. Upon initial inspection, by body was okay. Then, upon close up, they found internal damage. I'll be fine. Hmmmmm. My bike, my frame, upon initial inspection, my beautiful bike was okay. Any one know how I can check out the frame to be sure? I've heard Calfi has this device that can kind of X-ray the frame. But, Calfi says that's make believe - that there is no such thing. They can give it a ""stress test"" and it's a good test, but not fool proof. Seven can do pretty much the same.

Anyone know of or hear of a way to examine a carbon fiber frame with certainty?

Anonymous's picture
Claudette (not verified)
Are **YOU** OK????

Holy moly, that is scary! Is everything on YOUR body all right?

I know nothing about checking your frame but would there be some sort of stress test?

Take care of yourself.

Anonymous's picture
Christy Guzzetta (not verified)

C'mon Claudette . . .
you know only the good die young - I'm fine!

Anonymous's picture
Bill Vojtech (not verified)

"Define ""young""."

Anonymous's picture
Keith (not verified)

Christy, Sorry to hear about this. I have been riding carbon a long time, from my Specialized Epic to Giant to Cervelo. As long as there are no gouges or chips, the frame should be fine. Surface scratches are okay, but do check regularly to make sure that they don't spread. I always check my bike very carefully after every ride, no matter what the material, to be sure everything is ok. I never ride carbon bars or stems. It is harder to determine their structural integrity after a crash. To be safe, if they hit the ground hard, trash them. Nothing worse then going down because of a bar/stem failure.

BTW, this past April my carbon frame cracked going over some railroad tracks. The down tube separated from the head tube. It was a lugged carbon tubed frame. I was still able to ride the frame home, slowly, watching the tube move in and out of the lug as I rode. Five miles and 1 1/2 hours later I made it. The frameset ended up being recalled from the manufacturer. My new frame is monoqocue. Carbon these days is a lot stronger then the carbon tubed bikes of old.

Anonymous's picture
Christy Guzzetta (not verified)

"My frame is monoqocue (is that how you spell ""monoqocue""?). And I did go over it with a magnifying glass. Three other people I trust did as well. I'm optimistic it's fine. Just want to be as sure as I can.

I'm actually thinking this is good karma. . . me and my bike, run down, wounded, yet we'll ride together again. That must be good karma.

Good karma, lousy driver."

Anonymous's picture
Keith (not verified)

"Ooops, ""monocoque"". Typo!"

Anonymous's picture
Christophe (not verified)

i don't think you'd want to stress test it- any undue stress would be a bad thing IMO... however, inspect it throughly for cracks. if you find any, the rule of thumb is the following: if you can stick a razor blad in the crack, you need to get the bike checked out.

Anonymous's picture
David Schlichting (not verified)

One of the seminars at last week's Interbike was put on by Cervelo and FSA and covered shop issues regarding CF bikes and components. Naturally, their message and the advice to dealers was CYA based and wisely so.
According to the presenters (one of whom was the well known Rick Hjertberg from FSA) there is no X-ray or other scan type test to check for failures.
They are used to getting frames from customers who have had incidents and can give a somewhat more educated once-over. Cervelo will certainly encourage this, but reverts to the paragraph above.
Short of this, best advice is to visually scan the surface of the frame very carefully looking for undulations which would suggest delamination. This can then be confirmed by tapping along the area with a coin and listening for a change in tone (dull) which would indicate a delimination.
For frames which are lugged/glued (i.e. not monocoque) the presenters say there is no test to check for internal failures the lamination of these joints.
Hope this helps.
Good luck

Anonymous's picture
An anonymous cow! (Christian Edstrom) (not verified)

Short of destructive stress testing, there is no way to be 100% certain about the integrity of the frame.

So if that's your AXM, I think your only reasonable recourse is to treat the bike as trash and get a replacement from the automobile driver's insurance company.

I know this might sound outlandish to some, but it's a mega-buck frame, and there's just no way to know. I draw the following analogy - we use carbon fiber HANS devices when we race cars to prevent basal skull fracture. They are designed to withstand a 70g frontal impact (which is basically impossible to achieve short of a NASCAR into a concrete wall). Nevertheless, after even a minor accident, they are replaced, at a cost of $1200 each. Because despite the wonders of carbon fiber, you just never know.

- Christian

Anonymous's picture
Evan Marks (not verified)
Look on the bright side

You're ok, right? (Ouch.)

The bike can be replaced.

Anonymous's picture
Christy Guzzetta (not verified)

"No, no, no - the bike can't be replaced. It was a limited edition run. It is irreplaceable.
Me. . . .I'm getting a brain transplant, a new leg, and a brand new head of hair. I can be fixed, the bike is irreplaceable!
I was lying there on the ground wrything (sp?) in pain, crying, ""My back is killing me . . . how's my bike?"" Screaming, ""My leg, I think it's broken . . .how's my bike?"" Then this guy comes over to assure me I'd be okay, the ambulance is on the way . . .I don't care, ""How's my bike?"" I want to know. The guy tells me it looks okay. ""Yeah? Tell me what you know about bikes. Are you sure it's okay? Do you know about these things? Do you know what carbon fiber is? Do you even know who Eddy Merckx is?"" The guy proceeded to leave me, just left me there on the side of the road, the vultures circling above.
The bike, I'm fine, this about the bike! There are doctors to look over me, drugs to treat me, rehab to make me better. But my bike. . . . . ."

Anonymous's picture
Evan Marks (not verified)
Irreplaceable? One-of-a-kind?

Maybe you should get something less exclusive. Something like . . . steel.


Anonymous's picture
don montalvo (not verified)
this is why i chose titanium...

...i've been through enough carbonfiber frames to know how delicate they are. all jokes aside...what internal damage was found (you) and did you contact the merckx factory to see what their policy is on frame replacement or repair?


Anonymous's picture
Serge Utin (not verified)
That's really scarry! Were you riding alone or with a group?

Glad you are OK.

Anonymous's picture
bill (not verified)

I have a calfee and a kestrel. both have their share of chips and small gouges. Dealers and co's have looked them both over and felt they were ok.

The calfee has more chips than the kestrel as I bought it well used. Before I bought it I send detailed pics to Calfee. They said the frames where chips and lines and such are scary are those that are hollow inside like eggshells. They get their strength from the surface. They said the calfee frames were not like that and had plenty of carbon structure internally. Not knowing your bike, I recommend sawing it in half to confirm. If it's solid, you're good to go.

Anonymous's picture
Robert Shay (not verified)
Informative article on Carbon Fiber

I ride a trek Madone carbon fiber bike. I believe that a carbon fiber frame is made of carbon fiber cloth and epoxy. A hairline crack in the epoxy and you're sol. I carefully inspect my frame in the sunlight every time I wash it. Trek provides the following article on carbon fiber care:

Sorry to hear about your accident. To be hit from behind is one of the worst fears I have - since I can't control it. Is there anything we can learn from your accident to prevent it from happening again?

Anonymous's picture
Josh (not verified)


That accident sounded scary, but its great to hear that you are ok. All the best for 100% recovery.

You had to know that CF frames are disposable! Easy come, easy go! Just strip off those nice Campy doo-dads and stick em' on the next one!

(The night before I got my CF frame I had a dream that I brushed against a post on a two minute test ride, and the frame folded in half. I studied the broken tubes and observed that they were made of trash can liner plastic filled with styrofoam. After I woke up I told the dream to my doctor, who immediately adjusted my medications).

Is there any truth to the rumor that at the emergency room you demanded that the radiologist x-ray the frame before x-raying you?

Anyway, I have nothing constructive to add, because I know nothing compared to the others who have posted here.

Best regards,

Anonymous's picture
Christy Guzzetta (not verified)
Thanks !

Just wanted to thank you all for the great input.
You are a knowledgeable group, you took the time to share some of that knowledge, you helped me a great deal, taught me alot.
I am grateful, thank you.

Anonymous's picture
Guy (not verified)
Carbon / Cervelo Recalls About 650 Frames


This is NOT to point out the weakness of Cervelo but the weakness of all carbon fiber. Ironically, Cervelo's advertising blitz during the '06 Tour de France emphasized their superior carbon technology & strength, even showing simulated crashes in their ads. Many racers use their carbon frames for 1 year (or less) & replace them; of course, they get great deals on their frames for promo that we, the consumer, will buy them at full price. I know some racers on a NY team & they got deals on carbon frames from two bike companies -- the team captain & mechanic have told me every carbon frame gets trashed after one racing season!

CPSC and Cervelo Recall 650 Carbon Fiber Bikes and Frames

OCTOBER 03, 2006 -- BETHESDA, MD (BRAIN)—The U.S. Consumer Product Safety Commission and Cervelo are recalling about 650 Cervelo carbon fiber bicycles and bicycle frames due to the risk of the frames loosening or separating. The recall includes 2005 R2.5 model bicycles with serial numbers higher than R251700.

The model and serial numbers are printed on the bicycle frame tubes. The frames have a clear coating over the carbon fiber and either red and white or blue and white ""Cervelo"" decals on the seat, head and down tubes. Authorized Cervelo retailers nationwide sold frame sets and bicycles with these frames from December 2004 through May 2005.

The bikes were manufactured in Taiwan. Consumers should stop using these bicycles with the recalled frames and contact Cervèlo to receive a free replacement frame. For more information, call the company at (866) 296-3137 or click here."

Anonymous's picture
Robert Shay (not verified)
Carbon Fiber frames

"Read about the Cervelo recall, checked the website, looked at the framset. Looks like bonded carbon fiber tubes to the headset that is causing the problem.

Personally, I prefer a full Carbon Fiber frame (no bonding points) - Madone from Trek. It is very stiff, light, and easy over bumps. I ride about 6,000 miles per year in a combination of 40 mile rides and 110 mile rides. The frames stiffness translates into direct power transfer from the pedals to the wheels (read: no frame flex) - great for long rides and hills. I love this frame. I have 3,000 miles on it now. Trek provides a lifetime warranty on their frames as long as you are the original purchaser. Cervelo also provides a lifetime warranty. Neither of these companies would still be in business if there was ""a weakness of all carbon fiber"".

The Discovery team retires frames after every race season too. So what. My friend (a team sponsor) is sometimes fortunate enough to get one. He rides it often. It looks and rides great. I'm fairly certain they wouldn't give the principal from a title sponsor a weak frame to ride/train on. There are many great frame materials available today - IMHO carbon fiber is one of them."

Anonymous's picture
gOmer (not verified)

"Maybe the new models are different but the carbon Treks were always made from bonded tubes.

BTW, this is a good article from the Calfee site about carbon frames:"

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