pivi

I am very concerned about carbon fiber parts and always check my bike thoroughly.

Mine is a 2010 Giant Defy 1. I was cleaning my fork today, and noticed these 2 black stains on the fork:




I did the "tap test". I lightly tapped the area with a coin, and I haven't noticed any weird sound. No difference on texture. Every time I notice a scratch in the fork, I use nail base (as the mechanic at the LBS recommended). So, the next photo may look worse, but it's because of the nail base. The surface still looks smooth, like the previous photos. Those were taken after this one:



Is this fork still safe to ride? The bike has about 700 miles, and never raced and never crashed.

Thanks in advance.

nwbikeman

Should be fine with the tap test as carbon is 2x stronger thanmost aluminum. Also if you see something questionable (Worse than this) press on the area in question and see if you can flex it or feel a soft spot, which would then be damaged. It takes a lot to damage carbon. You won't crack it by just riding along.don't be afraid.

rekmeyata

It doesn't take that much to damage carbon, in fact they've been having more carbon failure then any other material, but that will cause a huge argument so that's all I'll say about it. Personally I would take it to an LBS and have a pro look at it, it shouldn't be doing that, whether it's safe or not can't it be told by a photo. For peace of mind take it in.

JohnDThompson 

The top layer is not structural but cosmetic. If that's all that is affected it should be fine.

HillRider

Is that because these days there IS more carbon than any other material?

rekmeyata

On the surface that would seem true, but when you go and figure the percentages of CF vs others then you discover the failure rate is higher percentage wise. At one time steel was all there was and so that's all that failed, does that mean steel was bad? No. But now you have all sorts of material, and percentage wise CF based frames and forks are failing at a higher rate...ESPECIALLY Chinese made CF components. The percentage of Chinese made CF component failures is alarming even among high priced Chinese made components.

And I don't think the OP should base their decision not to have it looked at by someone saying it's ok ride and forget about it. Pictures don't always tell a accurate story vs being there and seeing it live. I personally don't think it's a problem, but I won't stake the OP's physical well being on that statement, I would tell him to take it in and make sure. Then even after you take it and it's ok'd to ride...keep an eye on for further problems.

StanSeven

What's your source of data?

You statements are so precise, I assume you have proof of them.

keisatsu

Lol, you sound like Fox News "Here are FACTS! They are facts because I say so!!!"

rm -rf

If I worked at the LBS, I wouldn't give an opinion, unless it was just an obvious surface scratch. If I OK it now, and it breaks later, then what happens?

Would even a "pro" place like Calfee, that repairs broken carbon bikes, want to give an opinion?

pivi

I just took the bike to the LBS (a Giant preferred dealer) today. I noticed those stains while cleaning the bike, in my house, last night. Under sunlight the stains were almost impossible to find, so I used the Cateye headlight to find them. The mechanic said the same thing: "don't worry, it's cosmetic. These forks are pretty strong. I never saw one of them break out of nowhere, only if you crash them".

I think I've been reading that Busted Carbon blog so much... that's real scary.

I already got the carbon seatpost on this bike replaced. It started to crack in less than 2 months use (although I don't put much pressure on the bike, I'm a 6'3", 250lbs rider). Interesting is the fact that Giant itself, not the LBS, didn't give me a similar one - they sent me an aluminum Easton Havoc instead. To be honest, I feel much safer with this seatpost, it works perfectly so far, more than a year after.

Nerull

I hope no one shows you all the pictures of aluminium frame failures.

Seatposts usually crack because they've been overtightened.

531phile 

It's just your local carbon hungry vampire. Nothing to worry about.

rekmeyata

Calfee will look at for a fee, I think it was $150 plus shipping plus you have to strip the bike of all components before shipping. But supposedly if you take the bike to an LBS that sells Giant as in this situation and the LBS cannot tell if it's ok, then they can make arrangements to either have it sent to Giant for a look, or have a Giant rep come and look at it. This service is usually done for free by the manufacturer of your bike whereas Calfee will charge.

rekmeyata

Unfortunately just as with steel and aluminum there is no "proof" on the web; but if you ask a bike shop that has been around for 40 years they will tell you what I said because I had several LBS's tell me what I related to you, such as Aaron's Bicycle Repair in Seattle who said this: It's just one man's opinion, but he's in a position to know. A fellow named Aaron Goss, president of Aaron's Bicycle Repair, Inc., in Seattle, wrote to trade magazine Bicycle Retailer and Industry News to express concerns about the ubiquity of carbon fiber cycling products.

Goss is an admitted carbon cynic. He says flat-out, "Our view has always been that carbon fiber's disadvantages outweigh its supposed advantages."

In the category of food for thought, here's some of what this professional mechanic wrote to his peers in the cycling industry:

"We are seeing an exponential increase in damaged and broken carbon fiber parts, forks and frames."

"Carbon should be reserved for race use only. Everyday bikes should be metal."

"We find it reckless that everyday folks can buy ultralight carbon fiber parts that they assemble themselves and then ride on rough roads."

"I would say, conservatively, one in 10 [carbon] seatposts is damaged from improper installation."

"Customers don't like hearing that they need a new handlebar or a fork after a crash."

"Check out the Busted Carbon blog for JRA [just riding along] broken carbon: https://www.bustedcarbon.com."

"We have created a web page to educate our customers: https://www.rideyourbike.com/carbonfiber.shtml."

"Steel trumps all other materials when you factor in durability, repairability and recycleability. It is pleasing to see the industry turning again toward the greenest of all frame materials."

If you want CF recalls that's on the internet such as: ---Product recall: About 200 Easton EC90 Zero seatposts. The carbon clamp atop the Chinese-made seatpost can crack, posing an accident hazard to the rider. The EC90 Zero post is black with red and gray graphics. Bikes with these posts were sold at Turner Suspension Bicycles, Ibis Cycles and Security Bicycle Accessories retailers in the U.S. from April through August 2010 for $150-$200. Owners should immediately stop riding the bicycles and contact an authorized Easton Sports dealer for a free replacement clamp. More info on the Easton website.

--Product recall: Carbon forks on certain Felt F-series road bikes. Affected models are the 2011 Felt F3, F4, F5, F5 Team and F75. Owners should stop riding these bikes and contact a Felt dealer for a replacement fork. Felt says that although current forks meet CPSC standards and no forks have failed, its in-house testing has detected substandard performance. "Our protocol is to test carbon frames and forks at random from our OEM carbon factory assembly lines," explains Felt company president Bill Duehring. "After testing a cross-section of early production forks we are simply not satisfied." Replacement forks will come from several manufacturers, including Enve, Easton and 3T. Contact Felt Dealer Support at 866-433-5887 or dealersupport@feltbicycles.com.

--Widespread bicycle recall due to faulty crank
A Washington-based bicycle component manufacturer is recalling 9,300 bicycles that were outfitted with a faulty crankset that can break, causing falls and injuries.The recall involves 21 different bicycle models from 8 bicycle brands (see list below) that were sold between February and October this year.
The US Consumer Protection Agency urges owners of the listed bicycles to stop using them immediately and take them back to the dealer for inspection and free replacement of the faulty crank arm. Eleven breaks have been reported, and two injuries.
The importer, Full Speed Ahead of Woodinville, Wash., issued the recall for its BB30 Gossamer crankset installed as standard equipment. The cranks were manufactured in Taiwan by TH Industries.

The cranks involved have two drive gears (triples are not involved in the recall). They are painted either black with "Gossamer" printed in white on the arm or white with "Gossamer" printed in black on the arm. The crank arms at fault have serial numbers beginning with either 10B, 10C, or 10D on the backside of the arm, near the pedal threads. If the fixing bolt on the non-driver crank arm is over-tightened, the bolt shoulder can crack or break, causing the crank arm to fall off the bicycle.

The bicycle models in the recall are:
Bianchi
2010 Sempre Ultegra
Cannondale
2010 CAAD9 5, CAAD9 5 Feminine
2010 Six Carbon 5
2010 Slice 4, Slice 4 Nytro, Slice 5
2010 Synapse Carbon 4, Carbon 4 Feminine, Carbon 5
2011 CAAD10 5 105, CAAD10 5 105 Feminine
2011 Slice 5, Slice 5 Womens
2011 SuperSix 5 105, SuperSix 5 105 Womens
2011 Synapse Carbon 4 Rival, Carbon 4 Rival Womens, Carbon 5
2011 CAAD8 5 105
2011 CAADX 105 Cyclocross
Felt
2011 F75
2011 F75X
Fuji
2010 ACR 1.0
2010 ACR 2.0
2010 ACR 3.0
Quintana Roo
2010 CD.0.1
Litespeed
2010 C3
Raleigh
2011 RX 1.0
2010 RX 1.0
Scattante
2010 CFR Comp
More information
For additional information on obtaining a free replacement non-drive crank arm, contact Full Speed Ahead toll-free at (877) 743-3372 between 9 a.m. and 5 p.m. PT Monday through Friday, via email torecall@fullspeedahead.com, or visit the firm’s website atwww.fullspeedahead.com (pdf)

Nerull

You forgot to mention the recent Salsa handlebar recall - they could break in half while riding - oh wait, those were steel.

Also...your last recall is for an aluminium crank. Gossamer is the low end model, no carbon to be found. Oops.

And even if it was a carbon crank, I'm not sure how "The bolt can break if overtightened, letting the crank arm fall off." would be the carbon's fault. They don't make the bolts out of CF, you know.

rekmeyata

Oh wait, Salsa doesn't make steel bars...they only make aluminum...oops.

Nerull

Oh, I misremembered. It was stems, not bars.

https://www.cpsc.gov/cpscpub/prerel/prhtml11/11083.html

vredstein

"...they've been having more carbon failure then any other material, but that will cause a huge argument so that's all I'll say about it."

Talk about sudden and catastrophic failure...

JohnDThompson 

Check the bike racks at any university and report back on the numerical superiority of carbon fiber bikes.

HillRider

True, but I was refering to bikes ridden by "enthusiast" and competative riders using up-scale components, not strictly derpatment-store quality utility bikes. Buy your population sample you could also conclude that only a very small fraction of bike riders wear helmets or use clipless pedals or use drop handlebars.

Nerull

By that sampling I would conclude that the majority of bikes are falling apart and in disrepair.

JohnDThompson 

Both your statements recognize that the vast majority of bicycles out there are not well-maintained carbon fiber models. How many non-carbon frame failures are there? Are those failures proportionately similar to the number of failures in the carbon frame population?

rekmeyata

But again those stems are aluminum not steel...oops again.

Nerull

Well, I guess I have to read this to you really slowly.

"This recall involves all CroMoto S.U.L. 25.4 and 26.0 threadless handlebar stems and all CroMoto S.U.L. 26.0 quill handlebar stems sold as individual aftermarket units after April 1, 2010."

CroMoto is Salsa's name for their parts made of CroMoly. CroMoly is another name for...41xx steel.

Let me know if that was too complex for you.

rekmeyata

Yes, that was too complex for me, thanks for clearing that up.