interesting perspectives on carbon fiber bike design, manufacturing, repair, etc.

[CSTRider]

Carbon fiber - the truth! (https://www.youtube.com/watch?v=-qsLYlVWkbQ)

(warning - the first 15 seconds or so are weird ...)

[45K10]

Carbon fiber - the truth! (https://www.youtube.com/watch?v=-qsLYlVWkbQ)

(warning - the first 15 seconds or so are weird ...)

Yeah that first bit was weird but the rest was quite interesting
Thanks for posting

[ultraman6970]

good video.

[bicycletricycle]

that repair guy has some more videos that are interesting. the dudes interviewing him seem to be starting from zero.

[parris]

I've seen several of his videos. One of the earlier one's has the crash damaging his frame and had him to go to the repair guy. From what I remember he was in a group ride where a tourist not use to driving on the left side of the road made a wrong turn and there was a pileup. Several guys were hurt including the host with a broken wrist.

One of the other videos that's cool with the repair guy is that he shows a number of frames that he's sawed down the middle. He goes into some cool explanation of improvements in the manufacturing process as the factories have learned throughout the years. Neat stuff.

[Black Dog]

Very good and technically spot on. Reminds me of why I cringe when I see someone riding a no name carbon frame bought on Alibaba.

Here is his take on Carbon wheels: Part 1 (https://youtu.be/ET1jRVynOBA) and Part 2 (https://youtu.be/bFdG2NgIc7s)

[m_moses]

I follow that dude on Instagram. He often posts photos of the frames or parts he's repairing or deconstructing. Interesting stuff.

http://instagram.com/luescher_teknik


Sent from my iPad using Tapatalk

[bigman]

Yeah

[Pastashop]

I'd be very very curious to know what the failure rate for carbon frames and components is... Likely it's a closely guarded secret for the component makers, but shouldn't the bike community organize itself and post pictures + descriptions of failed components and circumstances leading to the failure?..

(There used to be a database of broken components, including cranks, with attendant info... Kind of important for failures that could result in serious injury – a pedal eye hole breaking can dump you into traffic, a steerer tube failing can spell major reconstruction surgery...)

[cadence90]

I'd be very very curious to know what the failure rate for carbon frames and components is... Likely it's a closely guarded secret for the component makers, but shouldn't the bike community organize itself and post pictures + descriptions of failed components and circumstances leading to the failure?..

(There used to be a database of broken components, including cranks, with attendant info... Kind of important for failures that could result in serious injury – a pedal eye hole breaking can dump you into traffic, a steerer tube failing can spell major reconstruction surgery...)

Yesterday I messaged the seller of this Deda Forza stem (http://www.ebay.com/itm/182425613183?ul_noapp=true), politely saying that maybe they didn't know but that that exact stem had been completely recalled (Google Deda Forza stem recall), because of documented failures, and that perhaps this should be somehow referenced in the listing.

A few hours later: "Thank you! Will fix that right away!"

As of today, of course, absolutely no change in the description at all. :rolleyes:

I suppose a database of some kind, listing for example all recalls, would be useful. Most sellers would probably not read it or respect it, but at least conscientious buyers could.

Certainly, continuing to list a known defective stem with no warning (let alone just not selling it, period), after someone in the bike community has reached out, is complete bull****. :mad:
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[Pastashop]

Yesterday I messaged the seller of this Deda Forza stem (http://www.ebay.com/itm/182425613183?ul_noapp=true), politely saying that maybe they didn't know but that that exact stem had been completely recalled (Google Deda Forza stem recall), because of documented failures, and that perhaps this should be somehow referenced in the listing.



A few hours later: "Thank you! Will fix that right away!"



As of today, of course, absolutely no change in the description at all. :rolleyes:



I suppose a database of some kind, listing for example all recalls, would be useful. Most sellers would probably not read it or respect it, but at least conscientious buyers could.



Certainly, continuing to list a known defective stem with no warning (let alone just not selling it, period), after someone in the bike community has reached out, is complete bull****. :mad:

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I hear ya... 'been tempted to do this for so many "For Sale" postings. But I get that even for non-crabon components. (Wheels that use radial spoking with J-bend spokes tend to be a flange failure waiting to happen... Octalink BBs... any non-sleeved handlebar whose torque history you don't know... but maybe I'm too paranoid :-)

[sitzmark]

Yesterday I messaged the seller of this Deda Forza stem (http://www.ebay.com/itm/182425613183?ul_noapp=true), politely saying that maybe they didn't know but that that exact stem had been completely recalled (Google Deda Forza stem recall), because of documented failures, and that perhaps this should be somehow referenced in the listing.

A few hours later: "Thank you! Will fix that right away!"

As of today, of course, absolutely no change in the description at all. :rolleyes:

I suppose a database of some kind, listing for example all recalls, would be useful. Most sellers would probably not read it or respect it, but at least conscientious buyers could.

Certainly, continuing to list a known defective stem with no warning (let alone just not selling it, period), after someone in the bike community has reached out, is complete bull****. :mad:
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He shouldn't "reference" the recall, he should take the item off eBay. Craigslist and all other resale venues have the same policy. Two reasons ... 1.) it is a violation of eBay's rules to sell anything being actively recalled, 2.) it is illegal (US law) to sell (or otherwise transfer ownership of) anything actively recalled by CPSC unless the the proper corrective action has been taken.

One of those things where there just aren't enough resources to monitor compliance and general public knowledge/acceptance of the rules is minimal. https://www.cpsc.gov/s3fs-public/ResellersGuide_0.pdf

Technically eBay has a responsibility to prevent listing of recalled items, but that's almost impossible without a mechanism that requires part numbers and serial numbers to list. Even then many items aren't serialized. eBay vests responsibility with the seller to keep recalled products from being listed and theoretically will take action if the company discovers a violation of their policy.

[cadence90]

He shouldn't "reference" the recall, he should take the item off eBay.

Of course. I completely agree. Thanks for your description of the legal issues/policies. I simply gave the seller the benefit of the doubt yesterday, hoping that he/she would in fact delete the listing..

A recalled stem is no joke, and I have seen photos of those cracked Forzas. Something like that failing could be potentially fatal. I couldn't believe the seller would simply do nothing, and apparently not care.

So just now I went through the (very straightforward, actually) eBay process:
Report Item
Report Category: Prohibited and restricted items
Reason for Report: Other prohibited or restricted items
Detailed Reason: Recalled items

Done. The seller must have no conscience at all. I hope eBay deletes the listing, and does not permit a re-listing.
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[oliver1850]

Good that you saw it and reported it, not to mention being aware of the recall in the first place. Of the thousands of bike parts that I've handled I'm not aware of any that have been recalled, but I'd guess some of them have been. The only ones known to be prone to failure are NR/SR cranks, but I don't know if they were ever recalled.

[oldpotatoe]

I'd be very very curious to know what the failure rate for carbon frames and components is... Likely it's a closely guarded secret for the component makers, but shouldn't the bike community organize itself and post pictures + descriptions of failed components and circumstances leading to the failure?..

(There used to be a database of broken components, including cranks, with attendant info... Kind of important for failures that could result in serious injury – a pedal eye hole breaking can dump you into traffic, a steerer tube failing can spell major reconstruction surgery...)

http://www.bustedcarbon.com/

https://www.reddit.com/r/bustedcarbon

[Pastashop]

http://www.bustedcarbon.com/



https://www.reddit.com/r/bustedcarbon


Yup... scroll down a handful of entries and see "Trek asploded: I was not there when this happened but this is the story as it was related to me. She spent a few days in the hospital over this. On a normal ride with friends and frame let go. She obviously went down and was injured but not severely. She says it just plain let go in the middle of riding, There as no impact or crash involved. From the look of the front end of the bike I have to say I believe it."

But the shock value isn't what we should be after. Rather, some sort of systematic cataloguing and analysis of frequency of occurrence and circumstances of the failure possible causes...

[R3awak3n]

this was really interesting. I also liked the video of his opinion on carbon rim brake clinchers (where he says he would never ride)

[Mr. Pink]

Fascinating.

Sure, he's a carbon fan, because he knows them very well, and could probably recognize a faulty frame before riding one, but, after watching that, I'll stick to my steel, thank you, confident that it won't fail in a catastrophic way at the worst time.

[Black Dog]

It would be very interesting to know the frequency of actual JRA failures. I would assume that it is very low, however, catastrophic failures of a certain type that almost certainly lead to serious injury should be zero. Problem is that this would add a few 100 grams to a carbon frame and the marketing dept would crap thier collective pants. We know that carbon can be made to be very strong but frame makers are constantly lowering the safety margins when they reduce weight. Since the production processes are not perfect they should be building in a healthy bit of redundancy but I suspect that they are not. I am sure most designs are very robust when the frames are built exactly to spec with very few flaws, however, how many builders are compensating for expected flaws due to production variables that are not fully controlled? This is not an anti carbon position at all just concern that manufacturers are not engineering for the expected unexpected. This is a common practices in many fields.

[Bob Ross]

Reminds me of why I cringe when I see someone riding a no name carbon frame bought on Alibaba.

Pretty sure I've told this story here before, but it bears repeating:

3 or 4 years ago I was on a cycling tour of Sardegna. One of the other cyclists had a very attractive but conspicuously anonymous carbon frame. I asked him who made it. I forget what his answer was, either Bikes Direct or some equally suspect off-brand. I gave him the quizzical hairy eyeball and asked as nonchalantly as I could "How is it?"

He said "It's great, what's not to love? If it explodes, I can buy another one. If that one self-destructs, I can buy a third one. If that one disintegrates mid-ride, I can buy a fourth one. I can do that five or six times and I still won't have spent as much on a frame as my son spent on his Cannondale!"

The irony was, on day six of this tour, his no-name carbon frame disintegrated mid-ride! (Admittedly not entirely the frame's fault: A mis-shift during a long descent caused his rear derailleur to swing around clockwise and completely saw through the seatstay.)

[dem]

Amusingly, if you watch all that guy's videos, he has one where he dissects an ENVE rim and a generic China rim, and the ENVE had voids and inconsistent layup thickness.

Since almost all this stuff is built by the same factories using the same techniques, I am deeply skeptical you're getting anything other than brand and warranty with expensive carbon.

Where does that leave the consumer? I've no idea. I ride both - I have a Parlee and a Generic Chinabike. I also have two sets of China wheels (disc only.. I would never ride carbon rim brake clinchers of any brand.) Maybe there needs to be something similar to the UL for carbon QC!

The level of non-crash JRA failures across all Carbon seems remarkably low, so there must be a lot of margin of safety in most designs.

[R3awak3n]

Amusingly, if you watch all that guy's videos, he has one where he dissects an ENVE rim and a generic China rim, and the ENVE had voids and inconsistent layup thickness.

Since almost all this stuff is built by the same factories using the same techniques, I am deeply skeptical you're getting anything other than brand and warranty with expensive carbon.

Where does that leave the consumer? I've no idea. I ride both - I have a Parlee and a Generic Chinabike. I also have two sets of China wheels (disc only.. I would never ride carbon rim brake clinchers of any brand.) Maybe there needs to be something similar to the UL for carbon QC!

The level of non-crash JRA failures across all Carbon seems remarkably low, so there must be a lot of margin of safety in most designs.


this is not true for enve. They build their wheels in the US still and the tech behind is is very different than asian carbon. The spoke holes are molded instead of being drilled which makes for a much better rim.

enve forks and probably stems/seatposts are made in asia so with these parts you may be right (but QC is higher buying enve than just buying some carbon bars off ebay)

[dem]

this is not true for enve. They build their wheels in the US still and the tech behind is is very different than asian carbon. The spoke holes are molded instead of being drilled which makes for a much better rim.

https://www.youtube.com/watch?v=A8fsKeQwplg

Then it proves you can make crappy carbon in the US, too. Lots of caveats beyond voids and inconsistent thickness.. but sure isn't super inspiring.

[aaronf]

Does anyone know of anyone in the US (or Canada even) known to be doing the same level of ultrasound inspections as Raoul on questionable carbon frames/forks/rims/etc?