Colnago C50 cutup by Luescher

[zmalwo]

https://www.youtube.com/watch?v=61W6PG3kbmo&ab_channel=LuescherTeknik

I thought lugged bikes have much better construction but apparently not! These bikes are not meant to be ridden for decades for sure.

[Clean39T]

https://www.youtube.com/watch?v=61W6PG3kbmo&ab_channel=LuescherTeknik

I thought lugged bikes have much better construction but apparently not! These bikes are not meant to be ridden for decades for sure.

ProTip: watch all Luescher vids at 1.25 speed..

[tctyres]

ProTip: watch all Luescher vids at 1.25 speed..

Wow. That's the first ProTip that I thought was a ProTip. Kudos, Clean39T!

Leuscher sounds pretty normal at 1.5x, too.

[prototoast]

I thought lugged bikes have much better construction but apparently not! These bikes are not meant to be ridden for decades for sure.

The lugs and chaiinstays/seatstays are still molded, so would be just as susceptible to voids as any other molded frame. It might not be the finest craftsmanship, there's so much material at the joints because of the lugged construction that it just doesn't seem to be a practical risk.

The only failures I've heard of with these frames were from galvanic corrosion at the spots where there are alloy inserts.

[one60]

I've begun to wonder whether these videos provide any truly useful insight beyond identifying potential design flaws?

As I understand it, the majority of these frames have not failed due to voids or incomplete compaction or other perceived flaws.

Would the ride quality, stiffness or other parameter be different for a given frame with versus without such flaws?

Similar cut ups of venerated lugged steel frames would show incomplete brazing or poor penetration. But again, the failure rate is low and the effect on the ride quality is largely unknowable?

[jpw]

Isn't this a great opportunity for a brand to display the superior quality of their wares? Cut up a frame and show the world that there are no voids, no resin dry, no wrinkles, et.c., et.c.,

Tube to tube construction seems to be a more controllable technique, no?

[djdj]

https://www.youtube.com/watch?v=61W6PG3kbmo&ab_channel=LuescherTeknik

I thought lugged bikes have much better construction but apparently not! These bikes are not meant to be ridden for decades for sure.

No problem with mine, which is about 15 years old.

[oldpotatoe]

I've begun to wonder whether these videos provide any truly useful insight beyond identifying potential design flaws?

As I understand it, the majority of these frames have not failed due to voids or incomplete compaction or other perceived flaws.

Would the ride quality, stiffness or other parameter be different for a given frame with versus without such flaws?

Similar cut ups of venerated lugged steel frames would show incomplete brazing or poor penetration. But again, the failure rate is low and the effect on the ride quality is largely unknowable?

I don't think so. Perhaps on a failed or failure prone frame, THEN cut up and 'gee, look at THIS'. But as you mentioned, even with all the 'others', these frames don't fail and many sing the praises of this frame in terms of ride quality and longevity.

[wallymann]

agree. especially for older over-built CF construction, these cut-ups reveal stuff about slightly imperfect assembly. absent major issues, such observations are irrelevant to everyday performance and function.

this is not to denigrate luescher's work and knowledge -- he does good stuff and knows his isht!

I don't think so. Perhaps on a failed or failure prone frame, THEN cut up and 'gee, look at THIS'. But as you mentioned, even with all the 'others', these frames don't fail and many sing the praises of this frame in terms of ride quality and longevity.

[mastaliu]

I really don't know what to think of Luescher's videos. They are fascinating for sure and I learn about different carbon fiber molding techniques like bag vs EPS and what constitutes bad design. It seems that all of these frames come to the shop after crashes and failures and this can lead to all sorts of conclusions and fears from viewers. The C50 in the video was full of cracks and delaminations from some hits to the tubes. The galvanic corrosion at the bottle bosses is a feature of these frames after many years and certain conditions. It's an older design and carbon manufacturing and assembly technique that most likely could not address voids in the same way as modern methods but the construction was most likely overbuilt with materials at key areas to prevent failures. I have seen two C40 frames that came unbonded from the lugs but this must be exceedingly rare and they were two decades old and beat up frames with heavier riders. I have never heard of a Look 585 or similar having any issues or catastrophic failures. I would imagine that aging is something to consider with this sort of tube to tube construction and important to take a look the carbon forks on older frames. I dread the day when Luescher reviews one of the bikes I have but I wouldn't be able to look away!

[happycampyer]

Wow. That's the first ProTip that I thought was a ProTip. Kudos, Clean39T!

Leuscher sounds pretty normal at 1.5x, too.Agreed! Total game changer.

I think that it’s hard to extrapolate that one bad C50 means all C50s are bad. It’s a production frame, and some frames are going to be lemons. To jpw’s point, this is where boutique builders have a potential advantage. I have seen cutaways of Parlee and Serotta carbon frames, and the precision is incredible. It would be interesting to hear from Messers Crumpton, Lopez and other experts in the area who frequent here.

[earlfoss]

I appreciate his videos. In addition to the cut up work, he also comments on functional design elements that are good/bad. Case in point - the Cervelo S5 video where he shows just how bad the fork turn stop within the head tube was designed and how it can easily make your expensive new bike worthless even in a seemingly minor situation.

[roguedog]

Ya. I watched a few of his videos and they are interesting but slow. I feel like if I've watched one I've watched most of them.

I understand he builds bikes with carbon fiber. I think it'd be interesting to see a video how he overcomes these flaws in his construction. Or what is it in the process that would improve the faults. Maybe he already does this and i've just not watched enough.

[prototoast]

Isn't this a great opportunity for a brand to display the superior quality of their wares? Cut up a frame and show the world that there are no voids, no resin dry, no wrinkles, et.c., et.c.,

Lots of brands do this. Here's one from forum sponsor Pursuit Cycles that looks immaculate inside: https://www.instagram.com/p/B34bI9AlzJH/

Argonaut showed one off at NAHBS a few years ago: https://cyclingtips.com/2017/03/north-american-handmade-bicycle-show-live-tech-coverage/

Santa Cruz bikes has a cut up frame on display at their HQ in Santa Cruz, and there are plenty of other examples you can find if you search Bikerumor.

What's not always clear is whether these frames chosen to display are random samples or special models made to be cut up demos.


Tube to tube construction seems to be a more controllable technique, no?

The biggest advantage tube-to-tube construction has are simpler shapes. A roll-wrapped tube is easy to get void-free. A simple molded tube isn't hard either. Trying to mold a complex bottom bracket cluster, on the other hand, can be a challenge to get just right. But with all that said, any style of construction can be done well, and any style can be done poorly.

As a hobbyist who makes carbon frames, I don't have the resources for extensive engineering and testing, but I do have the luxury of just using more material. On a 700 gram frame, there's not a lot of margin for error. If I make my frames to be 1100-1200 grams, that's about 60% more material, which should make it robust to manufacturing imperfections (not that I try to do a bad job, and I have thrown out frames that haven't met my standards). The Colnago C50 is a ~1300 gram frame, so there's a lot of extra material to work with if something isn't perfect.

[Big Dan]

It's only fun when he is cutting up Cervelos.....

:cool:

[jemoryl]

I enjoy seeing that the Emperor has no clothes! The construction on the C50 and a recent Pinarello that he has cut up looks pretty sloppy compared to that of a Time and a Canyon(!). What were they thinking with the "B-stay" thing? One can only hope that Colnago has improved their processes since that example was made (maybe their collaboration with Giant helped?).

[Dave M]

Hard to know what to make of this. I bought a C59 once that had similar cracking in the white paint around the bottom bracket. I returned it and got my money back. But that experience does make me question the quality control. And the plastic bladder bag left in the chain stays on the C50 — c’mon dude. Really?

On the other hand, that C50 was one rough looking, unloved bike. And I have some doubts that was a genuine Colnago. But even if it were, they were pretty robust by reputation. I’ve not heard stories of unexpected failures on Colnago’s lugged frames of that era, although I don’t doubt they exist. I’ve got a C40 and an EPS, and they have been trouble free. The EPS might be my favorite of any bike I’ve ridden.

[jemoryl]

...... And I have some doubts that was a genuine Colnago.....

I don't think knockoff carbon frames were a thing when the C50 was in production - it is a more recent phenomena.

[vespasianus]

I've begun to wonder whether these videos provide any truly useful insight beyond identifying potential design flaws?

As I understand it, the majority of these frames have not failed due to voids or incomplete compaction or other perceived flaws.

Would the ride quality, stiffness or other parameter be different for a given frame with versus without such flaws?

Similar cut ups of venerated lugged steel frames would show incomplete brazing or poor penetration. But again, the failure rate is low and the effect on the ride quality is largely unknowable?

Actually, I think this video perfectly represents why bikes have the warranties they do. This particular bike appears to have multiple manufacturing defects that lead to cracks and other issues. However, it did not lead to catastrophic failure and most likely did not show up until the warranty was expired.

Personally, I think with a carbon bike - it might be useful to do a full carbon examination (ultrasound, etc) after a few years to make sure you don't have issues. I also think that carbon with cracks in certain places, is a lot stronger than we think.

[54ny77]

what, is he the ralph nader of carbon bike manufacturers?

and how many pro victories were done on a c50?

he's like "that guy"on a car forum who's crapping all over porsche or corvette or whatever engineering, pointing out how bad the chassis is, blah blah blah.

bet he's real fun at parties.

:D

[Spaghetti Legs]

I remember reading an article with pics 5-6 years ago about someone cross sectioning a Scott frame, showing its poor quality and comparing it to the excellent quality of a similarly cut Colnago. Go figure.

Moral of this I guess is you should cut your frames in 2 or 3 pieces before riding.

[mcteague]

ProTip: watch all Luescher vids at 1.25 speed..

:banana: Makes all the difference in the world! Kudos!

Tim

[texbike]

I've had several C40s and C50s over the years and have one of each now. None of them have had any issues, but almost all of them have had corrosion around the top tube cable guides and yellowing or cloudy clearcoats. They've been great riding bikes, but to be honest, I prefer my Ti bikes due to the significatly better build quality and lack of corrosion and breakdown of the clearcoat.

Texbike

[barnabyjones]

I watched the video and I think I missed the conclusion. Was that frame going to fail from the BB? And why didn't he review the fork? They never do, right?

[glepore]

15 y/o bike. Its not like they're failing in droves or have. Fake news.

[happycampyer]

what, is he the ralph nader of carbon bike manufacturers?

and how many pro victories were done on a c50?

he's like "that guy"on a car forum who's crapping all over porsche or corvette or whatever engineering, pointing out how bad the chassis is, blah blah blah.

bet he's real fun at parties.

:DHe’s more fun at 1.5x speed...

[dem]

My take-away from this videos is that carbon is really tough, and anything made in a modern carbon china/taiwan factory is just fine.

It has helped me be comfortable riding generic china framesets instead of spending $2000 on a name brand bike with pretty paint. :)

[jischr]

I stopped watching his vids. Opinions presented on a typical sample size of one. A frame/fork/component that failed/damaged/crashed. Meaningless to me. Cut up 10 frames of the same model year, better cut up 50. Catalog the issues and look for reports of failures that could have resulted from that issue. I'll keep riding my carbon Colnagos regardless of Luesher's opinon on a single sample. At 18 and 8 years old I expect them to last as longer than the riding time I have left.

[Hellgate]

Isn't this a great opportunity for a brand to display the superior quality of their wares? Cut up a frame and show the world that there are no voids, no resin dry, no wrinkles, et.c., et.c.,



Tube to tube construction seems to be a more controllable technique, no?Sure it is. Just cut up a dozen frames a choose the best for each area of the frameset.

I'm curious to see a few cut up military aircraft to see what those joints look like.

Oh, and my 40 year old Peugeot PX10 has the worst brazing know to man and is a wonderful ride.

[vespasianus]

Sure it is. Just cut up a dozen frames a choose the best for each area of the frameset.

I'm curious to see a few cut up military aircraft to see what those joints look like.

Oh, and my 40 year old Peugeot PX10 has the worst brazing know to man and is a wonderful ride.


Every single Boeing carbon components is examined in detail using a variety of methods and a single void is enough to dump a piece.