I own a Trek 5200 from 1998. I raced that frame from 1998 - 2009 I officially retired it only because I I wanted to try out a Madone. I still own that 5200 today and it's just as stiff as it was brand new. I don't race it anymore but I do use it on tours rides, fundraisers, and riding to work. It doesn't just sit. I do keep it inside my house when not using it. It is well cared for as in maitained. The frame doesn't feel dead it's 26 years old I estimate over 200,000 miles on it and it's just as if not faster then most modern bikes
Yeah and thats quite obvious why. You have so many different situations and factors playing a roll for everything in our world. Thats why i dont trust people who say its like this abd nothing else.
@@hondasaurusrex6998 Until someone gets hurt, or dies, as a result of a decision made without taking all the relevant factors into account. I guess that you are not an engineer then? ;)
This is such great content. In a world where the majority of YT videos is an ad for something it's just great to see plain informative content. Thanks!
My take out is that Composite Carbon Fibre has as many positives as negatives and that while it is massively strong, the way it is applied to bicycles makes it extremely delicate and in fact less robust than metal frames from a reliability and longevity point of view. My worry is that while it is strong while new, degradation from continuous vibrational amplification is known to weaken the very best polymer substrates that form and bind the Carbon fiber matrix. Basically even the smoothest road surface creates vibration and combined with the intermittent shock forces of striking the occasional pothole obviously will accelerate micro degradation untill catastrophic failure. This may be an unpopular opinion but is based on the sad fact that everything has a lifespan and nothing lasts forever 😕
Finally a proper engineer on RUclips and not a self proclaimed expert trying to gain RUclips followers and set a anti bike industry narrative to gain sales and support for the brands they represent, whilst telling everyone you should not do excactly what they are doing. Or implying excessive force damage(a crash) is somehow defective manufactoring. This is very insightful
Ollie - I love these videos of interviewing cutting edge scientists. I would ask not only about aluminum and steel, but titanium as well when you are able to perform the second interview. I certainly would like to see more videos like this one!
Aluminum frames will crack over time as metal is crystal. How long depends on design and heat during construction. I had a road bike fail after 8 years of almost daily use. I also have a mtb frame that's over 10 years old that has not cracked yet and it is used a few days a week on trails without Jumps. I would not worry about steel frames unless it's rusted our crashed hard.
Been running the same Chinese frame for over 9 years on a hard tail XC race bike. I however have recently moved to more trails riding and have taken that bike through more than it should have ever been through. Still holding up :)
Hey do tell me about the frame, brand and the type of riding you did! I just restored a now 12 year old (maybe 13) scott scale xc frame with reinforcement fibers from an f1 vendor... I've also had the frame x-rayed by a friend who's willing to do it for a fare price at different levels, came back safe...anyways I'm converting it to gravel but still want do hit a few mountains on it haha we'll see🤷 also I've riding prior to it's new fabrication updates with no issues....but the whole idea of the reinforcement was because it was old; so like mentioned in the video "needed a touch-up".
I own a carbon sprint kayak and a carbon wing paddle that i still paddle regularly.The sprint kayak is 22 years old and the paddle 25. Don't be a fool, don't believe what industry says.
Thnx Ollie, great content. (I was getting fed up with all the sponsored bits, it feels good to not have to be cynical about a topic because of the segment being sponsored)
Wow, now this is an awesome content from GCN! Understand GCN can't be producing these type of contents all the time but keep it coming! Good one GCN, good one Ollie and thanks to the experts too for their insight! Hoping for a part 2 n maybe 3 from those polymer experts and then about the other materials like aluminium, steel and especially titanium!
Here’s my takeaway: Thinking about carbon failure is energy draining which robs us of watts. Which then prevents Ollie exceeding 1000 watts. Now off to that video.
One of my favorite Tech videos to date. Please do one for metal frame materials. I have a particular interest in titanium and stainless steel and would love to hear what the experts have to say about them as well. Thanks so much.
At 95kg, the "life time" reputation of titanium is what sent me in that direction. After all, I like to ride fast/faster, but I do not race. The training just makes the bicycling more enjoyable for me. Carbon can look really cool to me, but it's well down the list of priorities for someone my size.
Second this request. Please cover all the major materials: steel, aluminium, and titanium. I'm hoping to buy a new gravel bike next year, hopefully to last me the remainder of my life (I'll turn 60 next year), DV.
Any material will fail in a crash. Any material will eventually fail with improper care. The issue is, how likely are you to crash and how difficult is it to achieve proper care. The first is somewhat out of our control and so you have to judge your use and surroundings. The second is simple enough for any bike material so there's no reason a user can't do it. That leaves us with use. Only 2 of the major bike TUBING materials will fail with use (which is really what this video is about mostly). Carbon fiber and Alu. And by "use", its stress cycles that are possible with the use of a bike for bike riding. That shouldn't need to be said but this is YT. Obviously a steel hammer can fail from use, but a steel hammer isn't a bike. That said, steel and Ti bikes can fail from use, because a frame isn't just the tubing. They are susceptible (as any frame) at the joints. So get high quality tubing (to achieve lightness and comfort), and pay for a good welder. Because then your bike will outlive you and your children.
@@cjohnson3836 I've seen steel frames come apart at the joints, principally chain stays and seat tube at the bottom bracket, occasionally the top tube-head tube junction after a hard crash. This was always from overheated machine welds making the tubing brittle and eventually unable to handle the torsional loads. Carbon frames seem to break along the middle of the tubes, hardly ever at the joints. So much for material integrity. Skillfully hand brazed steel is strong as hell. Have you ever tried to bend a CRMO tube by hand butted to paper thin 0.5 mm in the middle? Amazing how stiff it is without compromising its unique "modulus of elasticity." I've ridden two Columbus SL/SLX,SP bikes that ride the same as the day I bought them, 35 years and almost 200,000 miles ago, and too many wipeouts to count. Bent the derailleur hanger 45 degrees on one many years ago. Bent it back into alignment, chased the threads, and am still riding the bike. A head on collision on the other bike left me in the hospital for a week. The frame builder bent the fork and head tube back into alignment and the paint shows no evidence of cracking at the head tube lugs or fork crown. Amazing.
The best interviews and subject matter to date on GCN imho.More of these please! I have carbon,steel & Ti bikes from the 90's. Can you do this with titanium? Also further research with polymers and finishes would be great,Thanks !
Epoxy resins degrade quickly compared to acrylics, so the paint on a frame performs a vital function: it prevents moisture and and UV degradation (at least until the paint breaks down). How about producing a video on the paint systems used on bikes, carbon, aluminum and steel?
Thank you for creating such high quality content. It's great to hear the opinions of reputable experts on the technical aspects of frame construction and fatigue. For cars there are many independent organizations that test safety, reliability and performance. Cycling just isn't there yet, but it's great to see media like this moving us in that direction.
Sort of the same. I went with titanium, mostly because my sweat will destroy most any paint or powder coat job. It also does a number on aluminum and steel, though I have kept, and still ride, my 35 year old steel road bike.
Exceptional good content. Big thumbs up to Ollie for making this. I‘d be interested in the opinion of an expert from the aerospace/space industry on degredation of an unused, stored frame because in this area, spare parts tend to be stored for a long time. Also I‘d love to hear what professor Marrow has to say about metals. Is it really true that titanium is exceptional good at durability and if yes, why?
Storage conditions are a major contributor. In the sailplane world, we deal with airframe deterioration all the time. Gelcoat, used on the external surfaces fails in the hot/harsh UV conditions particularly found in the southern hemisphere. When the gelcoat fails, if not caught early enough, then the moisture that can get into the micro cracks get into the underlying structure. From there capiliary action and heat/cold cycles will accelerate the damage. Raw composite material exposed to UV will fail quite fast - often under a year, hence why the use of Gelcoat or PU to provide a protective layer. Another consideration is heat. Anything above about 55C and the resins will lose strength. So in this video where they talk about the fibres failing, you can also have the resin lose structure too if spent too long in a hot environment. "Hot" can be from just the paint colour - hence why most aircraft are almost all white. The difference in surface temps from white to something like red can be 5-10C, which is enough to push it over the limit and start causing failure. I know of one glider that, after a summer stored in a trailer in the aussie summer, lost enough strength that it became unusable - measured by the wing frequency dropping over 30%. Moral of the story - if you want composite stored structures to last for a long time - temp and climate controlled environments are essential.
@@justincouch6964 Thanks for the deep insights. I guess for space applications they will store their parts under a controlled inert gas atmosphere. At least they do so with their semiconductors.
I also am curious about the reputation of titanium. I tend to look at it as an improvement on steel, with regard to rust susceptibility and weight, but with the durability and strength steel provides. It would be nice to have a layman's presentation of the numbers to back that supposition up.
Titanium doesn't react chemically with anything you'll find on the road, so no rust, corrosion, etc. It flexes about twice as far as steel before yielding (permanent bend), and it's 40% lighter. Steel is stronger, stiffer, and heavier. Titanium and steel can flex forever without fatiguing, unlike aluminum. The performance of these 3 cycling metals is very similar, with trade-offs in weight, stiffness, durability, etc.
We've got you as a friend, Ollie, and thanks so much for these conversations with your professorial peoples, truly fascinating to hear their answers and reflections about the aging process of carbon frames in the real world. And maybe next time, you could ask how much longer a carbon frame will last if you're dropped all the time by your mates. Surely that adds another five years or so, you know, low stress and all.
Also adding the comments below, if there is a part 2, bring in someone from the sailing community as the u/v degradation on sailboats must be more extreme than for bicycles. Perhaps someone from Ben Ainslie's crew. Love the content Ollie!
I have a LOOK KG 251 which I bought new in 1999.It has carbon forks and carbon frame,however the main joining areas are aluminium. At present I have cycled 307.000km and the only noticeable fatigue is from the aluminium lugs.I have 2 other LOOK bikes that are full carbon,so it will be interesting to see how these cope in the future.I very much liked your video and also the video when you went to the LOOK factory .Thanks!
This kind of deep dive into science and engineering is brilliant. Do please give us more and as a user of metal frames, I too would love to her the analysis of the metals available for frame and component construction.
The German bike magazine "Tour" made a comparison between aluminium, steel and carbon frames regarding fatigue back in 2010. They put the frames under load over and over again to simulate thousands of kilometers. The first one showing signs of fatigue was the aluminium frame just over 70 000 km. Steel was the second after 115 000km. They stoped the test after 125 000 km because the frame wasn't showing any signs of material fatigue.
Frames have become lighter in the last 12 years, manufacturing processes have changed as well, there have been advancements in carbon fibre layup technology, these kinds of tests have to be performed constantly.
But... A carbon frame is not "just a carbon frame". Fibers, layup, epoxy, vacuum, baking, QC all varies. On well know brands, more than customers would like to know and a lot more than marketing wants you to know.
Great video. Thank you! I have a 16 year old Giant Carbon NRS-C1 that I bought brand new. Last year I completely rebuilt it with a 1-by GX Eagle drivetrain (something that didn't exist back when I bought it, but it lined right up!) and I still love riding it to this day. I've had some pretty bad crashes but so far, no issues with the frame. I think the lifetime of a hard-use carbon fiber mountain bike frame is mostly down to luck, assuming it was well-made to begin with.
As we are talking about CF frames seeing potentially a decade or more of use outdoors, regular application of a good polymer-based automobile / marine wax product is probably the best bet for keeping that CF frame in good shape (assuming you don't have the output of Chris Hoy). Since these products seal the surface and protect against UV, moisture, and oxidation damage, I would think this would help, especially for bikes painted in darker shades, like red, blue, and black. These colors should benefit the most from a regular wax treatment, as these pigments are most vulnerable to UV damage. The sealed surface should also help protect the epoxy from oxidation and moisture damage too. Think of paint protection and clear coats treatments on automobiles and how they are used to prevent UV and moisture absorption and oxidation damage as an analogy.
I have owned and ridden my 35 year old kestral 4000 many many miles. Still no issues or cracks with the frame. Actually i met a few weeks ago the engineer who worked on the structure back in 1986. He was happy to see it was still in good shape.
What a fascinating and insightful set of discussions. I bought my steel frames in hopes i can pass them down to my children and children’s children and my carbon frame only for special occasions. I guess nothing is forever - even forever bikes. 🤷♂️
Thank you for the time-stamps. So many creators don't make the effort, and it hinders my viewing experience at times. This is my first watch of your content due to youtube recommend, and you get Subscribe from me from first impressions.
It's a perfect union. While the cyclist ages and loses strength and flexibility the bike ages and loses its stiffness, becoming a more compliant partner as the years wear on.
You're on a roll, Ollie. You're broaching so many important questions that CF bike owners have about their bikes. My situation: I own a 2016 Bianchi Specialissima with the matte finish, which was stored in our home, but now that our college graduate/graduate school student has moved back in, my bike has been relegated to our garage which in Southern California can become quite warm. My question would be does long-term exposure not to ultraviolent light, but simply warm temperatures in a garage degrade a CF bike's epoxy resin or laminate?
There is a way to actually monitor the evolution of fatigue in a frame by "attaching" tell-tale structures or foils to the frame at critical locations, where the highest loads are expected, which have a much lower fatigue resistance than the frame itself. For example a printed resistive layer on the frame will change its resistivity as the material ages under repeated loads because of the gradual growth and number of micro cracks in the resistive layer. These resistive layers can be tailored towards the expected accumulated stresses over time to give an indication of remaining 'life time' in the frame. These foils or tell tale structures can be protected under the lacquer with only the contact points exposed. Such elements are used in the aerospace industry to monitor the stability of aircraft wings, although this is primarily done during the development work in aircraft and once the required knowledge has been gained during development/testing these tell tale elements are no longer needed as the structure is by then well known and understood and load factors can be accumulated by other means. However on a push bike, especially in race situations the loadings are less predictable and there are no other means of measuring loads applied to the frame (except for maybe power input by the rider).
Hah, I can imagine pitching this to the sales team: 'Oh, and BTW, production units should have a bunch of telltale stickers in places where our tests have shown early frame failure, so that the costumer is always aware of how their brand-new, super-expensive carbon frame is slowly dying with each pedal stroke'.
@@AG-el6vt On the other hand, it could be a measure to tell customers that their bike is still perfectly OK since it has been designed for professional athletes who put regularly many hundreds of watts through the pedals for hours on end, day after day, whereas 'you, dear customer' will be able to do maybe 200 or 300 watts for an hours or so once a week and hence under your puny exertions the frame will live for ever. ...
Mileage indicator of some sort, built in to the frame? Seems like the lowest common denominator of lifetime health of the material, could be anywhere since not measuring specific strain etc.
I highly recommend everyone carefully inspect your bike every 3 months including the fork after a good wash. I have found the following in 17 years of riding carbon bikes: 1. Cracking around the fork crown at junction of carbon fork blades and aluminum fork steerer (bike had been in several crit/bunch crashes) - 2005 Giant OCR1 2. cracks on the underside of chain stay of two bikes frames (one cheap Chinese dengfu FM01 cracked due to being crap, BH G6 which was crashed at 53kmh) 3. Cannondale CAAD10 fork steerer cracked due to stem being so thin (3mm wide at its narrowest point due to stupid attempt at weight savings on stem internals) - poor design! Replaced with carbon stem which has no cut out on the inside of stem (fully supported) and used a 50mm long expander plug. Cannondale one was 15mm!
Agree with checking often.... I use Carbon Forks with Alloy Crowns. (Exotic Brand) Only the tubes are carbon. I have over 8000 miles on one fork (most very rugged CX trail riding) and recently inspected it, no signs of any damage. I do not think I would every trust a fully carbon fork on the trails.
@@MrJx4000 I found large cracks that were obvious to the eye (a few mm long) but I have watched videos of people using ultrasonic equipment to scan carbon fibre
A most excellent tech inquiry. I am nowhere even near being an engineer, but I still knew the answers to some of the questions posed even before they were answered, the 'paper clip' analogy to the stresses which cause failure in a metal frame being the most direct (I was thinking it even before the professor used it to demonstrate his point). I also figured out a while ago that the resins/epoxies used in carbon fiber composite frames are what would 'age out' over time, and become brittle, and even more so/quicker yet if exposed to long term UV rays. PLEASE be sure to ask Professor Morrow (I am guessing with many multiple doctorates) in any future discussions about the crystalline grain structures of the various alloys used in metal frame tubing (especially titanium alloys!), and how they differ in stress cycle to failure longevity, and even how they differ in hard, sharp, spike amplitude IMPACT failure scenarios. It would bother me if i just dropped $20K USD on a fully kitted out Dogma (or whatever their up to the second top of the line is right now?) rig knowing that if I used it as it was built to be used, I would have to replace it in less than 5 years time. But then again, if I had Jeff Bezos type coin, and was incessantly worried about my kit being 'dated' even a slight bit style wise, I'd be dropping that much every other year or so anyway.
Really great video Olly, really good questions and answers from the experts. It's good to compare the different frame materials, and good to hear about fatigue stress levels and deflection cycles. It would be really good to do a video on tube shapes and sizes and wall thicknesses, which drives the stress and deflections, and then the forming and shape of the joints, such as the bottom bracket area, and how that can stiffen or flex the feel, and is pretty much independent of material. Great to see some engineering principles talked about!
This is the real content!. I bought a Giant Cadex CFR 4 originally it was a racing road bike ,one of the first carbon bikes ever made, but its been transformed into a fixed gear bicycle the frame and the fork are from the 90s the other components have been changed and it's still rides like a dream.. tho I always have that thought on the back of my head when im ridin, especially fast over a rough terrain, that it could actually snap in half....only the lugs are aluminium, the tubes carbon.....I hope it will last me another 30 years, fingers crossed....
Ja, I am in the same situation. My hope is that failure is not catastrophic, and simply results in a "funny" feeling ride that can be seen as small cracks. Then, assuming my vision is still good, I can detact a failed frame.
I am loving these videos from Ollie. What's next? If I can make a recommendation... different power meter technology. Would love to see a discussion of what goes in to pedal based vs crank arm vs spindle, etc.
Look up the channel "Peak Torque", he's made several very in depth videos about the engineering behind power meters! Great channel, I believe he is an engineer in the bike industry iirc
The "dead" feeling is by no means limited to pro sprinter's bikes. Here in Girona many pros (including domestiques and climbers) talk about the difference in feel between their training bike (which may do around 30,000 km in a season) and the bikes teams reserve for them to ride in races; the difference between them is more noticeable as the season progresses. When new bikes are issued at the start of the next season even the dedicated race bikes feel better to ride.
So that would suggest that 30,000 km is enough to cause significant fatigue.. That's not very much! It would mean that even your average keen amateur doing just a few thousand km a year is going to "wear out" a frame in 5 years in terms of ride feel. OK, they will be putting out less power and so the loads wil be less, but not by an order of magnitide.
@@neil7769 That's just a couple of years for some. Never saw a manufacturer mentioning this, every year the frames are 5% lighter, 3% more rigid and 6% more compliant but the fact they wear out is omitted for some reason...
So riders complain about the frames, which is one of the things they depend on to be supplied by their teams/sponsors... Hardly a reliable source, needs some scientific backing.
Aluminum frames will fail eventually even when not crashed. Steel and titanium frames built properly and not crashed will last a life time and more if not rusted.
I love that video and its important to take closer looks on materials and trends. Thanks for that disenchantment of those machines. Its important to know and again and again its hard to argue with other cyclists about the properties of their loved machines. Its obviously an emotional topic but when I talk to them from my point of view as a Technical Product Designer it sometimes ends as a little bit like I have insulted somebody, because I mention the lowe suitability for everyday use and that a carbon frame has to be used more careful. The people love their light and beautyful bike and I love my carbonbike as well but if I have to make a choice to have and to keep one bike for ages I would not prefer it. The use in professional sport is a total different topic because noone cares that they use one or more than one new bike every year.
Just got a CF MTB used for a good price and felt a bit unsure about the CF part. This vid really gave me confidence, especially the gracefully failing aspect. It's really reassuring to know that your frame first will get noticeably softer and maybe start delaminating somewhere instead of just instantly cracking like a metal frame would probably do!
“It’s nice to get some interesting questions…” - Tom must field some real daft questions frequently. Top marks Ollie - great interviews and great vid 👏
Best GCN video yet and really interesting to learn from real experts in the field. I would like to add a couple of points, one is that while NDT (non destructive testing) is talked about for testing Carbon frames after a crash, this is rarely available. metals are sonorous so they can be checked by "ringing" them. Secondly Canyon (as an example) recommend changing carbon forks at six years, obviously this is a sensible compromise as they don;t know the usage but it is an expense that requires budgeting and could come to light in the event of a post crash court case.
My 19yr Madone has become more comfortable over time. I do inspections when I clean it. Still going strong. I'm not a racer, just a Marine staying fit.
I do not know a single cyclist that likes carbon at all . Even less anyone liking a bike over a 1000 quid . I see retro old Raleigh's making a comeback for the last forever fix for sixpence ..a real bicycle . Very informative post . Thankyou .
My frame's a 20 year old carbon one and it's still fine. It's kept kept dry, clean and in an outhouse away from light. It's had to be repaired once and I can tell the difference between the before and after, but it's not enough to stop me riding it.
beat you, I have a Dunlop Hotta Perimiter TT bike with Specialized tri spokes wheels on it. The bike and wheels are circa 1993 and the wheels have a 1993 sticker on them. I changed the forks for bladed MDT units because of aerodynamics as it is a TT bike but the frame and wheels have absolutely no signs of deteriation or cracking or anything else on them after 29 years. I still regularly train on the bike but now ride a Trek Speed Concept in competition with HED 6/9 wheels.
The basics of composite materials are simple to understand. Stress, strain, Youngs modulus, layup direction fibre/resin composite etc. Modelling them in finite element software in mid 90's for my thesis was a bit more challenging!
'With knowledge comes responsibility'....let's hope bike manufacturers get better acquainted with this sort of knowledge and apply it in their production.
I love this format. Overall I'm very much into deep dives that deserve their name and are carefully planed and researched. Knowledge ist nice and I would guess, that many of the viewers do appreciate that kind of content.
That was the most interesting topic in a long time. Ollie, any way the average user of carbon frames can identify mentioned weaknesses before they become a safety concern? It would be interesting to talk to the industry itself about this topic and hear their recommendations.
You can get your frame x-rayed in what ever way they x-ray carbon frames..........Like Canyon does this to their frames after they get them from Asia..........the frames are x-rayed in Asia also but Canyon spent the 500,000 for their own x-ray machine............they dont want failures.........I bought a Canyon Endurace 2 months ago.
no, carbon will usually fail completely before it will show any signs of damage. it will be practically impossible for you to tell visually on a painted carbon surface.
@@adrianc6534 It really doesnt work that way,generally cracks appear first,then things go downhill from there............buying no name chinese carbon parts is asking for disaster.
Great content, real technical information is essential. The thing that shocks me the most is that anybody hadn’t already figured this out! Carbon bikes are throwaway consumer goods. Most quality steel frames that are already 40 or 50 years old will, if not stored outdoors, still be giving their owners a joyful riding experience after every carbon frame ever made is in a landfill.
It's not that it isn't as strong it's that it REALLY comes down to the welding and when many ti frames are very small and very boutique the QC can be an issue but the tubing is yes basically indestructible
I have a 29 year old Dunlop Hotta Perimeter TT bike with a carbon finish with 1993 carbon specialized carbon finish tri spokes tt wheels, all in perfect condition with no cracks whatsoever. There is your answer ollie, going training on it this afternoon.
@@JasonDBike I also have a modern trek speed concept i do competition on now. I bought it expecting it to be much faster because it has modern wider wheels and a slightly more aerodynamic profile and obviously lighter. The difference in speed is immeasurable and could easily be the difference between one day and a slightly better weather day,either way. I am in the same position on both bikes and that is what is important. We are being conned, I am sure !
Exceptionally high quality content. Thoroughly enjoyed it, and also the questions asked were brilliant. I'd like to know how aluminum bike frame will compare with different levels of carbon T300, T700, T1100, etc) frame, a side by side comparison on longevity and maybe for carbons, the"un-deadness" of the frame, since they won't just break so easily. Cheers
It would be interesting to hear what a polymer scientist has to say about the resins used in carbon fiber bike frame fabrication. Especially since the effect of UV came up a few times. Is there a resin that limits UV's impact?
The resin itself can have UV inhibitors added, but paints (including clear coats) are better. As was pointed out, they also have a limited life. Down under where the UV is strong it's a real issue.
It would interesting if the Professor of nuclear materials science could explain how an RBMK carbon fibre frame can explode. I told Prof. Dyatlov that my carbon frame exploded and that there was graphite amongst the bicycle rubble on the road....he started shouting saying *_"YOU DIDN'T SEE ANY GRAPHITE because it wasn't there!"_* The dosimeter readings of the bike wreckage maxed at out 3.6 roentgen per hour, not great but not terrible either.
There is a resin that limits UV impact, but the question then is does it work with carbon fiber to make a good bike? Acrylic resins have excellent UV resistance. They aren't as tough as epoxies (keep in mind there are a lot of different kind of epoxy resins - acrylics, too).
Have used my carbon Roubaix for 14 years now. Feels like new when riding. However, am getting a new bike just now. Old frame will now be permanently strapped to my trainer. Expect 15-20 more years of use. :-)
Just curious did the bike ever fall like from standing and also ever hit roughy roads ie pot holes and no problem or any impact and still had no issue ?
@@JitinMisra who does not fall over for 14 years with cleats 😂 - and pot holes are everywhere but tires and wheels take most of the beating. Got run down by a taxi once and repairs included a new fork and 5 ribs. Frame itself amazingly still OK.
@@meibing4912 I just bought a trek fx bike that is all carbon, to upgrade from my previous bike which was aluminum with carbon fork. Gotta say the difference is amazing, on how smooth it is over bumps. But I sometimes feel paranoid on if I have to baby it. I only ride paved roads though not jumping mountain bikes
@@JitinMisra I had the same feeling/fear in the beginning. 😁Just avoid deep scratches. I recently slammed a (new) Specialized bike with 50mm carbon wheels into a massive pothole going downhill. So surprised the wheel did not even go out of tune. Good luck and enjoy!
16:23 Tom Bahto - Senior Specialist, Materials Engineer: "There must be millions of carbon fiber bike frames out there that are 15 to 20 years old, and they are not falling apart. So by and large, I think the cycling public are pretty safe on aging carbon fiber bikes."
Because the load experience by those frame is below the limit of frame fatigue design. And most cyclist dont produce power above 400 watt that's even less than 1 horse power
@@arifazhari7598 Thats about half a horsepower. But real horses put out multiples of 1 horse power.......HP is a measure of long term power output, not short bursts.
Would be cool to see a comparison or test of heavily used pro carbon bikes and carbon bikes that are new or used by amateurs. Kept thinking about the sailing industry throughout the vid. In sailing you are starting to see more older carbon components that have been frequently exposed to UV, saltwater and high loads but my understanding is that failures aren't as common as one would expect.
Nice Ollie fascinating, the information goes along well with my personal experience of Carbon Fibre failure that I experienced over the 25 to 30 year of using it in cycling, in frames & components. I the aluminium idea but would if you could cover these areas with Titanium frames also?
As a composite glider technician... I can say, yes material softens as described... But engeniered correctly it lasts longer than any metal... I see gliders from the late 60th regularly... In snowboards you can definitely feel that deadening... Unless you buy burton, who prestress their boards and engineer that softening before hand
Really great content thank you more if this please. Great balanced view and also brilliant to see well reasoned and knowledgeable people posting in the comments, seems the sailing world has it hardest due to the external weather and storage factors. My 2 pennies worth on bikes/frames feeling dead. For those of us who trained and raced on the same bike and put race wheels on stiffness or spoke tension etc and tyres make a bike feel drastically different obv different for high power sprinter pros but a real factor
Yes, I would imagine square acres of carbon fiber composite material exposed long term to sun, wave 'crash' stresses, and salt water does not help it's longevity one bit.
@@richardggeorge 14 kg are not that much for a commuter bike. My hardtail aluminum MTB also weighs 14 kg. As long as it's not hilly tires have the biggest effect, a tire with low rolling resistance (10 to 14 W) is a difference like night and day compared to a touring bike tire with 25 W
I experienced UV destruction on my friend’s Orbea Orca 2009 frame about 3 years ago. Clear coat matte finish that showcased the carbon fiber.. 10 years of hot summer riding did it in. The chain stays got real punky like a sheet of plywood that had severe water damage. His bike was leaning against his garage it rolled forward and a corner of a brick pillar and a created a hole. We then poked around with fingers and started to create other holes. I had a similar type of frame at the time that I wound spray UV protective polish on as much as I could. My latest is a painted frame.
I think road cyclists stress way too much over these topics, when even the roughest asphalt or even gravel wouldn't compare to the stress applied to a bike frame that of a MTB descend. Full carbon frames are also made and used on mountain bikes yet they aren't noticeably prone to fatigue wear that people complain about it to an abnormal extent. Sure, one might say those frames are more reinforced than road bike ones, but fatigue is an integral problem the entirity of the material suffers as it get exposed to deflection and small impacts, according to these experts. On the bottom line, will YOU keep a bike for long enough that it's something to worry about? While one day the current carbon bikes will become what the collectible, vintage steel bikes of the 70s onwards are today, even if you keep your modern-day bike for decades, or you or someone buys it much down the line, you won't view it as an everyday, dependable piece of sports equipment.
Tom Batho! That’s a face and a name I haven’t seen in a few years, since the heady days of 3T Racing and the BUKC! Glad you’re doing well mate, and proper interesting info - thanks!
Probably the best, most informative video GCN has ever produced. Top presenter too, well done Ollie 👌
Ollie's Ph.D in a hard-science field really adds value to GCN -- it brings an added perspective that I love!
Is it divine proclamation that Ollie is wearing a halo during the summary section 34:33, or a bit of cameraman’s fun?
Totally agree.
Probably....
Make a GCN+ doc on frame building, testing and design!!
I own a Trek 5200 from 1998. I raced that frame from 1998 - 2009 I officially retired it only because I I wanted to try out a Madone. I still own that 5200 today and it's just as stiff as it was brand new. I don't race it anymore but I do use it on tours rides, fundraisers, and riding to work. It doesn't just sit. I do keep it inside my house when not using it. It is well cared for as in maitained. The frame doesn't feel dead it's 26 years old I estimate over 200,000 miles on it and it's just as if not faster then most modern bikes
"It depends" is one of the most common answers given by engineers to engineering questions. For good reason ;)
cos there's a lot of variables
Yeah and thats quite obvious why. You have so many different situations and factors playing a roll for everything in our world. Thats why i dont trust people who say its like this abd nothing else.
Depends are adult diapers...
@@hondasaurusrex6998 Until someone gets hurt, or dies, as a result of a decision made without taking all the relevant factors into account.
I guess that you are not an engineer then? ;)
Depends on what you're asking?
The fatigue on Mark Cavendish's frames is directly related to how many mechanics he's thrown it at.
Real talk 🥴🤔
This is hilarious 🤣
Ahh the king of hissy fits
Now that is funny. 😂
Correct! He’s a man baby!
This is such great content. In a world where the majority of YT videos is an ad for something it's just great to see plain informative content. Thanks!
Most of the GCN Videos are just elaborate Ads
It was refreshing that this GCN content wasn't an ad.
My take out is that Composite Carbon Fibre has as many positives as negatives and that while it is massively strong, the way it is applied to bicycles makes it extremely delicate and in fact less robust than metal frames from a reliability and longevity point of view. My worry is that while it is strong while new, degradation from continuous vibrational amplification is known to weaken the very best polymer substrates that form and bind the Carbon fiber matrix. Basically even the smoothest road surface creates vibration and combined with the intermittent shock forces of striking the occasional pothole obviously will accelerate micro degradation untill catastrophic failure. This may be an unpopular opinion but is based on the sad fact that everything has a lifespan and nothing lasts forever 😕
Finally a proper engineer on RUclips and not a self proclaimed expert trying to gain RUclips followers and set a anti bike industry narrative to gain sales and support for the brands they represent, whilst telling everyone you should not do excactly what they are doing. Or implying excessive force damage(a crash) is somehow defective manufactoring. This is very insightful
Ollie - I love these videos of interviewing cutting edge scientists. I would ask not only about aluminum and steel, but titanium as well when you are able to perform the second interview. I certainly would like to see more videos like this one!
You look like yu gi oh
Aluminum frames will crack over time as metal is crystal. How long depends on design and heat during construction. I had a road bike fail after 8 years of almost daily use. I also have a mtb frame that's over 10 years old that has not cracked yet and it is used a few days a week on trails without Jumps. I would not worry about steel frames unless it's rusted our crashed hard.
This is the content I want from GCN Tech, love it.
Been running the same Chinese frame for over 9 years on a hard tail XC race bike. I however have recently moved to more trails riding and have taken that bike through more than it should have ever been through. Still holding up :)
Hey do tell me about the frame, brand and the type of riding you did! I just restored a now 12 year old (maybe 13) scott scale xc frame with reinforcement fibers from an f1 vendor... I've also had the frame x-rayed by a friend who's willing to do it for a fare price at different levels, came back safe...anyways I'm converting it to gravel but still want do hit a few mountains on it haha we'll see🤷 also I've riding prior to it's new fabrication updates with no issues....but the whole idea of the reinforcement was because it was old; so like mentioned in the video "needed a touch-up".
Are you still alive?
I own a carbon sprint kayak and a carbon wing paddle that i still paddle regularly.The sprint kayak is 22 years old and the paddle 25.
Don't be a fool, don't believe what industry says.
Thnx Ollie, great content. (I was getting fed up with all the sponsored bits, it feels good to not have to be cynical about a topic because of the segment being sponsored)
100% want to see a before and after season bike stiffness test for a sprinter.
Wow, now this is an awesome content from GCN! Understand GCN can't be producing these type of contents all the time but keep it coming! Good one GCN, good one Ollie and thanks to the experts too for their insight! Hoping for a part 2 n maybe 3 from those polymer experts and then about the other materials like aluminium, steel and especially titanium!
Hands down the best GCN presentation I have watched, 100% informative and interesting. Plus, how can you not like Ollie?
Here’s my takeaway:
Thinking about carbon failure is energy draining which robs us of watts. Which then prevents Ollie exceeding 1000 watts. Now off to that video.
I really love listening to gcn tech when I'm working on my bike. I have learned a lot of stuff just by listening to you guys
One of my favorite Tech videos to date. Please do one for metal frame materials. I have a particular interest in titanium and stainless steel and would love to hear what the experts have to say about them as well. Thanks so much.
At 95kg, the "life time" reputation of titanium is what sent me in that direction. After all, I like to ride fast/faster, but I do not race. The training just makes the bicycling more enjoyable for me. Carbon can look really cool to me, but it's well down the list of priorities for someone my size.
Second this request. Please cover all the major materials: steel, aluminium, and titanium. I'm hoping to buy a new gravel bike next year, hopefully to last me the remainder of my life (I'll turn 60 next year), DV.
Also second the request on titanium (a Jan Guillem titanium bike owner)
Any material will fail in a crash. Any material will eventually fail with improper care. The issue is, how likely are you to crash and how difficult is it to achieve proper care. The first is somewhat out of our control and so you have to judge your use and surroundings. The second is simple enough for any bike material so there's no reason a user can't do it. That leaves us with use. Only 2 of the major bike TUBING materials will fail with use (which is really what this video is about mostly). Carbon fiber and Alu. And by "use", its stress cycles that are possible with the use of a bike for bike riding. That shouldn't need to be said but this is YT. Obviously a steel hammer can fail from use, but a steel hammer isn't a bike. That said, steel and Ti bikes can fail from use, because a frame isn't just the tubing. They are susceptible (as any frame) at the joints. So get high quality tubing (to achieve lightness and comfort), and pay for a good welder. Because then your bike will outlive you and your children.
@@cjohnson3836 I've seen steel frames come apart at the joints, principally chain stays and seat tube at the bottom bracket, occasionally the top tube-head tube junction after a hard crash. This was always from overheated machine welds making the tubing brittle and eventually unable to handle the torsional loads. Carbon frames seem to break along the middle of the tubes, hardly ever at the joints. So much for material integrity.
Skillfully hand brazed steel is strong as hell. Have you ever tried to bend a CRMO tube by hand butted to paper thin 0.5 mm in the middle? Amazing how stiff it is without compromising its unique "modulus of elasticity." I've ridden two Columbus SL/SLX,SP bikes that ride the same as the day I bought them, 35 years and almost 200,000 miles ago, and too many wipeouts to count. Bent the derailleur hanger 45 degrees on one many years ago. Bent it back into alignment, chased the threads, and am still riding the bike. A head on collision on the other bike left me in the hospital for a week. The frame builder bent the fork and head tube back into alignment and the paint shows no evidence of cracking at the head tube lugs or fork crown. Amazing.
The best interviews and subject matter to date on GCN imho.More of these please! I have carbon,steel & Ti bikes from the 90's. Can you do this with titanium? Also further research with polymers and finishes would be great,Thanks !
1993 Koga Miyata SkyCarbolite here ;)
X2
Glad you are here, I got a carbon frame in 2016-2018 about and was worried it last 5 years only
Epoxy resins degrade quickly compared to acrylics, so the paint on a frame performs a vital function: it prevents moisture and and UV degradation (at least until the paint breaks down). How about producing a video on the paint systems used on bikes, carbon, aluminum and steel?
Need to do a 'part two' with a polymer scientist! Very interesting. Thanks, Ollie
Agreed!
Yes +2 please 🙏
I think you are looking for a “material engineer”
glad to see a person from a historic f1 manufacturer in your channel .
Thank you for creating such high quality content. It's great to hear the opinions of reputable experts on the technical aspects of frame construction and fatigue. For cars there are many independent organizations that test safety, reliability and performance. Cycling just isn't there yet, but it's great to see media like this moving us in that direction.
One of the most honest and informative interviews in a very long time. Supported my decision of a long time ago to stay with aluminum and steel.
Sort of the same. I went with titanium, mostly because my sweat will destroy most any paint or powder coat job. It also does a number on aluminum and steel, though I have kept, and still ride, my 35 year old steel road bike.
Exceptional good content. Big thumbs up to Ollie for making this. I‘d be interested in the opinion of an expert from the aerospace/space industry on degredation of an unused, stored frame because in this area, spare parts tend to be stored for a long time. Also I‘d love to hear what professor Marrow has to say about metals. Is it really true that titanium is exceptional good at durability and if yes, why?
Storage conditions are a major contributor. In the sailplane world, we deal with airframe deterioration all the time. Gelcoat, used on the external surfaces fails in the hot/harsh UV conditions particularly found in the southern hemisphere. When the gelcoat fails, if not caught early enough, then the moisture that can get into the micro cracks get into the underlying structure. From there capiliary action and heat/cold cycles will accelerate the damage. Raw composite material exposed to UV will fail quite fast - often under a year, hence why the use of Gelcoat or PU to provide a protective layer. Another consideration is heat. Anything above about 55C and the resins will lose strength. So in this video where they talk about the fibres failing, you can also have the resin lose structure too if spent too long in a hot environment. "Hot" can be from just the paint colour - hence why most aircraft are almost all white. The difference in surface temps from white to something like red can be 5-10C, which is enough to push it over the limit and start causing failure. I know of one glider that, after a summer stored in a trailer in the aussie summer, lost enough strength that it became unusable - measured by the wing frequency dropping over 30%.
Moral of the story - if you want composite stored structures to last for a long time - temp and climate controlled environments are essential.
@@justincouch6964 Thanks for the deep insights. I guess for space applications they will store their parts under a controlled inert gas atmosphere. At least they do so with their semiconductors.
I also am curious about the reputation of titanium. I tend to look at it as an improvement on steel, with regard to rust susceptibility and weight, but with the durability and strength steel provides. It would be nice to have a layman's presentation of the numbers to back that supposition up.
Titanium doesn't react chemically with anything you'll find on the road, so no rust, corrosion, etc. It flexes about twice as far as steel before yielding (permanent bend), and it's 40% lighter. Steel is stronger, stiffer, and heavier. Titanium and steel can flex forever without fatiguing, unlike aluminum. The performance of these 3 cycling metals is very similar, with trade-offs in weight, stiffness, durability, etc.
@@justincouch6964 Wow, this puts new light on the infamous A350 paint row
We've got you as a friend, Ollie, and thanks so much for these conversations with your professorial peoples, truly fascinating to hear their answers and reflections about the aging process of carbon frames in the real world. And maybe next time, you could ask how much longer a carbon frame will last if you're dropped all the time by your mates. Surely that adds another five years or so, you know, low stress and all.
Also adding the comments below, if there is a part 2, bring in someone from the sailing community as the u/v degradation on sailboats must be more extreme than for bicycles. Perhaps someone from Ben Ainslie's crew. Love the content Ollie!
ps you dont instantly die if your mast cracks
@@ohhi5237 This would of course depend on the boat and how rapid the rate of deceleration is.
@@arcboy2011 a proper boat, like one that floats and u can do baoty things in, they costs as much as a full house, yes thats more than your bike bye
Please do a segment with Professor Marrow about Titanium, Steel and Alloy as well..
I have a LOOK KG 251 which I bought new in 1999.It has carbon forks and carbon frame,however the main joining areas are aluminium. At present I have cycled 307.000km and the only noticeable fatigue is from the aluminium lugs.I have 2 other LOOK bikes that are full carbon,so it will be interesting to see how these cope in the future.I very much liked your video and also the video when you went to the LOOK factory .Thanks!
wow
I appreciate this kind of content especially given how the vast majority of channels have a focus on promoting rather than critical review
This kind of deep dive into science and engineering is brilliant. Do please give us more and as a user of metal frames, I too would love to her the analysis of the metals available for frame and component construction.
The German bike magazine "Tour" made a comparison between aluminium, steel and carbon frames regarding fatigue back in 2010. They put the frames under load over and over again to simulate thousands of kilometers. The first one showing signs of fatigue was the aluminium frame just over 70 000 km. Steel was the second after 115 000km. They stoped the test after 125 000 km because the frame wasn't showing any signs of material fatigue.
Sauce?
Frames have become lighter in the last 12 years, manufacturing processes have changed as well, there have been advancements in carbon fibre layup technology, these kinds of tests have to be performed constantly.
But...
A carbon frame is not "just a carbon frame".
Fibers, layup, epoxy, vacuum, baking, QC all varies.
On well know brands, more than customers would like to know and a lot more than marketing wants you to know.
This is the type of misleading comment we hear from pro carbon people all the time. How indestructible it is despite empirical evidence.
18.17 "Fatigue is a cycling process" Certainly is for me....😀
Great video. Thank you! I have a 16 year old Giant Carbon NRS-C1 that I bought brand new. Last year I completely rebuilt it with a 1-by GX Eagle drivetrain (something that didn't exist back when I bought it, but it lined right up!) and I still love riding it to this day. I've had some pretty bad crashes but so far, no issues with the frame. I think the lifetime of a hard-use carbon fiber mountain bike frame is mostly down to luck, assuming it was well-made to begin with.
I just bought a 2017 Cirrus Pro carbon and I always have the fear of my frame collapsing on me.
As we are talking about CF frames seeing potentially a decade or more of use outdoors, regular application of a good polymer-based automobile / marine wax product is probably the best bet for keeping that CF frame in good shape (assuming you don't have the output of Chris Hoy). Since these products seal the surface and protect against UV, moisture, and oxidation damage, I would think this would help, especially for bikes painted in darker shades, like red, blue, and black. These colors should benefit the most from a regular wax treatment, as these pigments are most vulnerable to UV damage. The sealed surface should also help protect the epoxy from oxidation and moisture damage too. Think of paint protection and clear coats treatments on automobiles and how they are used to prevent UV and moisture absorption and oxidation damage as an analogy.
I have owned and ridden my 35 year old kestral 4000 many many miles. Still no issues or cracks with the frame. Actually i met a few weeks ago the engineer who worked on the structure back in 1986. He was happy to see it was still in good shape.
Best GCN video I've ever watched.
ACTUAL truth instead of guesses opinions and pretend science.
More scientists and engineer interviews please!
: )
Extremely informative content from dr.ollie and GCN ,feeding my hunger about bike as a pandemic newbie cyclist.
More content deserve to be waited.
What a fascinating and insightful set of discussions. I bought my steel frames in hopes i can pass them down to my children and children’s children and my carbon frame only for special occasions. I guess nothing is forever - even forever bikes. 🤷♂️
Ultra high end steel like 953 might well be termed forever bikes. They say stainless steel cutlery will be the last thing left of humanity.
@@sandydennylives1392 toyotas , kirby vacuums....built forever
@@crabtrap I can attest to toyota. Not so much for Kirby making it to playstation 5, I might be wrong...
Thank you for the time-stamps. So many creators don't make the effort, and it hinders my viewing experience at times. This is my first watch of your content due to youtube recommend, and you get Subscribe from me from first impressions.
It's a perfect union. While the cyclist ages and loses strength and flexibility the bike ages and loses its stiffness, becoming a more compliant partner as the years wear on.
Until they both break! 😁
steel ages a lot better, carbon just DIES in sunlight
Getting dropped causes stress to the bike also
lol
You're on a roll, Ollie. You're broaching so many important questions that CF bike owners have about their bikes. My situation: I own a 2016 Bianchi Specialissima with the matte finish, which was stored in our home, but now that our college graduate/graduate school student has moved back in, my bike has been relegated to our garage which in Southern California can become quite warm. My question would be does long-term exposure not to ultraviolent light, but simply warm temperatures in a garage degrade a CF bike's epoxy resin or laminate?
There is a way to actually monitor the evolution of fatigue in a frame by "attaching" tell-tale structures or foils to the frame at critical locations, where the highest loads are expected, which have a much lower fatigue resistance than the frame itself. For example a printed resistive layer on the frame will change its resistivity as the material ages under repeated loads because of the gradual growth and number of micro cracks in the resistive layer. These resistive layers can be tailored towards the expected accumulated stresses over time to give an indication of remaining 'life time' in the frame. These foils or tell tale structures can be protected under the lacquer with only the contact points exposed. Such elements are used in the aerospace industry to monitor the stability of aircraft wings, although this is primarily done during the development work in aircraft and once the required knowledge has been gained during development/testing these tell tale elements are no longer needed as the structure is by then well known and understood and load factors can be accumulated by other means. However on a push bike, especially in race situations the loadings are less predictable and there are no other means of measuring loads applied to the frame (except for maybe power input by the rider).
Hah, I can imagine pitching this to the sales team: 'Oh, and BTW, production units should have a bunch of telltale stickers in places where our tests have shown early frame failure, so that the costumer is always aware of how their brand-new, super-expensive carbon frame is slowly dying with each pedal stroke'.
@@AG-el6vt On the other hand, it could be a measure to tell customers that their bike is still perfectly OK since it has been designed for professional athletes who put regularly many hundreds of watts through the pedals for hours on end, day after day, whereas 'you, dear customer' will be able to do maybe 200 or 300 watts for an hours or so once a week and hence under your puny exertions the frame will live for ever. ...
@@robertrjm8115 if you are at that level of rider, your bike is disassembled and sent for xray and inspection. no need for stickers
Mileage indicator of some sort, built in to the frame? Seems like the lowest common denominator of lifetime health of the material, could be anywhere since not measuring specific strain etc.
Love GCN, Ollie, tech, carbon fiber, and weekend naps. This video hit the ball out of the park! ⭐⭐⭐⭐⭐
I highly recommend everyone carefully inspect your bike every 3 months including the fork after a good wash. I have found the following in 17 years of riding carbon bikes:
1. Cracking around the fork crown at junction of carbon fork blades and aluminum fork steerer (bike had been in several crit/bunch crashes) - 2005 Giant OCR1
2. cracks on the underside of chain stay of two bikes frames (one cheap Chinese dengfu FM01 cracked due to being crap, BH G6 which was crashed at 53kmh)
3. Cannondale CAAD10 fork steerer cracked due to stem being so thin (3mm wide at its narrowest point due to stupid attempt at weight savings on stem internals) - poor design! Replaced with carbon stem which has no cut out on the inside of stem (fully supported) and used a 50mm long expander plug. Cannondale one was 15mm!
Agree with checking often.... I use Carbon Forks with Alloy Crowns. (Exotic Brand) Only the tubes are carbon. I have over 8000 miles on one fork (most very rugged CX trail riding) and recently inspected it, no signs of any damage. I do not think I would every trust a fully carbon fork on the trails.
How do you check for micro cracks in carbon fibre--dye penetrant?
@@MrJx4000 I found large cracks that were obvious to the eye (a few mm long) but I have watched videos of people using ultrasonic equipment to scan carbon fibre
A most excellent tech inquiry.
I am nowhere even near being an engineer, but I still knew the answers to some of the questions posed even before they were answered, the 'paper clip' analogy to the stresses which cause failure in a metal frame being the most direct (I was thinking it even before the professor used it to demonstrate his point).
I also figured out a while ago that the resins/epoxies used in carbon fiber composite frames are what would 'age out' over time, and become brittle, and even more so/quicker yet if exposed to long term UV rays.
PLEASE be sure to ask Professor Morrow (I am guessing with many multiple doctorates) in any future discussions about the crystalline grain structures of the various alloys used in metal frame tubing (especially titanium alloys!), and how they differ in stress cycle to failure longevity, and even how they differ in hard, sharp, spike amplitude IMPACT failure scenarios.
It would bother me if i just dropped $20K USD on a fully kitted out Dogma (or whatever their up to the second top of the line is right now?) rig knowing that if I used it as it was built to be used, I would have to replace it in less than 5 years time.
But then again, if I had Jeff Bezos type coin, and was incessantly worried about my kit being 'dated' even a slight bit style wise, I'd be dropping that much every other year or so anyway.
Really great video Olly, really good questions and answers from the experts. It's good to compare the different frame materials, and good to hear about fatigue stress levels and deflection cycles. It would be really good to do a video on tube shapes and sizes and wall thicknesses, which drives the stress and deflections, and then the forming and shape of the joints, such as the bottom bracket area, and how that can stiffen or flex the feel, and is pretty much independent of material. Great to see some engineering principles talked about!
This is the real content!. I bought a Giant Cadex CFR 4 originally it was a racing road bike ,one of the first carbon bikes ever made, but its been transformed into a fixed gear bicycle the frame and the fork are from the 90s the other components have been changed and it's still rides like a dream.. tho I always have that thought on the back of my head when im ridin, especially fast over a rough terrain, that it could actually snap in half....only the lugs are aluminium, the tubes carbon.....I hope it will last me another 30 years, fingers crossed....
Ja, I am in the same situation. My hope is that failure is not catastrophic, and simply results in a "funny" feeling ride that can be seen as small cracks. Then, assuming my vision is still good, I can detact a failed frame.
I learned two things today: The next expert Dr. Bridgewood needs to talk to is a polymer chemist and Ollie's hairdo for aerodynamic purposes.
I am loving these videos from Ollie. What's next? If I can make a recommendation... different power meter technology. Would love to see a discussion of what goes in to pedal based vs crank arm vs spindle, etc.
Look up the channel "Peak Torque", he's made several very in depth videos about the engineering behind power meters! Great channel, I believe he is an engineer in the bike industry iirc
@@benmodel5745 I do like Peak Torque's videos. I saw the one he did on Assioma - I thought it was quite interesting.
The "dead" feeling is by no means limited to pro sprinter's bikes. Here in Girona many pros (including domestiques and climbers) talk about the difference in feel between their training bike (which may do around 30,000 km in a season) and the bikes teams reserve for them to ride in races; the difference between them is more noticeable as the season progresses. When new bikes are issued at the start of the next season even the dedicated race bikes feel better to ride.
So that would suggest that 30,000 km is enough to cause significant fatigue.. That's not very much! It would mean that even your average keen amateur doing just a few thousand km a year is going to "wear out" a frame in 5 years in terms of ride feel. OK, they will be putting out less power and so the loads wil be less, but not by an order of magnitide.
@@neil7769 That's just a couple of years for some. Never saw a manufacturer mentioning this, every year the frames are 5% lighter, 3% more rigid and 6% more compliant but the fact they wear out is omitted for some reason...
@@neil7769 that is two years of riding.
@@iwanta400ftp3 Two for you about three and a half for me, doubtless 6 months for some.. ;-)
So riders complain about the frames, which is one of the things they depend on to be supplied by their teams/sponsors... Hardly a reliable source, needs some scientific backing.
Excellent work with this video. The panel and presenter both explained and asked things very very precisely and descriptively.
Very interesting! Next time it would be great to hear these two experts on fatigue and aging of metals used for bikes (steel, aluminium and titanium).
Aluminum frames will fail eventually even when not crashed. Steel and titanium frames built properly and not crashed will last a life time and more if not rusted.
I love that video and its important to take closer looks on materials and trends. Thanks for that disenchantment of those machines. Its important to know and again and again its hard to argue with other cyclists about the properties of their loved machines. Its obviously an emotional topic but when I talk to them from my point of view as a Technical Product Designer it sometimes ends as a little bit like I have insulted somebody, because I mention the lowe suitability for everyday use and that a carbon frame has to be used more careful. The people love their light and beautyful bike and I love my carbonbike as well but if I have to make a choice to have and to keep one bike for ages I would not prefer it. The use in professional sport is a total different topic because noone cares that they use one or more than one new bike every year.
Love this sort of stuff. Deep dives into bikes science are always appreciated.
I enjoyed watching both of the interviews in this videos much more than I though I would. Good job GCN.
Again, more content like this, please. Extremely interesting!
Just got a CF MTB used for a good price and felt a bit unsure about the CF part. This vid really gave me confidence, especially the gracefully failing aspect. It's really reassuring to know that your frame first will get noticeably softer and maybe start delaminating somewhere instead of just instantly cracking like a metal frame would probably do!
“It’s nice to get some interesting questions…” - Tom must field some real daft questions frequently. Top marks Ollie - great interviews and great vid 👏
Best GCN video yet and really interesting to learn from real experts in the field. I would like to add a couple of points, one is that while NDT (non destructive testing) is talked about for testing Carbon frames after a crash, this is rarely available. metals are sonorous so they can be checked by "ringing" them. Secondly Canyon (as an example) recommend changing carbon forks at six years, obviously this is a sensible compromise as they don;t know the usage but it is an expense that requires budgeting and could come to light in the event of a post crash court case.
My 19yr Madone has become more comfortable over time. I do inspections when I clean it. Still going strong. I'm not a racer, just a Marine staying fit.
Semper Fi brother
Seller fi marine I too own a trek Madone SLR 7 project one icon
I do not know a single cyclist that likes carbon at all . Even less anyone liking a bike over a 1000 quid . I see retro old Raleigh's making a comeback for the last forever fix for sixpence ..a real bicycle . Very informative post . Thankyou .
My frame's a 20 year old carbon one and it's still fine. It's kept kept dry, clean and in an outhouse away from light. It's had to be repaired once and I can tell the difference between the before and after, but it's not enough to stop me riding it.
beat you, I have a Dunlop Hotta Perimiter TT bike with Specialized tri spokes wheels on it. The bike and wheels are circa 1993 and the wheels have a 1993 sticker on them. I changed the forks for bladed MDT units because of aerodynamics as it is a TT bike but the frame and wheels have absolutely no signs of deteriation or cracking or anything else on them after 29 years. I still regularly train on the bike but now ride a Trek Speed Concept in competition with HED 6/9 wheels.
You’ll think it’s fine until the moment it fails. Rather you than me 😀
You lost the argument at “it’s been repaired once…”. It’s not fine, it’s a ticking time bomb
@@xgalvan1 the repair was because I hit the deck, that's probably the most solid part of the bike now to be honest 🤣
I like how this conversation is real informative and just on the level that someone who has no real knowledge on this subject can still follow it.
The basics of composite materials are simple to understand. Stress, strain, Youngs modulus, layup direction fibre/resin composite etc. Modelling them in finite element software in mid 90's for my thesis was a bit more challenging!
'With knowledge comes responsibility'....let's hope bike manufacturers get better acquainted with this sort of knowledge and apply it in their production.
They know it, and there’s probably a reason why they don’t take about it.
I love this format. Overall I'm very much into deep dives that deserve their name and are carefully planed and researched. Knowledge ist nice and I would guess, that many of the viewers do appreciate that kind of content.
That was the most interesting topic in a long time. Ollie, any way the average user of carbon frames can identify mentioned weaknesses before they become a safety concern? It would be interesting to talk to the industry itself about this topic and hear their recommendations.
You can get your frame x-rayed in what ever way they x-ray carbon frames..........Like Canyon does this to their frames after they get them from Asia..........the frames are x-rayed in Asia also but Canyon spent the 500,000 for their own x-ray machine............they dont want failures.........I bought a Canyon Endurace 2 months ago.
no, carbon will usually fail completely before it will show any signs of damage. it will be practically impossible for you to tell visually on a painted carbon surface.
@@adrianc6534 It really doesnt work that way,generally cracks appear first,then things go downhill from there............buying no name chinese carbon parts is asking for disaster.
@@bradsanders6954 i did too 88.000 kms eatlier!
Great content, real technical information is essential. The thing that shocks me the most is that anybody hadn’t already figured this out! Carbon bikes are throwaway consumer goods. Most quality steel frames that are already 40 or 50 years old will, if not stored outdoors, still be giving their owners a joyful riding experience after every carbon frame ever made is in a landfill.
Insightful as always! Can’t wait for other materials especially the high price Titanium which some RUclipsrs claim it’s not as strong as credited.
It's not that it isn't as strong it's that it REALLY comes down to the welding and when many ti frames are very small and very boutique the QC can be an issue but the tubing is yes basically indestructible
@@coreygolphenee9633 Welding is the weakest part of any build facts!
@@tusharbhudia9421 ya but a bad weld on steel fails differently then on Ti and Alum which tend to be immediate and catastrophic
I have a 29 year old Dunlop Hotta Perimeter TT bike with a carbon finish with 1993 carbon specialized carbon finish tri spokes tt wheels, all in perfect condition with no cracks whatsoever. There is your answer ollie, going training on it this afternoon.
But is the carbon from back then the same as today's?
@@JasonDBike I also have a modern trek speed concept i do competition on now. I bought it expecting it to be much faster because it has modern wider wheels and a slightly more aerodynamic profile and obviously lighter. The difference in speed is immeasurable and could easily be the difference between one day and a slightly better weather day,either way. I am in the same position on both bikes and that is what is important. We are being conned, I am sure !
Exceptionally high quality content. Thoroughly enjoyed it, and also the questions asked were brilliant. I'd like to know how aluminum bike frame will compare with different levels of carbon T300, T700, T1100, etc) frame, a side by side comparison on longevity and maybe for carbons, the"un-deadness" of the frame, since they won't just break so easily. Cheers
Superb. Extremely interesting. More of these in depth and technical editions please
It would be interesting to hear what a polymer scientist has to say about the resins used in carbon fiber bike frame fabrication. Especially since the effect of UV came up a few times. Is there a resin that limits UV's impact?
Paint?
The resin itself can have UV inhibitors added, but paints (including clear coats) are better. As was pointed out, they also have a limited life. Down under where the UV is strong it's a real issue.
M8 Airbus A320 Series has carbon flight controlls and I never heard about any UV degredation problem so paint does the job well. 😉
It would interesting if the Professor of nuclear materials science could explain how an RBMK carbon fibre frame can explode. I told Prof. Dyatlov that my carbon frame exploded and that there was graphite amongst the bicycle rubble on the road....he started shouting saying *_"YOU DIDN'T SEE ANY GRAPHITE because it wasn't there!"_* The dosimeter readings of the bike wreckage maxed at out 3.6 roentgen per hour, not great but not terrible either.
There is a resin that limits UV impact, but the question then is does it work with carbon fiber to make a good bike? Acrylic resins have excellent UV resistance. They aren't as tough as epoxies (keep in mind there are a lot of different kind of epoxy resins - acrylics, too).
Excelent episode. Good questions and very well documented answers. Keep up the good work.
Have used my carbon Roubaix for 14 years now. Feels like new when riding. However, am getting a new bike just now. Old frame will now be permanently strapped to my trainer. Expect 15-20 more years of use. :-)
Just curious did the bike ever fall like from standing and also ever hit roughy roads ie pot holes and no problem or any impact and still had no issue ?
@@JitinMisra who does not fall over for 14 years with cleats 😂 - and pot holes are everywhere but tires and wheels take most of the beating. Got run down by a taxi once and repairs included a new fork and 5 ribs. Frame itself amazingly still OK.
@@meibing4912 I just bought a trek fx bike that is all carbon, to upgrade from my previous bike which was aluminum with carbon fork. Gotta say the difference is amazing, on how smooth it is over bumps. But I sometimes feel paranoid on if I have to baby it. I only ride paved roads though not jumping mountain bikes
@@JitinMisra I had the same feeling/fear in the beginning. 😁Just avoid deep scratches. I recently slammed a (new) Specialized bike with 50mm carbon wheels into a massive pothole going downhill. So surprised the wheel did not even go out of tune. Good luck and enjoy!
This was a great piece of content! Knowledgeable guests answering what they can from an interested and knowledgeable host.
16:23 Tom Bahto - Senior Specialist, Materials Engineer: "There must be millions of carbon fiber bike frames out there that are 15 to 20 years old, and they are not falling apart. So by and large, I think the cycling public are pretty safe on aging carbon fiber bikes."
Because the load experience by those frame is below the limit of frame fatigue design. And most cyclist dont produce power above 400 watt that's even less than 1 horse power
@@arifazhari7598 Thats about half a horsepower.
But real horses put out multiples of 1 horse power.......HP is a measure of long term power output, not short bursts.
@@marcalvarez4890 But horses don't ride bikes... Not that I've seen anyway.
I think a follow up conversation with a polymer specialist would be very interesting if you can manage to find someone willing to talk to you
Would be cool to see a comparison or test of heavily used pro carbon bikes and carbon bikes that are new or used by amateurs. Kept thinking about the sailing industry throughout the vid. In sailing you are starting to see more older carbon components that have been frequently exposed to UV, saltwater and high loads but my understanding is that failures aren't as common as one would expect.
no boat sank as much as the trispoke broke LOL
Such an in depth informative explanation! I only have an alloy bike and I'd love to learn about their fatigue life as well.
Nice Ollie fascinating, the information goes along well with my personal experience of Carbon Fibre failure that I experienced over the 25 to 30 year of using it in cycling, in frames & components. I the aluminium idea but would if you could cover these areas with Titanium frames also?
Best I’ve seen on GCN. Keep it up Ollie👍
Great video! Can you make a like video on aluminum, titanium, and steel?
So interesting. Really great set of questions and answers. Well done Oli.
Fascinating, more of this kind of content please 👍
I value my steel bike ever more, having been educated further by viewing this video. Thank you!
We all know that it's Neo who causes the matrix to fail
I'll pay that!
As a composite glider technician... I can say, yes material softens as described... But engeniered correctly it lasts longer than any metal... I see gliders from the late 60th regularly... In snowboards you can definitely feel that deadening... Unless you buy burton, who prestress their boards and engineer that softening before hand
Really great content thank you more if this please. Great balanced view and also brilliant to see well reasoned and knowledgeable people posting in the comments, seems the sailing world has it hardest due to the external weather and storage factors. My 2 pennies worth on bikes/frames feeling dead. For those of us who trained and raced on the same bike and put race wheels on stiffness or spoke tension etc and tyres make a bike feel drastically different obv different for high power sprinter pros but a real factor
Yes, I would imagine square acres of carbon fiber composite material exposed long term to sun, wave 'crash' stresses, and salt water does not help it's longevity one bit.
I love your floor to ceiling cabinet in the background. I wish I had one exactly like it. It's the right size. 19:12
steel frames are the boss!
I agree, you can't beat a hand made steel frame.
Steel still real!
Steel can be real....ly flipping heavy too ( I ride a cheap 14kg chromoly disc commuter bike 😰)
@@richardggeorge my salsa fargo in steel is awesome!
@@richardggeorge 14 kg are not that much for a commuter bike. My hardtail aluminum MTB also weighs 14 kg.
As long as it's not hilly tires have the biggest effect, a tire with low rolling resistance (10 to 14 W) is a difference like night and day compared to a touring bike tire with 25 W
Both guys were fascinating to listen to. I look forward to the Alu chat.
Cool, so buying a pro bikes bike is pretty much going to be a expensive painting on the wall
Climber's TT bikes would be a safe bet tho especially if they're crap at TT's chances are its had naff all use.
Great video Ollie, thank you for your and your guests input on the topic.
Very informative just look after your frame 👌
I experienced UV destruction on my friend’s Orbea Orca 2009 frame about 3 years ago. Clear coat matte finish that showcased the carbon fiber.. 10 years of hot summer riding did it in. The chain stays got real punky like a sheet of plywood that had severe water damage. His bike was leaning against his garage it rolled forward and a corner of a brick pillar and a created a hole. We then poked around with fingers and started to create other holes. I had a similar type of frame at the time that I wound spray UV protective polish on as much as I could. My latest is a painted frame.
So for 99% of riders, this isn't a real issue, yeah?
Thanks for an interesting video!
Fascinating video and content very enjoyable and educational well done Ollie more of this please 🙏
I think road cyclists stress way too much over these topics, when even the roughest asphalt or even gravel wouldn't compare to the stress applied to a bike frame that of a MTB descend. Full carbon frames are also made and used on mountain bikes yet they aren't noticeably prone to fatigue wear that people complain about it to an abnormal extent. Sure, one might say those frames are more reinforced than road bike ones, but fatigue is an integral problem the entirity of the material suffers as it get exposed to deflection and small impacts, according to these experts.
On the bottom line, will YOU keep a bike for long enough that it's something to worry about? While one day the current carbon bikes will become what the collectible, vintage steel bikes of the 70s onwards are today, even if you keep your modern-day bike for decades, or you or someone buys it much down the line, you won't view it as an everyday, dependable piece of sports equipment.
Tom Batho! That’s a face and a name I haven’t seen in a few years, since the heady days of 3T Racing and the BUKC! Glad you’re doing well mate, and proper interesting info - thanks!
Next week: Muc-Off Ninja UV-Protection Polish
Excellent content. Please continue with such informative videos. Interviews like these are gold. Thanks!!