James Murphy there are a lot of Videos on this Topic. Some are useless ( but hilarious ) to be honest but the other will be helpful to quench your thirst for knowledge...
I did buy a carbon fork off eBay. Did a disc brake conversion on a Specialized Langster. I destroyed a Stans Grail ZTR rim and the fork is solid as can be.
Yep, no need to buy carbon bike, just improved CdA by... not messing with lower bars position to have lower air impact area, but lowered down drag factor by using aero shield :D s17.postimg.org/z96xdahpr/Aero_Bike_EU_front_gears_62_T_20170826_122321_for_forum_with_cop.jpg Concept so simply and cheap, that many bike companies might be not interested in it since... everyone can do this at really low cost, so they will not be able promote expensive other "aerodynamic" bikes ;) This shown aero shield is prove of concept only prototype while for 2018 my ALU bike will be much faster by using Schwalbe Durano 1.35 tyres and aero shield optimized to expected cruise speed eg. 30kph or 40kph like expensive TT bikes for more powerfull riders .
Thanks for this interesting comparison. I have been using a carbon handlebar on my carbon racebike for 15 years. I had light crashes as well and it still does its job perfectly. My gravelbike is suited with an aluminium handlebar. I think if‘s manufactured properly either of them will give you a lot of pleasure. There’s an other point which haven’t been mentioned. The aesthetics. Often carbon handlebars does have a better look and this has nothing to to with functionality. Be honest ... sometimes you just spent the money because it looks nice and it makes you pleasure, don’t you.
The feel of a carbon bar on the road is much better than aluminum as it takes a lot of the vibration out. The beauty of this video and others like it regarding carbon versus aluminum is that it makes us aware of how these materials can fail. Since we are all bike nerds I would bet the majority of us look over our bikes often for cracks and breaks. Especially after we crash or hit a pothole. It’s all about how much you can afford and more importantly we are aware of these things. Stay safe friends and if it’s carbon or aluminum it’s still a bike and that’s why we love it!!
Broke two carbon bars in accidents. One doing a sloppy trackstand another after getting bumped off my bike by a car at 40kph. Not wasting my money on carbon handlebar again just to save 50g
It happened a few years ago so I don't know the details what caused the failure. It's really dangerous though for a bar to suddenly shatter like that didn't look very good for the manufacturer. I doubt that could happen to aluminium bars(?).
@@thisandthat1233 It can happen to aluminum bars. I have 10 years of shop experience and I've seen folded bars and seatposts. Especially with ENVE, you can guarantee that it was user error, or the 1 in 2000 bars with an actual defect(no manufacturing process is 100% consistent and perfect). Fuck, Shimano had to recall Dura-Ace cranks about 10 years ago because of a bad batch of alloy. I saw two failures in person. Literally a 3p degree bend in the drive-side ALUMINUM crank arm. Dude ate shit big time. He's a master's crit racer. Not a big guy at all, just doing sprint intervals. His crank couldn't do a rotation.
Thanks for the test, Si, and my preference is aluminum. And thanks to Controltech for continuing to offer bar ends--I like straight bars on my commuter steeds but I like 'em better with bar ends.
Would love to see the impact test when you drop the bars first. My biggest fear is to damage the carbon structure resulting in sudden break. Test seems to me a little bit too far a way from reality.
Dan Connelly it happened to a friend of mine: the tape actually held the handlebar together so that he was able to see that the bar was broken but no catastrophic failure.
Exactly, if carbon were damaged, you will feel the softness, still it won't fall apart. And, of course, if there were a crash, you need to check the bike, and not only the bar, but carbon frame too.
Would have been interesting to see the impact tests after being fatigued (ie more real world appropriate) and also with lateral as well as vertical impacts (the former being more relevant to crashes, the latter to pot-holes etc) Doesn't look like Controltech were really pushing for one result over the other, if they were trying to promote carbon bars then you would have thought they'd provide a carbon bar without flared tops for the test as presumably a round bar would be more structurally sound (though then missing the aero benefits of course)
iv had a alaminium flat bar on a motocross bike break at the tripple clamp and when it goes, it goes. it was if somebody lazer cut the bar off instantly. compared that to how a carbon bar splinters like a tree branch. id rather have carbon because both your hands will be attached to the bike still. when the ally bar went on me, i fell straight off the back of the motorbike as it was the left side that broke off which lead to me grabbing a hand full of throttle trying to hold on with the right.
Carbon may be "stronger", but every single carbon handlebar and carbon stem I've used has been noticeable flexier than an aluminum handlebar and stem when out of the saddle and hammering. That flex makes me feel like I'm losing energy and not always in control. They're definitely more comfortable on longer rides, however. EDIT: I should mention the bars/stem since I'll probably get flack... They were Ritchey WCS carbon combo and FSA K-Force carbon combo. I settled on aluminum 3T Ergonova bars and ARX stem, which are noticeably stiffer. I've tried many other bars/stems but these are what I've used in last five years; don't think it's fair comparing 15 year old technology to todays.
Is anyone else sceptical about the fact that they tested an aero carbon handlebar? Aren't standard carbon handlebars a bit stronger since they are round instead of flat?...
a lot of carbon bars now are going aero, that's an allure of going carbon, right? Why would I want a round carbon bar when I can get it aero? It's a valid test.
My S Works aerofly carbon bars cracked during use, near (but not on) brake lever clamping area. It started at the hole where the internal cables went in. Luckily I spotted it when fitting new tape, it had gone 3/4 of the way round. I’ve replaced them with aluminium ones, spoils the look a bit, but so would an about to happen death crash.
I'd like to see a long term reliability test with real world conditions, adding in salt (the influence of sweat) and rain and sunshine to see how those factors impact each material.
Hahahahaha Seriously though that depends on the particular aluminum allow. A 7075 bar will be stronger till yield. However a 4130 steel bar will absorb more energy for sure.
@@FLMKane That's an interesting aspect of Alu over carbon. All alloy used within the cycling industry uses a T6 heat treatment process, I won't go into the heat quench timings because it's boring but, the ideas is that elements are present in different alloys to add different characteristics depending on application which translates to different weaves in the carbon world, 1K-12K, UD and so on. It is said that if your going to go with Carbon rims then go for disc or tubs due to the construction behind the braking surface, ie, Tub over clincher. Steel on the other hand is an, oddly, more complex kettle of fish. With F1 using 531 before carbon mono and with Columbus and Reynolds leading the way when it comes to bi-axle and trumpet tubing. With the testing process and ISO standards and with 10N equating to around 1KG for your everyday Joe, if your the sort of rider that puts down 500-1KW on your normal ride then a non branded frame would be questionable but....and there always is, if you haven't got tree trunk legs then a Chinese frame/grey import is worth looking at. I had ridden a Himod Cannondale for a few years and then bought a non branded frame as a winter ride, once built and dialed in it felt better than the Cannondale. I really wanted it to be crap so I gave it some abuse, this was around two years ago. I still have it and it's as sweet as the day I bought it, I've even bought a Grey imp, F8....just as nice to ride. (There has been some testing and frames being cut up in the world of Pinarello and their spec is frames being made from 1K weaves but having cut one straight down the middle they found 3K within and the outside layer being 1K, this is from the horses mouth and not one of those BS myths. Pinarello frames are finished in Italy with a lot of top end brands having their frames constructed in the same factories as you "no good" chinese frames. To conclude, If you pay your wack then you can have a nicely painted frame with stickers on, if you haven't the wack, then you can have the same frame with no fancy paint or stickers. I can tell this is going to open the biggest can of worms but the proof is in the riding. I've been blanked by other roadies due to riding a unbranded ride, it doesn't matter what you ride as long as you ride.
When an aluminum part fails, it is a lot of cheaper to replace. Plus aluminum manufacturing is less prone to manufacturing defects especially if there are no welds involved. Also, i haven't seen an aluminum part fail during a race without it being involved in a crash.
I watched this video because I wanted to hear Si say "al-you-MIN-ium". :) But seriously--I've ridden carbon and AL bars and crashed both--never broken a bar but broke some wheels. I will say that I prefer carbon bars for the dampening and a reduced galvanic corrosion potential with the steel shifter clamps. It's not a commonly discussed issue but I probably sweat more than most folks. I didn't realize it was an issue until I snapped off the drops on an aluminum bar after the corrosion ate through it. With carbon bars, the steel clamp becomes the donor and they rust away. After 2-3 years I replace the clamps.
For the price of 1 carbon bar i can buy 4 alloy bars. aluminium: 450.000/500.000 cycles x4 = 1.800.000/2.000.000 carbon: 600.000/800.000 for the same price alloy can last more than 2x longer. Not hating Carbon, just for the price alloy would be a better option.
the reason professionals use alloy over carbon is that in the event you do have a crash where all the impact is imparted on the bars(I have personally experienced that my self) carbon cracks, where as alloy bars will bend, even if your bar is one half of a pretzel you can still ride home(if your still able to stand at that point) or continue the race where as a carbon bar will split in two, this is called shearing force, this shearing force is the reason the carbon bars cracked on the drop test, ductile alloy materials will always have a greater shearing force than super strong materials like carbon.
That's the first thing that I thought when I heard him ask why do pros still use aluminum when carbon is lighter. They aren't exactly having a hard time staying down at the UCI lower limit, so any real or perceived benefit is worth keeping the aluminum bars.
Weren't there a couple of videos this last year of racing where a CF stem or steerer tube failed on the rider in a race? And video of a CF aerobar fail in a TT? Maybe the handlebars are likely to not fail in normal use/abuse for either Al or CF. But the failure mode of CF... oy.
No chance- after a crash pros change bikes- end of. Its about ride ability and shape- and the weight limit- most pro bikes are well under this so heavier bars dont matter. I love carbon bars- if you have a big crash and dont change your bars anyway you are a moron!
That us d to be the case. Some of them now just use it to give their mechanic a easier time so they don't have to weigh it down as much. They mostly now ride carbon bars due to that alot of them now ride proprietary bars that each model need to be more aero. If stress and damage was a concern all sprinters would be on aluminum bars rather than carbon ones. Especially the likes of Caleb Ewan, Mark Cavendish, Peter Sagan.... You get the point. Even all the track sprinters use carbon bars.
A good drinking game is Chinese "Russian" roulette, order the cheapest Carbon bar you can find online, then head down a massive hill at full speed, over 50mph is best, do this in a group of at least 5... The person that survives wins..
Top end carbon frames and parts for companies like Trek, Canyon, Pinarello are all made in China... If you buy the very cheapest, you get what you pay for, but country of origin has nothing to do with it. At medium price point Chinese carbon fiber parts are better than US/Europe made ones at a significantly lower price.
Almost everything is made in China. If it says 'Made in Taiwan' on it, it was probably only sprayed and finished there. So laughing at Chinese products is a bit weak when you consider all the stuff you think is better Italian and Taiwanese isn't.
This is a pretty timely video. I just taking a break from studying for an exam in the exact content. I guess that means this counts as study and I can take a longer break.
Although Alu bars have less fatigue strength they are also cheaper so you can change them more regularly. But to decide which one to choose you need to know what kind of forces go through the bar during use. This video has only given us half the information we need.
After buying a carbon seat post at a steal, I'm once again hooked! Looking to replace aluminum bars by control tech with carbon ones. The difference in ride quality is night and day. The new bars were also a steal at $99, honestly I don't care if they break b/c that level of comfort & lightness is totally worth it. Anyone looking to do significant miles on a bike should be looking at carbon components.
Some scientific studies have been done on non-round rings and so far it wasn't scientifically proven with statistic significance that they are better, or indeed worse. Granted these studies have flaws like small size samples and limited experiment time. So for now it comes down to feeling good or not with them.
Chris Froome's osymetric chainrings doesn'tt need scientific proove - he says they give him advantage and he is wondering why other doesn;t use them :D I use in my road bike aka Froome laser cut three oval chainrings 34/52/62 in MTB aluminium bike s17.postimg.org/z96xdahpr/Aero_Bike_EU_front_gears_62_T_20170826_122321_for_forum_with_cop.jpg and I feel huge difference in fighting sweet spot when compared to classic round chainrings no matter flat or while climbing ;) While climbing at lower RPM i used to slide in sweetspot back by pulling SPD blocks and use its smaller diameter to easier increase average RPM, while in the case of classic chainrings one had to change gears to be able keep going up hill. I believe in Chris secret is how he managed to use their osymetric chain rings, and nobody will know what he exactly does since he shows only average cadence and detailed timing within one full 360 deg chainring rotation is not published as I know - Ibelieve in only after race video analysis could reveal such details by frame to frame anlysis of Froome rotation timing - probbaly it is constant rotation speed within rotation at high cadence, but at lower while standing on bike it might be different, I guess.
I broke my back in a bike accident a few years ago and can't ride crouched down any more. Could I put BMX bars or similar on my ancient Kettler frame to help (I'm also 6ft6) and how would they affect the riding? I currently suffer badly after the 20-30 miles I ride a day, and have two centuries in 2 days next April, then a 2 day break until another pair of centuries, so I won't be able to lean for most of it, but speed isn't too much of an issue. I will add a huge thanks to GCN for relighting my passion for cycling too - now I go everywhere with my son in the trailer, rather than taking the bus locally, so thanks!
You can design either material to any strength you like given there is no weight limit specified and that doesn't matter whats over. I'm more worried about the failure modes. Metal cracks are usually obvious and visible on the surface be it coming from impact or fatigue; carbon on the other hand leaves doubt lingering in my mind even if it looks fine on the surface after an impact. For that reason I stuck with alloy.
its probably good to point out that aluminum is prone to failure due to corrosion brought on over time from sweat. if one has a high sweat rate and isn't changing bar tape often then there can be a catostrphic failure. i had a friend go down and break 5 ribs during a crit due to his bars failing. He is kind of a heavier rider.
Crashing with an aluminium bar:"Oh it seems fine, lets ride home." A few miles down the road :" Oh Oh ." Aluminium breaks without warning, happened to me twice, switched to steel on my MTB and to Carbon.
Accident impacts never occur in the direction that the force was applied in this test. It generally happens sideways, which is the weakest part of a handlebar because forces while riding are never applied that way.
Typically, a hardcore rider would crash many times far before either the aluminium and carbon bar fail from fatigue. And speaking from my local racing experience, there's like a 50% chance of a carbon bar cracking upon impact in a crit... And man, that happens almost every week to some poor chap. Also, saying you could ride the crack that formed from the 60cm impact out is plain irresponsible. The next time you hit a pot hole you are going to hit all your teeth out.
許嘉宇 I think the point he's making is that it doesn't snap in half, so you can ride out of the pothole and not crash- definitely not meaning "keep riding it" !!
What the hell kind of crit are you doing where there are that many broken handlebars? I race and have seen only a couple of times seen cracked or dented handlebars
I know he meant you can ride home. But I am saying that is a very dangerous thing to do when you have 2 big ass crack on your handlebar. Any responsible manufactur would tell you to stop riding immediately and take a bus home or something. Racers in my area are rich so most of them run carbon bars. It really doesn't take much to crack an ENVE, 3T or ZIPP. Sometimes a slide out when cornering will do. Dropping your bike when you stopped for coffee will also do...
I'd stick with aluminium for the insanely lower price, specially in my country where road bikes are super expensive and I still couldn't buy an entrance level one. That love for Road Cycling will never let me have money to spare.
The crash test missed a very important factor for aluminium -- it fatigues at very low stress levels and the micro-damage from that fatigue is cumulative. This means that the alloy handlebar that withstood 80 cm of impact when new, may be damaged at a significantly lower level after it's been in use a while. This cumulative fatigue characteristic of aluminium alloys is one of the reasons why engineers must build in much greater safety margins into their alloy designs. By comparison, steel, titanium and composite carbon do not have the same cumulative fatigue problem. To factor the effect of cumulative stress into your drop test, you would want to conduct the drop test on handlebars that have first been pre-stressed with the fatigue test. Another factor that was overlooked in these tests was the kind of reinforcement provided in the composite carbon handlebar. The one tested did not appear to be reinforced for aerobar use. I use aerobars and my composite handlebars are all reinforced for them. This means the handlebar manufacturer increases the width of the center portion of the handlebar that can safely accept a clamping force. This is done so aerobar brackets can be added on either side of the stem. These type of composite handlebars might not fail as early as yours did in the crash test. It would be interesting to see what drop height they could handle.
What about a carbon handlebar that weighs the same as the aluminum one? There wouldn't be any weight savings, sure but would it handle the impact tests even better than the aluminum one?
Carbon both flat bar and drops. Have being riding carbon flat bar on my commute/utility tourer for 8 years, a lightweight 120g job made by Bottechia, I've been rear ended in a hit and run, a spill when a numpty kid ran into me in the middle of the road and a spill on iced over compacted snow down the hill to the supermarket (my fault going too fast). Not a murmour, nor to the carbon forks nor the carbon stays, oh yeah,I'm 102kg on a good day and I carry 20kg+ loads reasonably often and I'm not gentle with the bike. (Spesh globe pro). Just bought some 'PRO' flat bars to go on my adventure/gravel rig, I use Modolo Curviussima on my CF racer. I'm still running TIME carbon composite forks from 1991. Make your own mind up but CF bars all the time for me, I'd never go back to alu, too stiff and not as robust.
I stay with aluminum because it stands a higher chance of surviving a crash. Assuming the rest of the bike is fine, I can finish a ride with a bent bar, but likely not with a totally broken one.
Aluminium bars wont bent that much, they break and when they break it happens fast and violently. So you have two options with an AL-bar: it doesnt break or it breaks so hard that you will hit the ground for shure. Happend to me twice. With an carbon bar, it doesnt break that violently, it is like wood, it will buckle and get flexible but in most cases the bar will remain in one piece and you wont crash into the ground. I will stay with carbon as it is the safest option.
If the carbon composite structure is so much lighter why don't do the manufacturers increase the wall thickness to match the weight of the aluminium counterpart? It could be much more stronger and the inner diameter doesn't look that much important other than at the very end of the tube (where end plugs can be used).
probably bc the carbonfiber still break if the force is aplied the wrong way so there is little to no point in making them stronger to forces in one dirrection also the prise would go up be a lot
The carbon composite handlebar is already way stronger than it needs to be. The impact test they performed was way more punishing to the handlebar than any vertical impact it would ever experience on a ride, due to the lack of cushion one would otherwise get from their front tyres. That being said, I think they could've optimized the profile of the horizontal sections a bit better. The handlebars are basically cantilever beams. You want the handlebar to be as uniformly stressed as possible for maximal performance/weight. A triangular width taper with no depth tapering is the strongest cantilever beam gram-for-gram, and this would be easy to achieve with carbon composites. Also, the thinner the walls are relative to the depth of the cross section, the closer the inside edge and outside edge are in bending stress. So you can go with a deeper wing section and use thinner walls to get the same strength with less material, at the expense of increased frontal area and drag. All engineering is a compromise, and the exact solution the engineers decide on depends on the intended application. For example, a time trial handlebar should be ultra slender in profile at the expense of extra dead weight, while a hill climb handlebar should be ultra deep and thin-walled to save every gram possible without compromising rigidity.
I see a lot of comments about steel bars here but how's about titanium people seemed to have forgotten ti bars If done properly as light or lighter than an alu alloy bar but with better damping and fatigue life than steel, I live by the coast so the fact it doesn't corrode either is a big bonus too.
I had a wicked 40kmh crash shortly after I got my current race bike, I slid on top the bike into a curb, aluminum bars bent a little bit, I just cranked them back and they're still good 3 years later, I have serious doubts carbon bars would have survived that...it's one thing to test impact where the bar can spring around like that with a weight on the end, it's another to hit an immovable object at 40kmh with a 90kg rider on top of it...
Yes, because Aluminum is a ductile material, however, in these tests failure isn't considered minor yielding. Granted, I'd consider the change in shape to be small enough to keep riding, but if you've had that much impact, the handlebars won't be what I'm concerned about.
What about combination of fatigue and stress testing? How much does lifespan of both carbon and aluminium decreases after for example hitting a pothole?
It’s not impact stress that makes aluminum stronger it’s the fact that it can take more weight and that it will give and bend the carbon just snaps the aluminum will just bend.
In terms of years of regular use by a rider who rides, say, 10-20 miles per day, how do these measures translate? Is a year if riding like 100,000 stress tests?
I'm a big guy (6'4", 260 lbs). I rode DH for a decade, before coming back to more AM riding. I'm running a set of Oxive carbon fiber wheels. I am amazed at how strong they are. The wheelset weighs just over 1600 grams, and they are STRONG. I had a crash this summer, moving at around 15 MPH, where I stuffed the front wheel sideways into the ground, full on 90 degrees like. I took a beating. My bike took a beating (I twisted my stem 90 degrees on the steerer tube, the brake calipers on both ends of the bike had to be realigned, and my rear thru axle got twisted weird in the frame somehow). My wheels were perfect. Not a mm out of true. As a big guy, I have a history of destroying rims. My carbon rims with a season of riding have a few nicks and scratches, otherwise they are perfect.
Time is not a friend to carbon; the resins can/will age (dry out - especially with temp changes & humidity fluctuations, again over time), which would dramatically change it's results for both tests. Also, the impact to worry about with carbon is not so much the load spread over the length of the bar, but an impact on a specific spot on the handlebar. Say a one inch tube striking the top bar just outside where it attaches to the stem (as what might happen in a peloton crash) - there also the carbon will have a significantly less impact resistance. They are sweet, but not worth the minor weight penalty for me (or even most of the pros who don't even have to pay the extra out of their own pocket)
So in the breaking-test you compare an aero-handlebar with a normal round handlebar? You would better compare apples with apples and pears with pears. What about compairison of stiffness or comfort. I'm currently deciding between two handlebars for my gravel-project. Alu: 233g / 80 Euro. Carbon 190g / 260 Euro. OK, 40 gramm ist 40 gramm, and if you don't know where to safe them, you perhaps need this carbon handlebar. But if you go out for a ride these 40 gramm won't bother you. So for me would be verry interresting, what about stiffness and comfort - maybe also which ist stronger - but only for the same shape and dimension of handlebar.
I don't think the argument is really understood here. Everybody knows carbon fiber is stronger as it's engineered to be, but only in an "as intended" to be used circumstance. You rightly pointed out that the aluminum would be stronger in a crash, and THAT is why people choose aluminum (well, that and the price tag). Coming from the world of mountain biking I've seen tons of carbon parts having to be trashed because of damage from crashes where an aluminum part would've fared just fine. Case in point is my aluminum Santa Cruz Nomad. The things I've done to that frame.... yet I've not had to replace it because I've scratched it.
What about the issue of damage visibility? Isn't it more of an issue with carbon having invisible damage where as alloy it's more obvious to the naked eye?
Dude or rather GCN folks the problem is with the counterfeiting of carbon handle bars being sold online or even at your friendly neighborhood bike store for cheap that use bike people just cannot over look e.g.: $50 versus $350 for a handle bar.. Besides the problem with pro peloton usage is that the mechanics cannot see the cracks within the carbon you easily saw in your test after a crash. Anyways the general rule is to replace the carbon bar after an accident and replace the carbon bar after say 2 years of use. My Aluminum bike down tube finally cracked and then slowly grew longer after 13 years of use until I could tell there was a problem e.g.: the chain shifting up or down a cog on hard accelerations because the frame flexed. I really do understand how a Pro cyclist can ride a bike and tell when the frame characteristics have changed. When carbon frames go out of speck why they just catastrophically fail it is my understand. Recently my carbon fork made a crack sound while traveling down hill say 20mph after hitting a pothole. After visual inspection I could see nothing wrong..no cracks. But it is my understanding that inside the fork voids or wrinkles of the carbon fibers can buckle and peel away weakening the fork blade. 5.8 Kilograms = 12.7868112 Pounds *2 = 24 pounds...tire and wheel and fork deflection will allow this # to reflect the actual weight of the rider that may weigh 280 pounds. 36 Centimeters = 14.1732283 Inches 48 Centimeters = 18.8976378 Inches 60 Centimeters = 23.6220472 Inches 72 Centimeters = 28.3464567 Inches 84 Centimeters = 33.0708661 Inches
Forgive my ignorance, but what about stainless steel bars? I imagine it depends on the composition of the steel but is there any argument to be made for steel?
In a crash, its much harder to determine the extent of the damage to carbon bars vs. alu. I typically continue to ride the same bars post crashes so for that unknown multiple crash factor... I ride alu for road and mtn.
In the stress test, is the stem standardized? Because the way the (stress) machine works, alternately pushing down on the ends of the bar, how much of that the bar could take is, in part, dependent upon how much flex is in the stem. The more rigid the stem, the more stress is put on the bar (because a flexing stem absorbs some of the energy, while a stiffer stem absorbs less, allowing the bars to take the energy). It would be better to mount the bar directly to a rigid upright, so the maximum amount of force from the machine goes into the bar. Maybe also push down on both ends of the bar at the same time, to maximally stress the bar, rather than inducing torsion into the mount, thereby eliminating a variable.
What information actually matters and how much? Most bikers are not pros much less racers. For realistic stress from usage, and durability should one choose everything aluminium? Do we ever get to customize all components in bikes under £1500? They come packaged as one product minus pedals unless one wants to replace and upgrade. Any suggestions?
I can say yes. AL can be resistant to virtually any force vector (won't say absolutely any force vector, to play it safe), but for carbon, only in its intended ones.
I will always go with Aluminium because I want crash strength. I've bent 6 seatposts on a mountain bike and quite a few handle bars in my day and I would much rather have it bend than shatter. Thanks.
So why is it that both of my local bike shops that have been around for a very long time, (when steel was the frame of choice) that these shops are seeing far more failures due to fatigue with carbon fiber bars then they ever saw with aluminum bars? They also are seeing more CF bars being broken in accidents as well, but that was pointed out with this video. Now there is some debate as to what is causing CF bars to fail, the mechanics were also saying that there may be some problems that look like fatigue failures when in fact they were operator installed error that over torqued the bars and the stem clamps crushed the fiber just a bit and over time they broke. There's even controversy that some mechanics either don't know the exact torque setting to use or the company with the bars gave wrong torque information. Something that never was even remotely considered being a problem with AL bars. The mechanics I spoke to about this all said they would never use CF bars, and one went as far to say he would never buy a CF bike because they're seeing a higher failure rate of CF frame as well vs other material they currently sell or use to sell, but that's another debate. To be fair there was one mechanic who does some state racing, his race bike is all CF including the bar, but when he's not racing he uses another bike for training that has AL bars, but that as he said comes down to weight and on the racing bike he's cutting weight as much as he can.
The impact test is nor fear because the handle bar shape is not the same. The place where the carbon one cracked was flat for aerodynamic reasons compared to a cylindrical one on the aluminium one.
It also depends on the stem aswell. Mixing aluminium components wih carbon can reduce the lifespan of the part especially in winter . This is because the salt reacts with both materials and makes a battery which corrodes the carbon.
Did you test Titanium bars? If not would be interesting and they are available at least in straight and riser for MTB. Do a search of Carbon fiber handlebar breaking to see plenty of videos of breaking handlebars. Have seen in professional road racing and drop bars as well.
So, why did you use a round aluminum bar and an aero with internal cable route carbon bar for the impact test? Possible results were stacked in the aluminum favor by the shape of the bar. For the comparison test to be reliable the bars would need to be the same shape.
don't have any carbon on my MTB anymore. Two seatposts snapped. Both with no external sign of wear. And no , I'm not a fat bastard.\just used the bike as it was designed.
If I build an MTB (I plan to build a trail bike once I dive into MTB riding), it'll be carbon-free too. After all, it's supposed to be a fun bike, not a bling bike.
The weight difference on those bars is 55 grams, yielding weight savings at probably >4 dollars per gram. The aero bar showed earlier is much more than 169 grams.
How about testing some eBay Chinese carbon bars.
Scott Paciorek how about no?!
I'd like to see them tested too. Curious.
James Murphy there are a lot of Videos on this Topic. Some are useless ( but hilarious ) to be honest but the other will be helpful to quench your thirst for knowledge...
I did buy a carbon fork off eBay. Did a disc brake conversion on a Specialized Langster. I destroyed a Stans Grail ZTR rim and the fork is solid as can be.
China make the best carbon in the world (outside a F1 team)
Carbon can cause huge cracks to your wallet.. That is an undeniable fact 🤣🤣🤣
Aluminum is cheaper in most cases. And I think it's often good enough for amateur racers or people who just ride for fun.
Too each their own I guess.
Onypop yeah...this is my case.
Yep, no need to buy carbon bike, just improved CdA by... not messing with lower bars position to have lower air impact area, but lowered down drag factor by using aero shield :D s17.postimg.org/z96xdahpr/Aero_Bike_EU_front_gears_62_T_20170826_122321_for_forum_with_cop.jpg Concept so simply and cheap, that many bike companies might be not interested in it since... everyone can do this at really low cost, so they will not be able promote expensive other "aerodynamic" bikes ;) This shown aero shield is prove of concept only prototype while for 2018 my ALU bike will be much faster by using Schwalbe Durano 1.35 tyres and aero shield optimized to expected cruise speed eg. 30kph or 40kph like expensive TT bikes for more powerfull riders .
Or bike to work
Thanks for this interesting comparison. I have been using a carbon handlebar on my carbon racebike for 15 years. I had light crashes as well and it still does its job perfectly. My gravelbike is suited with an aluminium handlebar. I think if‘s manufactured properly either of them will give you a lot of pleasure. There’s an other point which haven’t been mentioned. The aesthetics. Often carbon handlebars does have a better look and this has nothing to to with functionality. Be honest ... sometimes you just spent the money because it looks nice and it makes you pleasure, don’t you.
The feel of a carbon bar on the road is much better than aluminum as it takes a lot of the vibration out. The beauty of this video and others like it regarding carbon versus aluminum is that it makes us aware of how these materials can fail. Since we are all bike nerds I would bet the majority of us look over our bikes often for cracks and breaks. Especially after we crash or hit a pothole. It’s all about how much you can afford and more importantly we are aware of these things. Stay safe friends and if it’s carbon or aluminum it’s still a bike and that’s why we love it!!
Broke two carbon bars in accidents. One doing a sloppy trackstand another after getting bumped off my bike by a car at 40kph. Not wasting my money on carbon handlebar again just to save 50g
I've crashed at 40mph multiple times. My carbon bars have always been fine. The only bar I've damage was an alloy bar in shipping
A friend of mine has broken ENVE mtb bars without even crashing. No interest in carbon bars here aswell.
@@thisandthat1233 99/100, that happens from over-torquing(stem or even brakes/shifters), or from really shitty/crooked faceplate install.
It happened a few years ago so I don't know the details what caused the failure. It's really dangerous though for a bar to suddenly shatter like that didn't look very good for the manufacturer. I doubt that could happen to aluminium bars(?).
@@thisandthat1233 It can happen to aluminum bars. I have 10 years of shop experience and I've seen folded bars and seatposts. Especially with ENVE, you can guarantee that it was user error, or the 1 in 2000 bars with an actual defect(no manufacturing process is 100% consistent and perfect). Fuck, Shimano had to recall Dura-Ace cranks about 10 years ago because of a bad batch of alloy. I saw two failures in person. Literally a 3p degree bend in the drive-side ALUMINUM crank arm. Dude ate shit big time. He's a master's crit racer. Not a big guy at all, just doing sprint intervals. His crank couldn't do a rotation.
Thanks for the test, Si, and my preference is aluminum. And thanks to Controltech for continuing to offer bar ends--I like straight bars on my commuter steeds but I like 'em better with bar ends.
Wow...ControlTech lives. They used to be like 'the' brand to go to back in the '90s. Glad to see they're still around.
Would love to see the impact test when you drop the bars first. My biggest fear is to damage the carbon structure resulting in sudden break. Test seems to me a little bit too far a way from reality.
Control Tech Props for such stress testing and demo of safety for riders and their most critical piece on their bikes!!!
A challenge with the carbon is if the crack is under the tape it might go unnoticed, leading to catastrophic failure later.
Dan Connelly it happened to a friend of mine: the tape actually held the handlebar together so that he was able to see that the bar was broken but no catastrophic failure.
Exactly, if carbon were damaged, you will feel the softness, still it won't fall apart. And, of course, if there were a crash, you need to check the bike, and not only the bar, but carbon frame too.
Would have been interesting to see the impact tests after being fatigued (ie more real world appropriate) and also with lateral as well as vertical impacts (the former being more relevant to crashes, the latter to pot-holes etc)
Doesn't look like Controltech were really pushing for one result over the other, if they were trying to promote carbon bars then you would have thought they'd provide a carbon bar without flared tops for the test as presumably a round bar would be more structurally sound (though then missing the aero benefits of course)
iv had a alaminium flat bar on a motocross bike break at the tripple clamp and when it goes, it goes. it was if somebody lazer cut the bar off instantly. compared that to how a carbon bar splinters like a tree branch. id rather have carbon because both your hands will be attached to the bike still. when the ally bar went on me, i fell straight off the back of the motorbike as it was the left side that broke off which lead to me grabbing a hand full of throttle trying to hold on with the right.
Oh snap, GCN is raising the bar and providing us the best test of stress, bar none. Can you handle it?
Too much pun. Stop! ;D
It cracks me up that some get bent out of shape about this stuff. Glad GCN taped this, hands down it's good info.
Yea, some people just need their ends plugged.
Hahaha
Too much nutrients going to your brain... :)
Watching all these videos about carbon my conclusion is that carbon is disposable, a very very very expensive disposable thing
what's the actual vibration dampening capacity of those handlebars? Is it something actually noticeable?
Carbon may be "stronger", but every single carbon handlebar and carbon stem I've used has been noticeable flexier than an aluminum handlebar and stem when out of the saddle and hammering. That flex makes me feel like I'm losing energy and not always in control. They're definitely more comfortable on longer rides, however.
EDIT: I should mention the bars/stem since I'll probably get flack... They were Ritchey WCS carbon combo and FSA K-Force carbon combo. I settled on aluminum 3T Ergonova bars and ARX stem, which are noticeably stiffer. I've tried many other bars/stems but these are what I've used in last five years; don't think it's fair comparing 15 year old technology to todays.
Is anyone else sceptical about the fact that they tested an aero carbon handlebar? Aren't standard carbon handlebars a bit stronger since they are round instead of flat?...
Anthony HT i was thinking exactly the same. The shapes of the bar absolutely changes the integrity of the structure. Retest!!
Yep a round bar would be much less likely to buckle.
Agreed.
i agree with you.
a lot of carbon bars now are going aero, that's an allure of going carbon, right? Why would I want a round carbon bar when I can get it aero? It's a valid test.
The more you watch GCN the knowlegable you become. Thanks GCN
My S Works aerofly carbon bars cracked during use, near (but not on) brake lever clamping area. It started at the hole where the internal cables went in. Luckily I spotted it when fitting new tape, it had gone 3/4 of the way round. I’ve replaced them with aluminium ones, spoils the look a bit, but so would an about to happen death crash.
I'd like to see a long term reliability test with real world conditions, adding in salt (the influence of sweat) and rain and sunshine to see how those factors impact each material.
I'm more worried about the damage from when the bike falls on it's side then from a pot hole
Carbon or aluminium bars?
My choice??.. definitely chromoly .. 😂😂
Hahahahaha
Seriously though that depends on the particular aluminum allow. A 7075 bar will be stronger till yield. However a 4130 steel bar will absorb more energy for sure.
@@FLMKane That's an interesting aspect of Alu over carbon. All alloy used within the cycling industry uses a T6 heat treatment process, I won't go into the heat quench timings because it's boring but, the ideas is that elements are present in different alloys to add different characteristics depending on application which translates to different weaves in the carbon world, 1K-12K, UD and so on. It is said that if your going to go with Carbon rims then go for disc or tubs due to the construction behind the braking surface, ie, Tub over clincher.
Steel on the other hand is an, oddly, more complex kettle of fish. With F1 using 531 before carbon mono and with Columbus and Reynolds leading the way when it comes to bi-axle and trumpet tubing.
With the testing process and ISO standards and with 10N equating to around 1KG for your everyday Joe, if your the sort of rider that puts down 500-1KW on your normal ride then a non branded frame would be questionable but....and there always is, if you haven't got tree trunk legs then a Chinese frame/grey import is worth looking at. I had ridden a Himod Cannondale for a few years and then bought a non branded frame as a winter ride, once built and dialed in it felt better than the Cannondale. I really wanted it to be crap so I gave it some abuse, this was around two years ago. I still have it and it's as sweet as the day I bought it, I've even bought a Grey imp, F8....just as nice to ride. (There has been some testing and frames being cut up in the world of Pinarello and their spec is frames being made from 1K weaves but having cut one straight down the middle they found 3K within and the outside layer being 1K, this is from the horses mouth and not one of those BS myths. Pinarello frames are finished in Italy with a lot of top end brands having their frames constructed in the same factories as you "no good" chinese frames. To conclude, If you pay your wack then you can have a nicely painted frame with stickers on, if you haven't the wack, then you can have the same frame with no fancy paint or stickers.
I can tell this is going to open the biggest can of worms but the proof is in the riding. I've been blanked by other roadies due to riding a unbranded ride, it doesn't matter what you ride as long as you ride.
Mine? Titanium!
When an aluminum part fails, it is a lot of cheaper to replace. Plus aluminum manufacturing is less prone to manufacturing defects especially if there are no welds involved.
Also, i haven't seen an aluminum part fail during a race without it being involved in a crash.
No handlebars were harmed in the making of this video.
I watched this video because I wanted to hear Si say "al-you-MIN-ium". :) But seriously--I've ridden carbon and AL bars and crashed both--never broken a bar but broke some wheels. I will say that I prefer carbon bars for the dampening and a reduced galvanic corrosion potential with the steel shifter clamps. It's not a commonly discussed issue but I probably sweat more than most folks. I didn't realize it was an issue until I snapped off the drops on an aluminum bar after the corrosion ate through it. With carbon bars, the steel clamp becomes the donor and they rust away. After 2-3 years I replace the clamps.
For the price of 1 carbon bar i can buy 4 alloy bars.
aluminium: 450.000/500.000 cycles x4 = 1.800.000/2.000.000
carbon: 600.000/800.000
for the same price alloy can last more than 2x longer.
Not hating Carbon, just for the price alloy would be a better option.
No point to go for carbon unless you are professional race cyclist.
Mr. Wizeguy for Handelbar Aluminium will do. Even pros don’t use carbon
Carbon is better for a tt deck though
lol
Unless you find a good pair on clearance that saves weight
Way to be a buzz kill, everyone would be driving a Prius if we all thought like that
the reason professionals use alloy over carbon is that in the event you do have a crash where all the impact is imparted on the bars(I have personally experienced that my self) carbon cracks, where as alloy bars will bend, even if your bar is one half of a pretzel you can still ride home(if your still able to stand at that point) or continue the race where as a carbon bar will split in two, this is called shearing force, this shearing force is the reason the carbon bars cracked on the drop test, ductile alloy materials will always have a greater shearing force than super strong materials like carbon.
That's the first thing that I thought when I heard him ask why do pros still use aluminum when carbon is lighter. They aren't exactly having a hard time staying down at the UCI lower limit, so any real or perceived benefit is worth keeping the aluminum bars.
Weren't there a couple of videos this last year of racing where a CF stem or steerer tube failed on the rider in a race? And video of a CF aerobar fail in a TT?
Maybe the handlebars are likely to not fail in normal use/abuse for either Al or CF. But the failure mode of CF... oy.
No chance- after a crash pros change bikes- end of. Its about ride ability and shape- and the weight limit- most pro bikes are well under this so heavier bars dont matter. I love carbon bars- if you have a big crash and dont change your bars anyway you are a moron!
That us d to be the case. Some of them now just use it to give their mechanic a easier time so they don't have to weigh it down as much.
They mostly now ride carbon bars due to that alot of them now ride proprietary bars that each model need to be more aero.
If stress and damage was a concern all sprinters would be on aluminum bars rather than carbon ones. Especially the likes of Caleb Ewan, Mark Cavendish, Peter Sagan.... You get the point. Even all the track sprinters use carbon bars.
seanvityaz
What about a Thompson titanium bar?
A good drinking game is Chinese "Russian" roulette, order the cheapest Carbon bar you can find online, then head down a massive hill at full speed, over 50mph is best, do this in a group of at least 5... The person that survives wins..
😂
I like competitions where the 1st price is just surviving...
Not.
Lol ok I'll give you a head start
Top end carbon frames and parts for companies like Trek, Canyon, Pinarello are all made in China... If you buy the very cheapest, you get what you pay for, but country of origin has nothing to do with it. At medium price point Chinese carbon fiber parts are better than US/Europe made ones at a significantly lower price.
Almost everything is made in China. If it says 'Made in Taiwan' on it, it was probably only sprayed and finished there. So laughing at Chinese products is a bit weak when you consider all the stuff you think is better Italian and Taiwanese isn't.
Spoiler it’s wood
Nice vids guys you motivated me to start riding more... Like A lot more. Keep it upp
Great stuff Kobe!
This is a pretty timely video. I just taking a break from studying for an exam in the exact content. I guess that means this counts as study and I can take a longer break.
*winning*
Hopefully you don't fail, because although this video was timely, the comparison is useless because of different shapes.
Although Alu bars have less fatigue strength they are also cheaper so you can change them more regularly. But to decide which one to choose you need to know what kind of forces go through the bar during use. This video has only given us half the information we need.
After buying a carbon seat post at a steal, I'm once again hooked! Looking to replace aluminum bars by control tech with carbon ones. The difference in ride quality is night and day. The new bars were also a steal at $99, honestly I don't care if they break b/c that level of comfort & lightness is totally worth it. Anyone looking to do significant miles on a bike should be looking at carbon components.
@John And you don't understand how handlebars work.
The time it break may not in as you expected, as you controlled scenario. It just create accident
Normal vs osymetric gears
Are you talking about metric gears from Australia, mate?
Oh yeah especially since they just showcased Emma Pooley's bike with non-round chainrings.
Maybe asymmetric chainrings in general ?
Some scientific studies have been done on non-round rings and so far it wasn't scientifically proven with statistic significance that they are better, or indeed worse. Granted these studies have flaws like small size samples and limited experiment time. So for now it comes down to feeling good or not with them.
Chris Froome's osymetric chainrings doesn'tt need scientific proove - he says they give him advantage and he is wondering why other doesn;t use them :D I use in my road bike aka Froome laser cut three oval chainrings 34/52/62 in MTB aluminium bike s17.postimg.org/z96xdahpr/Aero_Bike_EU_front_gears_62_T_20170826_122321_for_forum_with_cop.jpg and I feel huge difference in fighting sweet spot when compared to classic round chainrings no matter flat or while climbing ;) While climbing at lower RPM i used to slide in sweetspot back by pulling SPD blocks and use its smaller diameter to easier increase average RPM, while in the case of classic chainrings one had to change gears to be able keep going up hill. I believe in Chris secret is how he managed to use their osymetric chain rings, and nobody will know what he exactly does since he shows only average cadence and detailed timing within one full 360 deg chainring rotation is not published as I know - Ibelieve in only after race video analysis could reveal such details by frame to frame anlysis of Froome rotation timing - probbaly it is constant rotation speed within rotation at high cadence, but at lower while standing on bike it might be different, I guess.
I think the impact test should use the handlebars with the same shape.
They are both stronger than skin and bones.
uh bone is currently the strongest known material in the world
Yeah ? Then why does your bone break but your bike won't ?
andy But what if I want my bike 🅱️ONELESS?
andy iam pretty sure that is some BS
andy Yeah? Why do we make planes out of carbon instead of bones then?
I broke my back in a bike accident a few years ago and can't ride crouched down any more. Could I put BMX bars or similar on my ancient Kettler frame to help (I'm also 6ft6) and how would they affect the riding? I currently suffer badly after the 20-30 miles I ride a day, and have two centuries in 2 days next April, then a 2 day break until another pair of centuries, so I won't be able to lean for most of it, but speed isn't too much of an issue.
I will add a huge thanks to GCN for relighting my passion for cycling too - now I go everywhere with my son in the trailer, rather than taking the bus locally, so thanks!
You can design either material to any strength you like given there is no weight limit specified and that doesn't matter whats over. I'm more worried about the failure modes. Metal cracks are usually obvious and visible on the surface be it coming from impact or fatigue; carbon on the other hand leaves doubt lingering in my mind even if it looks fine on the surface after an impact. For that reason I stuck with alloy.
exactly!
Carbon vs aluminum wheels
Carbon is stronger. See reserve Carbon wheels of santa cruz.
Wheels are so expensive 🥵
I prefer aluminum. Some of them are lighter than carbon.
Really cool test, you should make more testing videos like this!=)
its probably good to point out that aluminum is prone to failure due to corrosion brought on over time from sweat. if one has a high sweat rate and isn't changing bar tape often then there can be a catostrphic failure. i had a friend go down and break 5 ribs during a crit due to his bars failing. He is kind of a heavier rider.
Crashing with an aluminium bar:"Oh it seems fine, lets ride home." A few miles down the road :" Oh Oh ." Aluminium breaks without warning, happened to me twice, switched to steel on my MTB and to Carbon.
"We turned the machine off" LMFAO!
Much more interesting would be the impact of the weather, rain, low/high temperatures.
When I was racing MTB in Alaska, I got sick of dealing with aluminum bars breaking and switched to titanium bars. Titanium rules!
Accident impacts never occur in the direction that the force was applied in this test. It generally happens sideways, which is the weakest part of a handlebar because forces while riding are never applied that way.
ISO 4210 .... the Real stress test..!! I love the FSA carbon wings
what a video! 6 minutes of research and then this conclution to end with :D
Kosio Varbenov Fk up need to watch test what's this Google it's youtube get a life
Typically, a hardcore rider would crash many times far before either the aluminium and carbon bar fail from fatigue. And speaking from my local racing experience, there's like a 50% chance of a carbon bar cracking upon impact in a crit... And man, that happens almost every week to some poor chap. Also, saying you could ride the crack that formed from the 60cm impact out is plain irresponsible. The next time you hit a pot hole you are going to hit all your teeth out.
許嘉宇 I think the point he's making is that it doesn't snap in half, so you can ride out of the pothole and not crash- definitely not meaning "keep riding it" !!
Haha, he meant just riding back home instead of pushing the bike.
What the hell kind of crit are you doing where there are that many broken handlebars? I race and have seen only a couple of times seen cracked or dented handlebars
I know he meant you can ride home. But I am saying that is a very dangerous thing to do when you have 2 big ass crack on your handlebar. Any responsible manufactur would tell you to stop riding immediately and take a bus home or something. Racers in my area are rich so most of them run carbon bars. It really doesn't take much to crack an ENVE, 3T or ZIPP. Sometimes a slide out when cornering will do. Dropping your bike when you stopped for coffee will also do...
I've people snap the steerer tube off at the stem in circuit racing so I believe him.
I'd stick with aluminium for the insanely lower price, specially in my country where road bikes are super expensive and I still couldn't buy an entrance level one. That love for Road Cycling will never let me have money to spare.
That testing machines can make other things💯
The crash test missed a very important factor for aluminium -- it fatigues at very low stress levels and the micro-damage from that fatigue is cumulative. This means that the alloy handlebar that withstood 80 cm of impact when new, may be damaged at a significantly lower level after it's been in use a while. This cumulative fatigue characteristic of aluminium alloys is one of the reasons why engineers must build in much greater safety margins into their alloy designs. By comparison, steel, titanium and composite carbon do not have the same cumulative fatigue problem. To factor the effect of cumulative stress into your drop test, you would want to conduct the drop test on handlebars that have first been pre-stressed with the fatigue test.
Another factor that was overlooked in these tests was the kind of reinforcement provided in the composite carbon handlebar. The one tested did not appear to be reinforced for aerobar use. I use aerobars and my composite handlebars are all reinforced for them. This means the handlebar manufacturer increases the width of the center portion of the handlebar that can safely accept a clamping force. This is done so aerobar brackets can be added on either side of the stem. These type of composite handlebars might not fail as early as yours did in the crash test. It would be interesting to see what drop height they could handle.
What about a carbon handlebar that weighs the same as the aluminum one? There wouldn't be any weight savings, sure but would it handle the impact tests even better than the aluminum one?
Carbon both flat bar and drops. Have being riding carbon flat bar on my commute/utility tourer for 8 years, a lightweight 120g job made by Bottechia, I've been rear ended in a hit and run, a spill when a numpty kid ran into me in the middle of the road and a spill on iced over compacted snow down the hill to the supermarket (my fault going too fast). Not a murmour, nor to the carbon forks nor the carbon stays, oh yeah,I'm 102kg on a good day and I carry 20kg+ loads reasonably often and I'm not gentle with the bike. (Spesh globe pro). Just bought some 'PRO' flat bars to go on my adventure/gravel rig, I use Modolo Curviussima on my CF racer.
I'm still running TIME carbon composite forks from 1991. Make your own mind up but CF bars all the time for me, I'd never go back to alu, too stiff and not as robust.
You can also check vid by Santa cruz about braking GF and aluminum rear triangle. Guess which one did better in that test.
Honestly if you want carbon it has to be of good quality. I tried changing to a very light carbon from China. It broke after a wheelie.
I stay with aluminum because it stands a higher chance of surviving a crash. Assuming the rest of the bike is fine, I can finish a ride with a bent bar, but likely not with a totally broken one.
Aluminium bars wont bent that much, they break and when they break it happens fast and violently. So you have two options with an AL-bar: it doesnt break or it breaks so hard that you will hit the ground for shure. Happend to me twice.
With an carbon bar, it doesnt break that violently, it is like wood, it will buckle and get flexible but in most cases the bar will remain in one piece and you wont crash into the ground.
I will stay with carbon as it is the safest option.
I had those control tech bar ends! back in the 90s
Aluminium has a fatigue life, carbon should last forever if each stressing is below its tensile strength. If built well.
If the carbon composite structure is so much lighter why don't do the manufacturers increase the wall thickness to match the weight of the aluminium counterpart? It could be much more stronger and the inner diameter doesn't look that much important other than at the very end of the tube (where end plugs can be used).
probably bc the carbonfiber still break if the force is aplied the wrong way so there is little to no point in making them stronger to forces in one dirrection also the prise would go up be a lot
The carbon composite handlebar is already way stronger than it needs to be. The impact test they performed was way more punishing to the handlebar than any vertical impact it would ever experience on a ride, due to the lack of cushion one would otherwise get from their front tyres.
That being said, I think they could've optimized the profile of the horizontal sections a bit better. The handlebars are basically cantilever beams. You want the handlebar to be as uniformly stressed as possible for maximal performance/weight. A triangular width taper with no depth tapering is the strongest cantilever beam gram-for-gram, and this would be easy to achieve with carbon composites. Also, the thinner the walls are relative to the depth of the cross section, the closer the inside edge and outside edge are in bending stress. So you can go with a deeper wing section and use thinner walls to get the same strength with less material, at the expense of increased frontal area and drag. All engineering is a compromise, and the exact solution the engineers decide on depends on the intended application. For example, a time trial handlebar should be ultra slender in profile at the expense of extra dead weight, while a hill climb handlebar should be ultra deep and thin-walled to save every gram possible without compromising rigidity.
I see a lot of comments about steel bars here but how's about titanium people seemed to have forgotten ti bars If done properly as light or lighter than an alu alloy bar but with better damping and fatigue life than steel, I live by the coast so the fact it doesn't corrode either is a big bonus too.
love my controltech ct crossbow on my flatbar bike.
RCFP is also a brittle material. Aluminum is ductile, in addition to the mentioned work hardening.
Hardening makes it more prone to breaking, dork. Quit using words that describe processes that you don't understand.
I had a wicked 40kmh crash shortly after I got my current race bike, I slid on top the bike into a curb, aluminum bars bent a little bit, I just cranked them back and they're still good 3 years later, I have serious doubts carbon bars would have survived that...it's one thing to test impact where the bar can spring around like that with a weight on the end, it's another to hit an immovable object at 40kmh with a 90kg rider on top of it...
Did the aluminum handlebar change shape during the crash test? So it might have not broke but did it deform?
Sure looked that way to me
Yes, because Aluminum is a ductile material, however, in these tests failure isn't considered minor yielding. Granted, I'd consider the change in shape to be small enough to keep riding, but if you've had that much impact, the handlebars won't be what I'm concerned about.
Yes it did bend but you can ride with bent bars while you can’t ride with a cracked bar
You can still ride back 😂
well a bent bar is anoying but yea the pot hole woulf probably fck some other part up harder
What about combination of fatigue and stress testing? How much does lifespan of both carbon and aluminium decreases after for example hitting a pothole?
It’s not impact stress that makes aluminum stronger it’s the fact that it can take more weight and that it will give and bend the carbon just snaps the aluminum will just bend.
do the seatpost test next time please
In terms of years of regular use by a rider who rides, say, 10-20 miles per day, how do these measures translate? Is a year if riding like 100,000 stress tests?
This episode should have shown Si growing a beard and long hair while waiting and eventually looking like Chuck Noland in Castaway. 🧔
I'm a big guy (6'4", 260 lbs). I rode DH for a decade, before coming back to more AM riding. I'm running a set of Oxive carbon fiber wheels.
I am amazed at how strong they are. The wheelset weighs just over 1600 grams, and they are STRONG. I had a crash this summer, moving at around 15 MPH, where I stuffed the front wheel sideways into the ground, full on 90 degrees like.
I took a beating. My bike took a beating (I twisted my stem 90 degrees on the steerer tube, the brake calipers on both ends of the bike had to be realigned, and my rear thru axle got twisted weird in the frame somehow).
My wheels were perfect. Not a mm out of true. As a big guy, I have a history of destroying rims. My carbon rims with a season of riding have a few nicks and scratches, otherwise they are perfect.
Time is not a friend to carbon; the resins can/will age (dry out - especially with temp changes & humidity fluctuations, again over time), which would dramatically change it's results for both tests. Also, the impact to worry about with carbon is not so much the load spread over the length of the bar, but an impact on a specific spot on the handlebar. Say a one inch tube striking the top bar just outside where it attaches to the stem (as what might happen in a peloton crash) - there also the carbon will have a significantly less impact resistance.
They are sweet, but not worth the minor weight penalty for me (or even most of the pros who don't even have to pay the extra out of their own pocket)
have you heard of corrosion? i ride all types of bikes, i trust the carbon in all of them.
@@tribalismstudio that's why you wash your bike every now and then
So in the breaking-test you compare an aero-handlebar with a normal round handlebar?
You would better compare apples with apples and pears with pears.
What about compairison of stiffness or comfort.
I'm currently deciding between two handlebars for my gravel-project. Alu: 233g / 80 Euro. Carbon 190g / 260 Euro.
OK, 40 gramm ist 40 gramm, and if you don't know where to safe them, you perhaps need this carbon handlebar.
But if you go out for a ride these 40 gramm won't bother you.
So for me would be verry interresting, what about stiffness and comfort - maybe also which ist stronger - but only for the same shape and dimension of handlebar.
I don't think the argument is really understood here. Everybody knows carbon fiber is stronger as it's engineered to be, but only in an "as intended" to be used circumstance. You rightly pointed out that the aluminum would be stronger in a crash, and THAT is why people choose aluminum (well, that and the price tag). Coming from the world of mountain biking I've seen tons of carbon parts having to be trashed because of damage from crashes where an aluminum part would've fared just fine. Case in point is my aluminum Santa Cruz Nomad. The things I've done to that frame.... yet I've not had to replace it because I've scratched it.
What about the issue of damage visibility? Isn't it more of an issue with carbon having invisible damage where as alloy it's more obvious to the naked eye?
Daniel. Yes, the problem that isn't mentioned is that visible damage could well be hidden under bar tape (happened to me).
Dude or rather GCN folks the problem is with the counterfeiting of carbon handle bars being sold online or even at your friendly neighborhood bike store for cheap that use bike people just cannot over look e.g.: $50 versus $350 for a handle bar.. Besides the problem with pro peloton usage is that the mechanics cannot see the cracks within the carbon you easily saw in your test after a crash. Anyways the general rule is to replace the carbon bar after an accident and replace the carbon bar after say 2 years of use. My Aluminum bike down tube finally cracked and then slowly grew longer after 13 years of use until I could tell there was a problem e.g.: the chain shifting up or down a cog on hard accelerations because the frame flexed. I really do understand how a Pro cyclist can ride a bike and tell when the frame characteristics have changed. When carbon frames go out of speck why they just catastrophically fail it is my understand. Recently my carbon fork made a crack sound while traveling down hill say 20mph after hitting a pothole. After visual inspection I could see nothing wrong..no cracks. But it is my understanding that inside the fork voids or wrinkles of the carbon fibers can buckle and peel away weakening the fork blade.
5.8 Kilograms = 12.7868112 Pounds *2 = 24 pounds...tire and wheel and fork deflection will allow this # to reflect the actual weight of the rider that may weigh 280 pounds.
36 Centimeters = 14.1732283 Inches
48 Centimeters = 18.8976378 Inches
60 Centimeters = 23.6220472 Inches
72 Centimeters = 28.3464567 Inches
84 Centimeters = 33.0708661 Inches
Forgive my ignorance, but what about stainless steel bars? I imagine it depends on the composition of the steel but is there any argument to be made for steel?
Could you do a test on what happens if you have aero bars or other stuff mounted on the bars? Would the carbon simply snap where it's clamped?
I think that happened to a rider from Ag2r recently when his TT bars broke.
If "the other stuff" means the brake levers, I am interested in as well.
The alloy bar on the impact test got the drops straightened out :)
What about on gravel bikes? Do they make handlebars stronger for them? Seeing as they see more stress over time?
changing the bar's clamping area diameter over the years has made that area stronger, yes.
This is all well and good for roadies, and I’ll probably go carbon bars when I build mine up, but for mountain biking aluminum all the way.
Solid choice!
In a crash, its much harder to determine the extent of the damage to carbon bars vs. alu. I typically continue to ride the same bars post crashes so for that unknown multiple crash factor... I ride alu for road and mtn.
In the stress test, is the stem standardized? Because the way the (stress) machine works, alternately pushing down on the ends of the bar, how much of that the bar could take is, in part, dependent upon how much flex is in the stem. The more rigid the stem, the more stress is put on the bar (because a flexing stem absorbs some of the energy, while a stiffer stem absorbs less, allowing the bars to take the energy). It would be better to mount the bar directly to a rigid upright, so the maximum amount of force from the machine goes into the bar. Maybe also push down on both ends of the bar at the same time, to maximally stress the bar, rather than inducing torsion into the mount, thereby eliminating a variable.
What information actually matters and how much? Most bikers are not pros much less racers. For realistic stress from usage, and durability should one choose everything aluminium?
Do we ever get to customize all components in bikes under £1500? They come packaged as one product minus pedals unless one wants to replace and upgrade.
Any suggestions?
I can say yes. AL can be resistant to virtually any force vector (won't say absolutely any force vector, to play it safe), but for carbon, only in its intended ones.
I will always go with Aluminium because I want crash strength. I've bent 6 seatposts on a mountain bike and quite a few handle bars in my day and I would much rather have it bend than shatter. Thanks.
Carbon doesn't just snap off if installed properly; infact, if you're rough on your stuff, move to carbon, you'll be way better off.
i like your video production. do it your own style dont get bought by big tv networks.
Si sounds like a material engineer!
So why is it that both of my local bike shops that have been around for a very long time, (when steel was the frame of choice) that these shops are seeing far more failures due to fatigue with carbon fiber bars then they ever saw with aluminum bars? They also are seeing more CF bars being broken in accidents as well, but that was pointed out with this video.
Now there is some debate as to what is causing CF bars to fail, the mechanics were also saying that there may be some problems that look like fatigue failures when in fact they were operator installed error that over torqued the bars and the stem clamps crushed the fiber just a bit and over time they broke. There's even controversy that some mechanics either don't know the exact torque setting to use or the company with the bars gave wrong torque information. Something that never was even remotely considered being a problem with AL bars.
The mechanics I spoke to about this all said they would never use CF bars, and one went as far to say he would never buy a CF bike because they're seeing a higher failure rate of CF frame as well vs other material they currently sell or use to sell, but that's another debate. To be fair there was one mechanic who does some state racing, his race bike is all CF including the bar, but when he's not racing he uses another bike for training that has AL bars, but that as he said comes down to weight and on the racing bike he's cutting weight as much as he can.
The impact test is nor fear because the handle bar shape is not the same. The place where the carbon one cracked was flat for aerodynamic reasons compared to a cylindrical one on the aluminium one.
It also depends on the stem aswell. Mixing aluminium components wih carbon can reduce the lifespan of the part especially in winter . This is because the salt reacts with both materials and makes a battery which corrodes the carbon.
excellent vid chaps
Did you test Titanium bars? If not would be interesting and they are available at least in straight and riser for MTB. Do a search of Carbon fiber handlebar breaking to see plenty of videos of breaking handlebars. Have seen in professional road racing and drop bars as well.
I once was In a heavy side on collision with a van. Almost everything In the bike was destroyed. But the alu syntace bar did not break.
Alloy bars certainly are tough!
Or if you're really worried about fatigue life you can use steel or titanium, which have an endurance limit below which no fatigue whatsoever occurs.
Another great video
+NY Brit thanks!
So, why did you use a round aluminum bar and an aero with internal cable route carbon bar for the impact test? Possible results were stacked in the aluminum favor by the shape of the bar. For the comparison test to be reliable the bars would need to be the same shape.
don't have any carbon on my MTB anymore. Two seatposts snapped. Both with no external sign of wear. And no , I'm not a fat bastard.\just used the bike as it was designed.
If I build an MTB (I plan to build a trail bike once I dive into MTB riding), it'll be carbon-free too. After all, it's supposed to be a fun bike, not a bling bike.
The weight difference on those bars is 55 grams, yielding weight savings at probably >4 dollars per gram. The aero bar showed earlier is much more than 169 grams.