I hate carbon

[volts]

Haha, well, absolutely! But.... I've really been looking for a man logic reason to get one.

I can just say why I got one.
1) I wanted that particular bike, and no alu option was available.

Some reasons I have heard:
1) Carbon is lighter/stronger
2) Manufacturers claim they can make more intricate frames with carbon
3) Different feel (some say it has dampening properties others say it's snappier, I have no idea really)
4) More bling to show your dentist friends
5) Easier to repair than alu

 

[A06]

I have to say, having read all of this thread, I still can't see why I should go for a carbon bike!

I currently own 3 bikes, a Kona Shonky Chromo DJ bike, A carbon RM Slayer and an Alloy RM Altitude PP. You are in Scotland...think of it like golf clubs, different materials for different uses.

I prefer Chromoly for hardtails as they do feel a bit less harsh (more supple is often used to describe). Comparing my two RM's frankly it was a matter of price over preference. Got my 2020 Slayer as new old stock at a considerable discount as the 23's were arriving and the PP Alloy was the absolute cheapest configuration available knowing I was going to put all of my Gucchi bits on it from my Slayer and parts bin.

Only compelling reason to go Carbon over Alloy on an eMTB where weight dosnt matter would be your preferance of how they feel. They both feel distinctly different.

 

[Fangs2k]

I think the main problem with carbon is how they will end up as landfill when they done for. It's not smart.

As an aside, I’ve disposed of dozens of carbon composite aircraft/airframes over the last decade, a lot of them went through an industrial carbon ‘chipper’ (like your garden shredder) and were mixed with road surface material to create a hard wearing, high grip and lower noise road surface.

A few other bits ended up as executive desks etc! I can’t see that being the case with a carbon Levo though…

Everything has a footprint, the only ‘green bike’ is no bike at all.

 

[FirstAscent]

But do you accept that cracking and breakages do occur, or do you just think you've been really lucky and have received an unbreakable carbon frame.

I've ridden White bros forks for a long time, and had no problems, i even got them 2nd hand. But the truth of the matter is its not really the material designed for the most part for long term use ,in an environment where its going to suffer damage as part and parcel of the sport(or hobby, because thats really what it is)

Were it cheaper, then that would make it more acceptable for use in that it can be replaced without breaking the bank.

It is important to note that many bike manufacturers will have lifetime or long warranties on their frames, but only if they are made of steel or alloy and carbon is excluded. I think Kona for one has long held this clause in their warranties.

Im quite happy that if i drop my (alloy) bike and scrape, scratch or even dent the frame its going to be fine. Im not sure i could retain confidence due to the nature of the sudden catastrophic failure that carbon is known for. Especially if its involving speed, rocks and the like

oh most definitely I can accept that. Carbon isn't indestructible. Although I wouldn't say I've been lucky either because I've had some good crashes on multiple manufacturers carbon frames.
All the carbon frames I've been on were:
9ZERO7 Carbon Whiteout (fat bike)
2012 Trek Session 9.9
2019 Trek Session 9.9
Transition Carbon Covert
Evil Wreckoning
Specialized Turbo Levo

The Evil, Transition, and both Trek DH bikes have all had some proper crashes with zero issues. sure some scratches but they're still going strong! I currently own all these bikes listed above still too and they are still ridden.

But yes to your point, I'd say these are respectable companies, and without a doubt there is lower quality carbon frames out on the market. and who knows how they were all made. I agree that JUST because something is carbon doesn't make it amazing. but done right, yes it's epic! haha

I always tell people, if you can afford it, go for it. and if not, get an Alu frame and enjoy an epic time still. Personally, given the choice, I'll never own an Alu frame again. The only Alu frame I bought fairy recently was a Trek Ticket S, and that was ONLY because they don't make a carbon model haha.

 

[JP-NZ]

Im quite happy that if i drop my (alloy) bike and scrape, scratch or even dent the frame its going to be fine. Im not sure i could retain confidence due to the nature of the sudden catastrophic failure that carbon is known for. Especially if its involving speed, rocks and the like

I had a Kona FS enduro bike and it got a thumbprint sized dent about 2mm deep in the downtube. About 6 months later after some small jump lines it deformed the downtube and bent in the same spot. Frame was trash after and Kona wouldn't warranty due to "impact damage".

Carbon won't dent or deform like alloy tubing does. End of story. There is a reason majority of top end EMTB, Downhill bikes and Enduro bikes are all Carbon.

 

[A06]

This must be one of those topics that gets tossed out every so often when folks just want to churn up debate lol.

The OP's original statement painted carbon and being ill suited for use in MTB frames. I think that has been solidly debunked as a general statement. Materials Application Engineering is a thing and a career path and the big companies employ such people or at least go to a 3rd party for consultation.

If it makes sense or has any appeal on an individual level...well that's an individual decision.

Aluminum frames can and do fail just as the same can be true of Carbon. Minor carbon damage is easy to repair at home while aluminum requires a bit more equipment and skill to do it correctly.

Two additional considerations to the conversation would be how many "dented" aluminum frames are ridden when they shouldn't be because the damage isnt readily visible (such as my cracked weld). And secondly since the cost of aluminum is considerably less is it fair to assume most entry level riders are on aluminum and not pushing the bikes as hard as a more experienced rider on a carbon bike would? If Arron Gwin rode bikes of both materials equally which would fail first? If a world class rider took a nasty crash would either material be safe to ride without detailed inspection?

I think one thing that carbon does provide is a more definitive diagnosis of failure. Yep its smashed and not safe as evident of the crushed member. Vs aluminum where I bet most would say oh look its got a dent but its fine to ride...until the hairline fracture in the weld fails upon landing the following ride.

Personally I'd like to see a nice chomoly emtb since weight really dosnt matter with a motor. If there were a chromo 190-200mm coil shocked emtb...hell yeah Id buy one.

If I'm picking sides then my position is C neither of those materials is my preferred choice and I'm writing in ChoMo as a 3rd option as its superior to either as a material (weight not a factor) for emtb

 

[FirstAscent]

And secondly since the cost of aluminum is considerably less is it fair to assume most entry level riders are on aluminum and not pushing the bikes as hard as a more experienced rider on a carbon bike would?

there are probably more experience riders on aluminum frames in my opinion, just from what I've seen in the wild haha.
I have a lot of carbon frames all custom built by me fully spec'd out and I constantly come across absolute shredders that are WAAAY better than I on some pretty beat up bikes.

I'll be the first to admit I'm not the best out there. I love me some steep techy lines but I suck at jumping for example. I always come across people at local trails or bike parks that are VERY talented on "inexpensive" (comparatively) bikes.

But then of course, yes I do think more entry level riders would be on aluminum frames as well simply for the lower cost of ownership, especially if they are unsure how much they'll like it.

 

[Humanbeersponge]

The options for recycling of composites is growing rapidly with a number of processes available to do this but there are always negatives. Using pyrolosis uses a lot of energy and the reclaimed fibres generally have a reduction in their properties than the virgin materials. Another issue is that currently there is not a big enough market to create a circular economy. Very few people are using recycled carbon.

The real benefit is manufacturing composites with the recycling already incorporated into the manufacturing. Using resins that can be simply submerged into a solution and this breaks down the resin from the fibres. I witnessed this while at JEC the world biggest composites show in Paris and its what is being looked at for things like wind turbines.

With long term performance Carbon works very well with fatigue as long as you don`t go beyond acceptable limits on bending and shear. Impact can be an issue but that`s the same with all materials. Horses for courses, go with what you feel suits.

 

[A06]

there are probably more experience riders on aluminum frames in my opinion, just from what I've seen in the wild haha.
I have a lot of carbon frames all custom built by me fully spec'd out and I constantly come across absolute shredders that are WAAAY better than I on some pretty beat up bikes.

I'll be the first to admit I'm not the best out there. I love me some steep techy lines but I suck at jumping for example. I always come across people at local trails or bike parks that are VERY talented on "inexpensive" (comparatively) bikes.

But then of course, yes I do think more entry level riders would be on aluminum frames as well simply for the lower cost of ownership, especially if they are unsure how much they'll like it.

Seeing you are in Portland I must disregard your observation of the number of shredders on Aluminum bikes. After living in the PNW for 30 years Portland's DNA is to be retro for the sake of being retro. If one more hipster tries to convince me that scratchy LP's sound better than digitally remastered files I'm going to loose it. LOL just playing with ya!

 

[steve_sordy]

I have to say, having read all of this thread, I still can't see why I should go for a carbon bike!

When I was riding mtb I bought a bike because I liked the test ride and it turned out to be CF frame. I was a bit hesitant with it on the work stand to start with but very soon got used to it. The next mtb I bought was CF by choice. My first emtb was CF by choice because by that time I was having lower back problems and arthritic knees, so a lighter overall bike was important to me. (Lifting on/off the bike rack, over locked gates and styles etc). By now a CF-framed bike is normal and I have no fears about them breaking under use. My 2nd and current emtb also has CF-frame.

I have never had the opportunity to ride the alloy and CF versions of the same bike back-to-back, so I can't be certain that the ride is different, for better or worse. I just know that I love the CF-framed bikes I have had and that they are lighter.

 

[Waynemarlow]

and that they are lighter.

I'm not sure that is the case anymore. With the hydro formed Ali frames the Ali weight is getting pretty comparible mainly due to the CF being over built to withstand user damage ( you would be amazed with proper finite element analysis how much thinner you could get the wall thickness if you didn't have to account for user damage ). I think on the early Trek Rails, the CF frame was actually heavier.

 

[FirstAscent]

Seeing you are in Portland I must disregard your observation of the number of shredders on Aluminum bikes. After living in the PNW for 30 years Portland's DNA is to be retro for the sake of being retro. If one more hipster tries to convince me that scratchy LP's sound better than digitally remastered files I'm going to loose it. LOL just playing with ya!

haha, ah man, thanks for the laugh today. Well if it makes you feel any better, at the time of writing I was in SoCal and have been for the past 6 weeks. Heading back home next week I think though

I'm not sure that is the case anymore. With the hydro formed Ali frames the Ali weight is getting pretty comparible mainly due to the CF being over built to withstand user damage ( you would be amazed with proper finite element analysis how much thinner you could get the wall thickness if you didn't have to account for user damage ). I think on the early Trek Rails, the CF frame was actually heavier.

true, although I think, in general carbon is still typically lighter when compared to it's Aluminum counterpart.

but yeah all depends on how the companies design it. they can just as easily beef up the CF construction even more to where the weight is similar to the aluminum version. proper engineering can really reduce the weight without reducing strength for sure.

 

[steve_sordy]

I'm not sure that is the case anymore. With the hydro formed Ali frames the Ali weight is getting pretty comparible mainly due to the CF being over built to withstand user damage ( you would be amazed with proper finite element analysis how much thinner you could get the wall thickness if you didn't have to account for user damage ). I think on the early Trek Rails, the CF frame was actually heavier.

I was buying alloy frames that claimed to be "hydro formed" many years ago. I didn't disbelieve the claims, I only had to look at the changes in cross sections approaching joints to see for myself.
Every CF-frame that I have bought was as far as I could establish, lighter than the alloy version.
I can't speak for the latest advances in alloy forming as I have not bought an alloy framed bike for almost exactly ten years, when I bought a Norco Sight 1, in late Mar'13.

The thinnest and lightest frame I ever bought was in 2010 when I bought a Kona Dawg Deluxe. The aluminium alloy of the frame was dosed with Scandium. In very small quantities (about 1% give or take), Scandium increases the tensile strength of aluminium by 50%. Tensile strength is not the same as stiffness of course, so the frame weight reduction was 15%. The frame was not as light as a CF-frame would have been, but almost! Kona claimed that Scandium alloy frames had all the "benefits" of alloy and none of the "disbenefits" of CF. It was this Scandium alloy of aluminium that persuaded Kona that carbon fibre frames were not for them. But fashion and consumer likes/dislikes are not necessarily motivated by fact, so Kona suffered in competition with other bike makers that had CF frames to offer. Their late entry to the CF marketplace may be why they lack confidence today in offering warranties as long as their competitors.

 

[Mteam]

I've had carbon and alu frames ,but I've never tried the same model of bike in both carbon and alu in order to see if I could feel any difference. For me it's mostly about the weight saving, but a carbon frame does also look nicer, with no welds. Even the alu frames where the welds are smoothed don't look as good as their carbon equivalents.

It's personal preference ,a carbon frame is typical lighter than an Alu frame for the same model of bike, but is more expensive,if you don't consider the carbon frame to be worth the price premium over the alu then don't buy it. Of course some bikes are not available in alu (or carbon) so if you want that bike you have no choice.

Since I started mountain biking in 2007, I've owned 2 Alu frames , and 4 carbon frames , I've had 1 alu frame failure and 1 carbon frame failure. Both failures were covered by the warranty. But that's a 50% failure rate for alu and a 25% failure rate for carbon (yeah I know my anecdote means nothing)

I'm happy to ride a carbon frame.

One area where I won't buy carbon is rims, their cost is not worth the weight saving and their ride feel has not been great, and they have all failed. So it's alu rims for me.

 

[chamaruco]

Anyway,….LPs sound better than CDs…

 

[Just gan]

Never really looked upon it as a material you should be building an MTB out of

Sure I've heard the argument that F1 superduper racing machines use it, but those guys have millions to spend, and can replace any part even after a single race.

Bikes get scraped, and i feel that lets moisture inot the layers. Plus its not so strong it doesnt crack or break or anything like that and when it does(or if rather) then the replacement cost is rather spendy.

I had play in my headset on carbon frame my fault but can't be repaired. So new frame.

 

[Just gan]

I had a Kona FS enduro bike and it got a thumbprint sized dent about 2mm deep in the downtube. About 6 months later after some small jump lines it deformed the downtube and bent in the same spot. Frame was trash after and Kona wouldn't warranty due to "impact damage".

Carbon won't dent or deform like alloy tubing does. End of story. There is a reason majority of top end EMTB, Downhill bikes and Enduro bikes are all Carbon.

Yes I broke two decent alloy frames Marin Mount vision and Rocky Mountain Slayer. Not doing anything heroic on them but levo expert has been hammered . But headset worn so replaced after two and a half years.

 

[Guyt]

I have used carbon components extensively for windsurfing. The best masts and booms are 100% carbon and high end boards are either Being

I have used carbon components extensively for windsurfing. The best masts and booms are 100% carbon and high end boards are either all carbon or a mix of carbon and other composite layers like australian pine or bamboo

Without full disclosure of the fabrication process I would not buy a "carbon" framed bike...............and unless I could see how the inevitable , even minor, impact damage was ameliorated in the design I would not consider carbon a suitable material for MTB/EMTB frame construction. For road bikes where stiffness and weight are primary consideration, and impact damage far less likely, I see the rationale..........but would still want to know what I am being asked to pay for!!

I completely agree with on the use of carbon in windsurfing equipment. I am a windsurfer too and have 100% carbon masts, booms and I always buy high end boards with maximum carbon use. Carbon is extremely durable on normal use, but you are right when you say it is prone to punctual damage, for example dropping a carbon layered board on a sharp rock.

I was considering a carbon frame for a future mountain e-bike (a Cube), but you made me re-evalute that choice. I look at my present acoustic MTB and I can see quite a few small dents on the aluminum frame, resulting from epic falls . Would a carbon frame survived after those falls? Not sure.

 

[Gavalar]

Sadly, like most carbon.

The majority of carbon waste from production and trimming out of the mould goes to ocean fill, Mr commencal himself states this as the defining reason he will never produce a carbon frame.

 

[chamaruco]

And the alu frames are ecologically sustainable?

 

[Hardtail]

And the alu frames are ecologically sustainable?

Aluminium is one of the most environmentally sustainable metals. It also has the added bonus of increasing the risk of Alzheimers, so even if it is not the most environmentally sustainable material you wouldn’t remember anyway…
My dirt jump and MX mates prefer Ally over carbon.

 

[Superses]

So, to someone who's never ridden a carbon bike, what are the advantages over alu? Weight, I imagine, but that can't be much of an issue for an Emtb?

I've heard people talk about ride feel, but is there really a difference?

I think a lot of it is bullshit.When people tell me one or the other has more/less vibration absorbtion properties I refer them to their 2.6 inch tyre and its variable pressure as having a far more significant influence n "vibration". By all means have carbon handlebars(I do) but bear in mind that unseen damage may result in catastrophic failure when you least expect it .Aluminium on the other hand will more than likely "fold" before it breaks. Either does not bear thinking about

 

[mtb-steve]

My dad likes Carbon frames, and has used them for years with no problems, he's also repaired them using repair kits and they've gone on to be used for years after the repair. He will not use carbon wheels or bars though, he's broken rims and had to walk home, and personally been there when carbon bars have snapped, he's never had his break though.
I also used to do archery and I've seen carbon arrows break right next to me, she had three go in a row so the rest were thrown away, that just showed how consistent the manufacturing had been, and she must have rotated their use very consistently too

 

[Ark]

It also has the added bonus of increasing the risk of Alzheimers

Nor proven... seems like a myth

 

[Just gan]

I think a lot of it is bullshit.When people tell me one or the other has more/less vibration absorbtion properties I refer them to their 2.6 inch tyre and its variable pressure as having a far more significant influence n "vibration". By all means have carbon handlebars(I do) but bear in mind that unseen damage may result in catastrophic failure when you least expect it .Aluminium on the other hand will more than likely "fold" before it breaks. Either does not bear thinking about

I've never seen any difference on my one but only been mtbing since 86

 

[Streddaz]

Aluminium skinned and ribbed aircraft are scrapped after a max duty cycle of about 1/5 of the equivalent carbon aircraft, I wonder why that is ?

Aluminium has an endurance limit, it fatigues when it is flexed and over time will eventually break. Carbon fibre has an unlimited fatigue life.

 

[Plummet]

In an e-bike the weight difference is approximately 2kg from full alloy to full carbon equivalent.
ie frame, handle bars, wheels and maybe cranks.

I'll be honest, on an e-bike its less of a % difference a full fat e bike. Its still heavy af.

 

[maynard]

My carbon bike hates you

 

[Mikerb]

Honestly there is some real rubbish being commented here!! First of all "carbon" is not an adequate description of a frame manufactured using a composite of carbon mat. It does not for example say that the composite is 100% carbon, neither does it say what modulus or carbon fibre mat type is used. You may as well just say it is plastic!!

Carbon is easy to repair with no special tools!! Really!! The main tools required are experience and skill and any broken section of a frame requires considerable overlap of carbon mat layers meaning the repair will be large and the section repaired will be highly unlikely to reflect the same flex/no flex characterisitics of the original composite, and that can lead to future repeat failure.

Carbon has an unlimited fatigue life!! No. Firstly a composite construction relies upon epoxy resin to bond the layers together. Epoxy resin can suffer from fatigue, indeed the most common reason for carbon composite failure is delamination. A special epoxy is also required for unpainted finish otherwise it suffers from UV damage.

Im not knocking carbon composite. In the right applications and fabricated by composite experts it is a fabulous, albeit delicate construction and one not best suited to a design that requires tubes to be bonded together at different angles and with different stress directions..... and multiple interfaces for bearings etc.........in my opinion!!

The marginal weight difference between most mtb carbon composite frames and hydroformed ally tells me that the designers are really taking no advantage that could be had in terms of light weight or stiffness/flex ( unlike carbon composite road bike frames which clearly do just that), either because they are using low modulus woven carbon mat or because the composite is not just carbon..........or there is too much epoxy......or all of them.

What you are left with is aethetics.........ie a frame with no welds. So if that is worth the £ extra to you then fine.

 

[2WheelsNot4]

"Repair kits"
oh how easy, we've got repair kits.

But lets face it, those are little better that wrapping some tape around and over the area and allowing it , or the epoxy to harden.

Frames are built and use vacuum moulds to form and apply a great deal of pressure to force out any trapped air bubbles. So jsut wrapping a bit of tape around not dissimilar to an elastoplast isnt really,truly doing much. Its strengthening the area to some degree, but if you were to do it properly, you would need to form a vacuum around the 'patch' and lets face it the vast majority dont have access to one of those(Though I do, but im not the lending type )