[Closed] Carbon fibre its rubbish

yup. So, am I mad to get carbon bars for my SS. Probably tougher than me, but I'm a fatty and put a lot of leverage through the bars when straining up hills?

Right application it's great, wrong its not. wouldn't trust it on MTB rims or saddles, but anywhere else can't get enough; never had a part fail on me yet 🙂

Yep - aluminium never fails.
[img] [/img]

No its not crap. Is that good enough?
Oh, you'd better not ever fly in a commercial jet again as on most of the modern ones the bits that stick out of the sides and hold the engines on are made of carbon fibre (unless its on a treadmill when its actually the wheels that make it fly).

Lost confidence in my 575 as my friends bikes crumbled around me. For all mountain I've gone back to aly. Even ditched my carbon bars. I never for one moment thought they would fail but they had to go for peace of mind.

not to forget the masses of 575 owners whos seat stays part company with the dropouts at regular intervals

Simply not true. Not even close. Yes, there have been failures, but name a bike that hasn't......

I've broken 3 steel and one titanuim frame, and dented an alloy one.

Does that make them just as bad?

To be fair, carbon is pretty much the only material I've not seen broken in my circle of riding buddies, and there's a fair few of them that I know of.....

PeterPoddy - Member
my circle of riding buddies, and there's a fair few of them that I know of.....

Personally I had the 575 built up for light duties but now and then I'd throw on some 36's and fat tyres and ride some silly stuff and for this I wasn't confident that it would stay in one piece with the back end flexing all over the shop. Also it had very little mud clearance and the abrasion was starting to show on the inside of the stays. A material that you can slice with a Stanley knife, in mind isn't tough enough for throwing down rocks. Torsionally rigid yes but as tough as alloys. No. IMHO of course.

A material that you can slice with a Stanley knife

are you talking about aluminium again? there was a lot of alu can cutting going on in that bivvy thread.

🙄

I've broken 3 steel and one titanuim frame, and dented an alloy one.

Is there a weight issue here?

Love me Yeti ASR C but too much on my mind every time I fall,every time it creaks.
Best bike I have ever ridden tho!

my VF2 is performing superbly, albeit a carbon rear end only.

sublime bike. and suprememly stiff at the rear too...

loving it 🙂

Oh, you'd better not ever fly in a commercial jet again as on most of the modern ones the bits that stick out of the sides and hold the engines on are made of carbon fibre (unless its on a treadmill when its actually the wheels that make it fly).

I'm not going to get directly involved in this debate, as the only carbon bike thing I have ever owned is the seat post on my Trek road bike.

Anyhoo, I once met a bunch of materials engineers on holiday, and they said that they had tested some CF bike frames and components, and their conclusion was that the quality of the CF was seriously poor, compared to aeronautical CF. As a result, none of them would go near CF on a bike.

Just sayin'....

I'm going back to string n glue for my new SS, but I won't use carbon bars on the single speed, I maul them to death and they all get very creaky and flexy after about 6 months abuse.

Quite happy with carbons on the 5" boingy bike though.

As with most things, use the correct material for the right application and there are minimal issues.

also worth bearing in mind that lots of bike bits used to be designed for typical rider weights of around 12st, whereas lots of british riders are seriously lardy boys who still think a 3 lb carbon hardtail will be fine with a 20stone rider 😯

I still have carbon bars and rigid forks on my winter hack 29er. Oops, mentioned 29er! I'm not totally against witchcraft but like me old trail pixie mate Taz says, certain materials for certain jobs init.

Often read posts on here about people breaking all manner of components whether it be carbon fibre, titanium or aluminium.
Do I think these materials are crap. No. I think the riders are crap and need to learn how to ride!

CF quality for bikes may be poor compaired to the Aerospace industry, but then was the last time you saw a bike fly like the Dreamliner?

lardy boys who still think a 3 lb carbon hardtail will be fine with a 20stone rider

Mine is
😈

No... (Carbon) best bike I have ridden and I have ridden quite a few nice ones 🙂 touch wood nothing broken!

I have no issue with CF as long as it cannot be hit by large rocks and leave it impossible for me to see whether/how it is damaged or not.
I would rather not have it on a MTB tbh but would not object to it on a road bike.

Mine is

for now 😉

Do I think these materials are crap. No. I think the riders are crap and need to learn how to ride!

[IMG] [/IMG]

I would rather not have it on a MTB tbh but would not object to it on a road bike.

[img] [/img]

😯

"I would rather not have it on a MTB tbh but would not object to it on a road bike."

There is probably a lot more stress subjected to a road bike frame/forks on thin tyres and no suspension than your average MTB!

Is it only me that remembers exactly the same being said about aluminium, around 15years ago - poor quality, too weak and it'll fail catastrophically, and probably kill you in the process..?

I've got lots of CF on my CF frame and I love it 🙂 . Oh, and I've snapped 2 aluminium frames.....

tazzy that might just be crash damage
coleman I said it was the effect of damge by rock strikes that worried me not how strong it was though I am nit sure you are correct re stress

I know junky, but it's a funny picture 😀

Junkyard. OK. Fair comment.

But, hitting a pot hole at 50 mph downhill on Tarmac puts one hell of a jolt through the fuselage!

Indeed ..there is a website dedciated to failed CF iirc
I dont think it is pants or worse than anything else itis just rock strikes that worry me
[img] [/img]

http://www.bustedcarbon.com/

EDIT: is the bike forum always this civilised and polite 😯

You know you want one....
[IMG] [/IMG]

I had a 2008 yeti 575 which I used for mainly xc trail riding and the carbon swing arm snapped ! my mate would follow me and see my rear end flex so much it was scary ! I stick to alloy now as I have had a bad experience with carbon 🙁

Yep - aluminium never fails

Though i think the picture you show is down to an installation/design fail rather than material choice?

Pastcaring - no not trolling you Muppet! Stupid? well the jury's still out on that one.
However, in over 25 years of riding offroad and road, I've not yet managed to break any major components whether they be carbon, titanium or aluminium! Although I have managed to break various bit of myself in the process! So feel suitably qualified to have an opinion.

[img] [/img]
Folding bike?

There's carbon and there's carbon. You can squeeze the rear end of a Yeti ASR5 without any bother (I've tried), but give it a go on a Santa Cruz Blur. Absolutely solid. There's a reason good stuff costs a bit more.

Oh well. I'll be riding the 3 Peaks on a 1200g full carbon frame. ** shrugs **

I have always stayed away from the plastic bikes but rode with a chap the other day who had built up one of the new On One 456 Carbon frames. Nice bike....he gave it a good hammering and it was very impressive-none of that usual hollow sounding noises from the frame but still really light but compliant. Still not sure as to logevity for people of my weight so I am going to hang on to see how they perform in the long term before I invest.
I must say that the bike that I have seen most broken is from Gary Fisher brand where the carbon rear swingarms have snapped.

Someone once said theres no such thing as a bad material just a bad application for it

On the other hand it does mystify me why people would deem that aerospace Quality defines a good product

Those Chinese bikes everyone seems to be cranking out for a third the price of a uk made frame surely can't be that bad can they.....would people pay more for a product 3 times times the price for a uk made and designed frame.

sorry Coleman, been waiting to use that for ages 😆

Indeed ..there is a website dedciated to failed CF iirc

never trust a website that spells fibre "fiber" ffs - it's all photoshop!

Phyba.

I have absolutely nothing useful or constructive to say.

I agree with the OP, carbon is bollocks.

which are these UK made bikes you speak of?

How bigger role will CEN testing now have? regardless of material?

It was more a question would you pay 3 times the price for a frame

IMO the CEN testing is a moot point when it comes to carbon frames

CNT is supposed to negate the weave issue"/lay/pattern weakness in cf?

On One 456 carbon, smashed it down rock gardens at Laggan Wolftracks even done the world cup downhill course at at Fort William in 8 mins on it had loads of crashes on it done large drop offs and jumps and its still in one peice, probably done more than most people would do on a bike like this and its perfect, got my 36 RC2 Fit forks on it big 2.5 tyres and it suits me great
The frame passes all the toughest CEN tests so im more than happy with carbon, i know they are hand rolled so one may pass the CEN tests but obviously they are all slightly diffrent in tests.

by a 1860's beam engine(ellsworth).Thats my rant over for today,feel better now

I remember Truth frames saying you had to use an inline post, the seat tube wasn't strong enough for a layback one. Great.

Carbon all the way. If you don't want to buy one, don't, no one's forcing you!

Done a lot of stuff with carbon fibre on rallycars etc. It is incredibly strong for its weight and torsionally stiff. Its the intended application that always seems to be the problem. Unless the frame or component has a lot of protection say from a outer coating of resin etc they do seem to be compromised by a point loading causing a chip or crack. A friend of mine bought a Trek EX9 carbon hardtail and they left off the plate that protects the BB area from chain rub. When he commented that the BB area had a few scratches on the fibre off the chain they said it would be a good idea if he saved up and bought a new frame just in case. This was a 2.5K bike FFS! The bike had only just had its first service. I know, you would have thought that they would have set up the derailler so the chain stayed on the granny gear. As for getting a CF bike I could only justify one if I lost a shed load of weight. Steel is real for me at the moment.

With carbon, pick your manufacturer carefully. There are only a handful of carbon bike brands worth riding, were they are made properly, Time, Parlee and Calfee. There are a couple of others but cannot remember their names.

TheDoctor, anecdotal or hard facts?

I have long thought about just doing carbon frame repairs rather than design

can we have an original thread please?

I've broken lots and lots of bike bits. Frames, cranks, wheels, bars. All aluminium and steel. Never broken anything made out of carbon.

I had an accident on my road bike around christmas time. Not trusting the carbon forks afterwards despite them looking fine, I replaced them. Once I had the old pair in my hands I remembered watching a video of some chap hitting a carbon frame and a steel frame with a hammer. The steel one came out a lot worse. So I decided to try for myself.

After some proper hard wellying with a lump hammer, all I'd managed to do was knock some of the laquer off the forks. The carbon wasn't even dented.

A place where I used to work were making there own CF road bike with a well known bike manufacturer, in the process we cut up several brand new CF road frames they supplied and they all had cracks/de-laminations. I would never ride CF after I saw that.

I have a mojo frame waiting to be built up.. but now i'm not so sure... yes, seriously...

I know a man who smashed the buggery out his mojo in a very low speed stack on northshore, got a replacement from IBIS (for a knockdown price)and sold it as fast as possible, then went back to alloy.

Hope that helps 😆

So the way really is CNT

Thanks Tazzy, ebay advert appearing next week.

So the way forward really is[s] CNT[/s] carbon, no thanks...

FIFY

Rickmeister - Please tell me your decision to abandon a carbon frame is based on reliable evidence and not the random ramblings and opinions found on this forum!

CNT is good if you want something which may be as harmful to health as asbestos when it comes to the manufacture of it and any cutting of bars etc.. there is a lot of research being undertaken by various occupational health and safety groups and research bodies around the world.

at least cutting some alloy bars to length isn't going to give you pleural plaques in your lungs in the future 😀

Well its either that or smoke weed (your local lbs) or fire ak47's at someone

aluminum production isn't all smiles...

brain clouds anyone?

Ali swing arm failed on my Heckler (Pinch bolt type) which was coming up to 3 years old and more recently the rear end on Yeti ASR 5 which was 3 months old failed big time. Not to bothered though as both were replaced under warranty from Santa Cruz and Yeti. The way in which the carbon rear end went though was a bit worrying and it pains me to say it that others did tell me so prior to shelling out arond £1700 for the frame.
Oh well, i'm on to a 2011 575 now so watch this space 😆

You can make stuff badly out of any material.

As for longevity - does carbon not have good fatigue properties?

Hey laney 😉
[img] http://t2.gstatic.com/images?q=tbn:ANd9GcR5A1sZBi7lTrXVO_UfvEniRcU_sLvX4xKnK4nTi3wF5c-gCC-c&t=1 [/img]
[img] [/img]
[img] http://t3.gstatic.com/images?q=tbn:ANd9GcSUK7pf8AqH8grDp-UukNgv_0fytY9Rq0FngNzHQGFh4kG77c9_zw&t=1 [/img]
[img] [/img]

carbon has excellent fatigue properties.

It also allows you yo tune the flexibility with the material as well as shape so you can prevent overly stiff areas which can lead yo failures.

As for CNTs - there is hundreds of research programs all over the world (I am doing one right now) around CNTs in epoxy resin. The benefits of CNTs in carbon fibre laminates is still not fully understood or optimised or used to it's fullest. You can apply the CNTs to the fibres to make them hairy or in the resin to change it's properties and you can do lots of stuff like functionalisation to change the bonds.

I worry about consumer products with CNTs in - especially ones that people cut. They should be fully enclosed in resin so not really a problem but there is a risk. We have to incinerate all waste with CNT contamination.

Easton used to slap Zyvex CNT logos all over their stuff (zyvex has been in the industry for years doing CNT dispersions and resin). Recently they seem to have dropped the logos from their 2011 monkeylite and Haven ranges and I would like to know why. I suspect they are using a new resin system that is better than the old one with the added CNTs. As a nano technology specialist I shouldnt be downplaying them but sometimes other things are better - it is my job to make the nano stuff even better again.

After much resurch(down the pub) i've com to the conclusion that its mainly the junctions between two materials ie carbon and ali that are the main points of failure and after talking to a guy who repairs wheelchairs, which often use the same materials,he has often found that there's oxidisation on the ail surface that causes the bond to break.So my conclusion is stick to one material and all will be well in your world.

🙄

This thread is like a Jeremy Vine show!

Having abused my Kinesis XCPro3 for a year now with alu and carbon and EVEN interefaced 😉 I love it..... I have had 2 road frames, one with cracks but thought to be lacquer and one fork which cracked on first ride but all replaced, no injuries and still ride carbon as well as Alu bikes.....

I've got some 1996 PACE RC36 forks which are carbon and still going strong.

My ally 2005 Gary Fisher FS bike has Carbon seat stays and still hasnt snapped either.

Perhaps I am doing some thing wrong?

A material that you can slice with a Stanley knife, in mind isn't tough enough for throwing down rocks.

Tell that to Continental, Kenda, Maxxis etc...

I've got a carbon Spesh Roubaix roadie that's got a witness crack in the thick brittle paint on one chainstay where the carbon tube joins the alloy dropout. I ride it with the tyres at 110 lbs, the wheels are pretty stiff Ksyriums. Local roads are shite, with loads of worn out top dressing and the odd cattle grid thrown in. The witness crack hasn't grown at all in 2 years (I have close up photos) and the frame still rides like a dream, smooth, light, fast and flattering. I don't worry about it breaking because I reckon it's waaaay stronger than I think. If I ever hear creaking I will inspect it again (often do) and make a decision. Until then I will carry on thrashing it as I struggle to keep up with my riding buddy.

daznal - Member
After much resurch(down the pub) i've com to the conclusion that its mainly the junctions between two materials ie carbon and ali that are the main points of failure and after talking to a guy who repairs wheelchairs, which often use the same materials,he has often found that there's oxidisation on the ail surface that causes the bond to break.So my conclusion is stick to one material and all will be well in your world.

good pub research - stick with one material for parts like that. Using 2 materials is sometimes needed though:

Any good engineer knows that using carbon and aluminium in contact is a no-no. They are too far apart in the galvanic series.

a lot of carbon bikes have aluminium BB and headset fittings in the frame - done properly they will be wrapped in glass and epoxy before bonding the carbon fibre around. This saves the nasty corrosion. This approach is hard to do on slender seat stays and the like.

Glass wrapping is the old way of doing it now things are so much better...
I just started repairing bust bikes as opposed to busted other carbon things.it seems people don't want to bin their investment.not surprisingly the poor understanding and old wives tales are still pretty much the standard by which carbon is judged

Poor design is nearly always evident in busted things....however sometimes it's human error when processing the stuff

All depends on the manufacturer and method of manufacture.

All frame materials can break if abused or crashed.

My old Giant XTC Composite felt bullet proof - beautifully made, light and tough as old boots.

To be fair if I were to buy a carbon MTB it would be from one of the big three, they've been knocking out carbon frames for years and have impeccable warranties/customer service.

Although I would rather like a Maxlight XC Pro3 frame.

I broke my Whyte 19c. Well, I say I say I broke it, one of the cable guides de-bonded. Two things impressed me. The first was the painless replacement process (ignoring the time it took for the frame to arrive), the other was that the guides are no longer bonded.
Hats off to ATB sales for their customer service.

I also managed to destroy an Easton EC90 SL riser. Well I say I destroyed it, the bike it was fitted to fell off the roof rack at 50 mph. Again what impressed me was the bar took a direct blow, but all the damage was caused by the levers rotating and digging in to the carbon. They were otherwise intact.

Andyl, thanks. I wondered why the CNT logos had gone of the 2011 SL bars

So carbon is great - when applied / designed / manufactured correctly - just like any other material.