I might go back to an aluminium frame (from carbon)

[Polisman]

Smart buttock! Oh my!

Though if there were any evidence to suggest CF frames suffered in this way there would surely have been a mass of well researched proof in the near 40 years since the Look carbon frame first appeared in the Tour de France..

No such evidence exists. Ergo.. Smarting buttocks

[Brucey]

if you asked an engineer to come up with 'synthetic wood' the end result would probably be something very much like CF. It is different from wood of course but it shares many of the same characteristics, both good and bad.

The notion that 'there would be lots of researched proof if there were a problem' is based on shaky ground. It relies (wholly or partially) on other similarly shakey ideas e.g.

- that CF is somehow all the same or at least all comparable (it isn't, any more than mahogany is comparable to balsa wood)
- that all ostensibly similar parts from the same manufacturer will be identical (they won't be, any more than -say- the same meal in the same restaurant will always taste the same)
- that it is in someone's interest (someone other than the manufacturer) to spend a fortune on the required testing to 'prove' that there is a problem
- that even if such testing is carried out you will get to hear about it.

One thing is for sure and that is that you won't read anything like this in the cycling press; they won't bite the hand that feeds them.

I happen to think that CF is a fantastic material which offers a real performance advantage in some situations. I also think that the vast majority of folk that buy CF bikes might think they need 'performance' but that in reality there are lots of other ways they could better spend their time and money on if they really wanted to go faster. I also think CF has some characteristics that mean that it is unsuitable for many people's uses; e.g. specifically

- it is fairly easily damaged
- damage isn't always evident
- damage doesn't need to be that bad before it will soon propagate into a failure
- the failure modes tend to be somewhat abrupt and unforgiving

AFAICT there isn't a single manufacturer that hasn't had to instigate a recall because they have sold CF parts that turned out to be faulty: this simple fact makes a mockery of the idea that the processes are always tied down to the nth degree and that in-process inspection/QA will catch 'bad product' before it leaves the factory.

https://www.bing.com/images/search?q=broken+carbon&FORM=HDRSC2

cheers

[Spinners]

Bang on trend (well, within this thread anyway) I've just bought a Cannondale CAAD Optimo (Tiagra spec') reduced from £900 to £535 at Evans 'Black Friday'. I've often lusted after a Cannondale since Cippo' rode a CAAD 3 and whilst the Optimo isn't a CAAD 12 or CAAD 13 it scores highly on my 'bang for the buck' index at this price. I'm going to take the wheels off and use them on my commuter and slot in some Shimano RS-010 (105) wheels that have been sitting in the corner of my office for about two years.

[MikeF]

They say aluminium has come a long way and modern frames are better than ever - but is a like-for-like aluminium frame going to feel about the same in terms of how bumpy it feels compared to a carbon one?

Who says - Marketing people? In my view aluminium frames don't ride like steel ones.

[Mick F]

I have never ridden a bike that didn't have a steel frame.

Just thought I'd add that statement to this thread.

[NickJP]

I have bikes with CF frames, aluminium frames, steel frames, and titanium frames (I basically have too many bikes). Ignoring weight, the nicest frames to ride are the steel and titanium frames (on all of which I have steel forks). With the same tyres inflated to the same pressures, those frames absorb a lot more of the buzz from indifferent road surfaces than do the CF and aluminium frames I have. Maybe a lot of that difference is down to the forks, as the CF and Al bikes have CF forks. But if I want to go out for a long ride of several hours or more, the steel and Ti bikes are a lot less tiring to ride.

[Manc33]

CF can take an absolute hammering, fatigue-wise. Maybe not in a crash, but in such a crash the same thing is going to happen to metal anyway. I saw a video (GCN or whatever cycling channel) putting weights on drop handlebars, all done in a controlled environment, the carbon bars came out slightly better than the metal ones on fatigue tests, but did slightly worse in a crash test.

I love how boingy CF is. Ever dropped a piece of carbon tubing on a hard floor? It bounces like crazy. It's really weird stuff.

This is the vid:
https://www.youtube.com/watch?v=0stL5Q9b_oo

[Smudgerii]

That’ll teach me to cast pearls before swine I guess. You don’t understand it, that’s fine. If you want to be a smart buttock, try to be more of the former and less of the latter.

What I understand is, you made claims you cannot back up, imo that makes you the “smart buttock”. Before offering me advice what I should “try to be” it would perhaps be best to sip a little of your own medicine.

If, and it’s a big unproven if, CF behaves in the manner you claim. Then why do they manufacture highly flexing items in it? How are race teams like HRC, Ducati Corse able to build in varying amounts of flex and yet remain safe? Motor manufacturers build road cars for the general public to buy?

Surely you have a link that proves your assertions? Or else why would you make them?

I do enjoy a flounce-out by a Duchess of Pout after she is caught claiming to be The Queen.

Cugel, a pedantic gluteus maximus.

Disappointed he has mot returned with some valid data... always willing to learn me.

[mattheus]

CF can take an absolute hammering, fatigue-wise. Maybe not in a crash, but in such a crash the same thing is going to happen to metal anyway. I saw a video (GCN or whatever cycling channel) putting weights on drop handlebars, all done in a controlled environment, the carbon bars came out slightly better than the metal ones on fatigue tests, but did slightly worse in a crash test.

I love how boingy CF is. Ever dropped a piece of carbon tubing on a hard floor? It bounces like crazy. It's really weird stuff.

This is the vid:
https://www.youtube.com/watch?v=0stL5Q9b_oo

What makes you think this stuff wasn't faked? It's easy to fake the data on camera.

[Brucey]

Disappointed he has mot returned with some valid data... always willing to learn me.

if the QA systems in place do not result in a perfectly consistent product, testing is (mostly) an expensive waste of time; the results could be better or worse than expected.

cheers

[hamster]

I always wonder how many of the failure photos are counterfeit frames, of which there are plenty.
That said, a pal of mine has broken three MTB frames (from a reputable brand) in two years, with warranty replacement each time. He's aged over 60 and rides tracks in the New Forest, doesn't jump, hop or do anything at all extreme. It's worrying. I also watched someone write off a road frame on the IoW Randonnee after coming off on a roundabout and sliding into a kerb. It wouldn't have totaled my metal bike.

In the marine industry there were a lot of carbon structure breakages in the early days. It was especially in offshore racing catamarans: shock loadings were not well understood with some dramatic break-ups (boats like We/Sebago and Team Philips). The bike industry is clearly still at the early place on the experience curve.

[Cugel]

CF can take an absolute hammering, fatigue-wise. Maybe not in a crash, but in such a crash the same thing is going to happen to metal anyway. I saw a video (GCN or whatever cycling channel) putting weights on drop handlebars, all done in a controlled environment, the carbon bars came out slightly better than the metal ones on fatigue tests, but did slightly worse in a crash test.

I love how boingy CF is. Ever dropped a piece of carbon tubing on a hard floor? It bounces like crazy. It's really weird stuff.

This is the vid:
https://www.youtube.com/watch?v=0stL5Q9b_oo

What makes you think this stuff wasn't faked? It's easy to fake the data on camera.

Ooooh! I will now cease to regard any camera-mediated data as reliable or representative of even the small truths we humans may comprehend, since all of it may, in your startling opinion, be fake. Should I be suspicious of my own machina, do you think? Is it colluding with some demi-god behind a curtain to show, for example, only an idealised Brechfa Forest rather than the smoking ruin it really is?

I think we should be told!

Cugel

[mattheus]

Please don't be startled Mr Cugel! Just sit yourself down with a big mug of herbal tea (and a dog to keep your feet warm), and read-up on the subject:

viewtopic.php?f=15&t=105564&start=15#p1006692

[Manc33]

Carbon rear dropouts wear away over time. Doesn't happen with metal.

Thomson won't make seatposts out of carbon (why bother when they can make a 410mm long setback metal one at 250g).

Let's build a case against carbon to justify getting a shiny new aluminium frameset.

Even the lighter weight of carbon doesn't really attract me to it, because the weight difference isn't enough to, I just want to be comfy on my bike. Part of wanting to be comfy includes knowing aluminium gives a harsher ride than carbon so I tend to err towards a carbon frame, but they are twice the price at least.

I have seen China carbon frames (without fork) for under £170 delivered to the UK. Those are going to be the ones that break IMO. Other carbon frames there cost nearly as much as one does here, getting up near to £500 for the frameset. Why risk it if you can get one for that here in the UK, that at least has a name on it and can be returned if there's a problem. Last I checked it costs £125 to send a bike frame to China from the UK. In other words you're just not going to bother sending it back even if they honour some sort of warranty. It's not likely China is going to pay the postage on that even if they are in the wrong.

When you go with a trusted China company you're just paying 90% of the UK price for one so why bother with China.

[dim]

The best aluminium bike that I have ever owned .... a Specialized S-Works Transition time trial bike that was converted to a road bike ... E5 frame

this bike weighed under 7Kg and had crappy wheels but this bike fitted me like a glove, very comfortable and smooth ride and was extremely fast both on the flats and hills

I was a fool to sell, and always wonder how much better it would have been with proper wheels and good tubeless tyres