Carbon Frames Are they really needed.

[Rob3rt]

This debate is somewhat hard to add to. Lets 1st clarify, what do people mean by a stiff frame? Do they mean the frame is an overly harsh ride, or that it is stiff where it matters i.e. it provides you with efficient power transfer? I would go with the latter for my definition, a stiff frame need not neccesarily be too harsh to ride, material aside. As for weight, weight itself isnt the main advantage of carbon. My understanding it that the ability to manufacture frames that can be made very strong and stiff where it is needed with either intricate shapes that cannot be achieved with other materials, or by adding larger amounts of material around choice parts like the bottom bracket without the weight penalty associated wth other materials. Carbon can be used to do this whilst also being able to soak up road buzz (Correct me if I am way off base here!).

Baring the above in mind, it becomes apparent that if you buy a cheap carbon bike, its cheaper for a reason, it has most likley not been designed to maximise the potential of the material it is made from, it will be unlikely to be lighter and stiffer where it matters than a top end aluminium bike. Cannondale are a prime example, their CAAD frames are highly evolved and have been very intensively designed using aluminium and are as light as many higher level carbon frames, they are very stiff where it matters, consequently they are a bit harsher to ride, nothing that cant be solved with some choice components and correct set up. Does this make alu better than carbon? Not neccessarily, it may or may not be better than an equivalently priced carbon frame however! Individual bikes should be judged in their individual merit, not on material type.

It comes down to budget, personal preference, geometry etc etc.


(I ride alu frames, but have also owned steel, and have test rode carbon - I have no real preference over material, just individual bikes taken on their own merit)

 

[amaferanga]

Sorry, I'd forgotten that everyone would want to rush off to Google so they could refute my claims. It's a Kona Haole, a small one. Now discontinued.

Well that's interesting. Is it the 2010 version that Kona claimed was 16.8lb? That's with Ultegra, carbon FSA chainset and Ksyrium wheels. And I would guess a full carbon fork as well. So I'm still very surprised that a mix of Tiagra and 105 would come in at 7.5kg - have you actually weighed it on trustworthy scales? Is that with pedals as well?

 

[MacB]

Without wanting to upset MacB, vorsprung's cracked along the top tube, across the weld and then up the seat tube, but at the time it seems as if there might have been an issue with a batch/particular manufacturer.

Yeah, too late there Bucko, throw in the casual savaging from TC and I'm barely able to see the screen through my fugue of anguish.

By the way I had read Vorsprungs tale so no real harm done

 

[Baggy]

Well that's interesting. Is it the 2010 version that Kona claimed was 16.8lb? That's with Ultegra, carbon FSA chainset and Ksyrium wheels. And I would guess a full carbon fork as well. So I'm still very surprised that a mix of Tiagra and 105 would come in at 7.5kg - have you actually weighed it on trustworthy scales? Is that with pedals as well?

That's the one. Edit - no, it was without pedals - we dangled it off a ReubenHeaton fish-weighing scale thing. I might now do a re-weigh for verification!

Yeah, too late there Bucko, throw in the casual savaging from TC and I'm barely able to see the screen through my fugue of anguish.

 

[zigzag]

frames of any material can fail if built/used inappropriately. over long term tests frame designers settle to the safe margins of strength but there will be instances when the frames fail even if built within these safety margins. if that happens too often they need to change the design, so the failure rate gets back to "acceptable". in an ideal world acceptable would be no failures at all, but as we probably know the world is far from ideal. specialized frames, trek carbon steerers used to have issues few years back, but now all seems ok. specialized for example now use steel handlebar stems as in their top bikes as "that's what elite riders prefer". we all want lighter and stronger (and cheaper) equipment, but going that route the possibility that something will fail increases. imagine someone builds a lightweight carbon tourer which rider loads with 30kg panniers and goes fast bumpy descent. whose fault is it if the rear triangle breaks?

 

[theclaud]

Yeah, too late there Bucko, throw in the casual savaging from TC and I'm barely able to see the screen through my fugue of anguish.

I aim to please.

 

[Baggy]

Re-weighed with pedals it comes in at 8.5kg. The pedals are about 400g and it now has a different saddle, so probably about 7.9 - 8kg without pedals and with original saddle.

Weight weenies has the frame (doesn't specify if forks inc though) at 1290g for a 58cm.

It's a lovely bike to ride, very stiff and responsive and nothing like as harsh as the aluminium frames I've tried. Haven't ever tried carbon, so I can't compare (but if anyone has a small frame they need testing, I'm open to offers).

 

[amaferanga]

Re-weighed with pedals it comes in at 8.5kg. The pedals are about 400g and it now has a different saddle, so probably about 7.9 - 8kg without pedals and with original saddle.

Weight weenies has the frame (doesn't specify if forks inc though) at 1290g for a 58cm.

It's a lovely bike to ride, very stiff and responsive and nothing like as harsh as the aluminium frames I've tried. Haven't ever tried carbon, so I can't compare (but if anyone has a small frame they need testing, I'm open to offers).

That is very light for a steel frame. A good few hundred grams less than your average steel frame I should think and on a par with some carbon frames (and probably the CAAD9).

 

[cloggsy]

I love my Boardman Team Carbon; only 7.96Kg's in its sock feet (apparently?)

Not (I hasten to add,) with all the crap I lug about on it!

 

[BrumJim]

Steel? Carbon? Aluminium? Titanium?

No, only Bamboo or Flax for me. That's when I can get the wife to agree to spending that amount of money on a bicycle.

 

[lukesdad]

It does make me laugh when people assume that a product in carbon. I s lighter than a product made from another material, because usually they are nt. As has been said earlier they are made from carbon for other reasons.

 

[amaferanga]

It does make me laugh when people assume that a product in carbon. I s lighter than a product made from another material, because usually they are nt. As has been said earlier they are made from carbon for other reasons.

Huh? So carbon frames aren't usually lighter than steel or alu? My frame weighs 920g - can you point me to steel or alu frames that weighs less? Carbon bars, stems and seatposts, etc. generally are as light as top end alu.

 

[MacB]

Huh? So carbon frames aren't usually lighter than steel or alu? My frame weighs 920g - can you point me to steel or alu frames that weighs less? Carbon bars, stems and seatposts, etc. generally are as light as top end alu.

Woot, Woot, weight anxiety alert!!!!!!!!!

 

[raindog]

Re-weighed with pedals it comes in at 8.5kg.

Well that's a bit different to 7.5 kilos all right.

But that's still incredibly light - well done. When I gave the weight of my Italian steel at 9.8 kilos, that's with pedals and bottle cages. Couldn't see the point of weighing it without pedals. Might as well weigh it without bars and stem.

 

[asterix]

I'd rather walk than ride an aluminium or steel road bike. The Brommie is fine for shopping, but if I want to feel alive and in control without having my arms turned to jelly, it's got to be carbon.

It should be noted that not all steel bikes are 'Brommies' and that 'Brommies' are folding bikes intended for the commuter!

Comparing a carbon road bike with a Brompton is disingenuous and unhelpful.