# Carbon Frames Are they really needed.



## miremare (17 Jul 2011)

Hello

im looking at a road bike.

my budget is £1500 tops.

as an example im looking at a 

*Cube Agree GTC Pro 2011. ( given weight is 8.3kg ) carbon*
vs


*Cube Agree SL 2011 ( given weight 8.1kg) triple butted non carbon
*

both have the same spec ( apart from carbon frame)


is carbon really giving a massive advantage for a bike around £1500


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## Evil Rabbit (17 Jul 2011)

I have only limited experience of CF frames, but to me they ride differently and it comes down to personal feel/preference. I would have no issue buying an Ali frame or a CF - it would depend on which ride I preferred.


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## xxmimixx (17 Jul 2011)

ohhh lucky youuuuu I'd love a Cube bike they are stunning!


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## smokeysmoo (17 Jul 2011)

IMHO, and after 5 years carbon ownership consisting of a Trek Madone 5.5, a Focus Raven MTB and a Focus Cayo Pro, NO. 

Check THESE out instead


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## brockers (17 Jul 2011)

smokeysmoo said:


> IMHO, and after 5 years carbon ownership consisting of a Trek Madone 5.5, a Focus Raven MTB and a Focus Cayo Pro, NO.
> 
> Check THESE out instead



Are you on commision?


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## smokeysmoo (17 Jul 2011)

brockers said:


> Are you on commision?



You'd think wouldn't you  
Truth be told, I just can't praise the CAAD10 highly enough, but you've probably figured that out by now


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## JonnyBlade (17 Jul 2011)

Try a Boardman


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## Fletch456 (18 Jul 2011)

Cannondale are known for building fantastic aluminium frames. It's a sign of how much they believe in them and how much interest there is when they sell one for £2500 too.

Though I recently got my first carbon, though my alu was 7 yrs old and ok but not the best. The Trek 4.7 I bought is a lot more comfortable and faster and a pleasure to ride.

A pal is a long term fan of Cannondale and has a CAAD that was about 10 years old but has just got his first carbon. I rode with him when he went on his first ride and he fell in love instantly - faster and smoother over bumps and manhole covers for him too.

He stuck with Cannondale - got something a bit above your budget in the Super Six 105 at £1800. I had a very short ride on it and the ride is a just a bit more to my taste than the Trek as it's just a little bit sharper. I'd have definitely looked at and tried the Cannondale but they were too late getting into the shops, which I've found out was due to their process of changing distributor this year.

You quoted weights above and I was kind of focussed on this and I still pick up bikes when a pal gets a new one but I know it's more about other things too now. Like the feel of the ride and how well it fits you or is fitted to you. I don't give it the priority I did before. The alu bike I didnt test ride when I bought but totally endorse trying a few bikes and may have missed THE best value for money on bikes I couldn't test ride or were too far away for me to try. I really wanted to remove the rough feel I was getting from the alu as a result of feeling every tiny bump in the road.


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## Black Sheep (18 Jul 2011)

No, carbon frames are not needed.

my steel framed tourer is the same weight as my friend's specialized carbon racing bike and in my opinion, nicer to ride 

don't bother with alu either - thats like taking a BMW M3 with its harderned sports suspension and stiffening the ride some more!

steel is good, very good.


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## amaferanga (18 Jul 2011)

As I understand it the Agree GTC Pro is Shimano 105 where as the Agree SL is Ultegra. The Agree SL also has better (read lighter) wheels and probably some other bits are a bit better/lighter hence why the weights are so close. 

If this is your first decent road bike then I duobt you'd be disappointed in either, though you might want to look at the Planet X SL Pro and Planet X Nanolight. Think there's an offer on the SL Pro at the moment and there'll probably be one on the Nanolight soon (since they're currently at full price - Planet X rarely sell stuff at full price for long).


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## amaferanga (18 Jul 2011)

Black Sheep said:


> No, carbon frames are not needed.
> 
> *my steel framed tourer is the same weight as my friend's specialized carbon racing bike* and in my opinion, nicer to ride
> 
> ...




Really? There must be some seriously heavy components on the Specialized and/or some seriously lightweight bits on your tourer. I bet your frame/forks weighs around a kg more than his.


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## John the Monkey (18 Jul 2011)

Good and bad frames can be made out of any material - what matters is how the bike feels to you.

I ride a steel tourer that *is* heavy (but largely because it has robust wheels, large tyres, a Brooks...) but is incredibly comfortable (42c tyres'll smooth out a lot of the bumps),

I ride an aluminium frame with carbon forks that's far lighter, and more direct in it's handling, but that's at least partly because I've put lighter parts on it, and the geometry is compact, with a longer stem and lower riding position. 

I can go faster on the aluminium framed bike - I accelerate quicker (the Tourer HATES being "muscled" up to speed) and have a faster top speed. Averages are 2-3mph quicker than averages on the tourer. 

But I'd hesitate to carry more than a commuting load on the aluminium bike, and I have to get creative to fit a rack to it. I'd not belt it along towpaths or gravel like I do with the tourer either - speed and lightness in a bike isn't everything.

If you ride a few bikes, and the one that sings to you is carbon, buy that! Don't get too hung up on stuff like this.

Sheldon Brown on Frame Materials


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## Rebel Ian (18 Jul 2011)

amaferanga said:


> Really? There must be some seriously heavy components on the Specialized and/or some seriously lightweight bits on your tourer. I bet your frame/forks weighs around a kg more than his.




I read that and thought the same. I've be very very surprised if that was the case, unless you're bringing rider weight into the equation!


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## Cletus Van Damme (18 Jul 2011)

Fletch456 said:


> He stuck with Cannondale - got something a bit above your budget in the Super Six 105 at £1800.



I was at my LBS on Saturday picking up some components that I got on the C2W scheme and noticed a Cannondale Super Six Hi-MOD SRAM RED bike. I am pretty new to cycling and my Secteur is the first road bike that I have owned and I find it very comfortable but have nothing to compare it to. Where I work there are a few people that have lower end carbon road bikes and I have picked them up in the bike shed, and I have thought that they are a little lighter than my bike but I was hardly amazed by it. I also thought that this weight difference would make very little difference to somebody of my ability. Back to the Super Six Hi-Mod, I picked this up and I was amazed at how little it weighed. It had a very hefty price tag of around 3.5K but for once I could actually appreciate why such a bike cost so much. Then again as mentioned, you could maybe get an alu bike that was just as light by paying a decent amount too. I think I need to start saving.


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## dellzeqq (18 Jul 2011)

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.


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## Jezston (18 Jul 2011)

dellzeqq said:


> 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.



I thought steel was supposed to be more absorbant than carbon?


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## raindog (18 Jul 2011)

Black Sheep said:


> my steel framed tourer is the same weight as my friend's specialized carbon racing bike and in my opinion, nicer to ride


hmmmmm...... my Italian steel is 9.8 kilos and my pal's carbon bike that he races is about 7.5 kilos.


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## dellzeqq (18 Jul 2011)

Jezston said:


> I thought steel was supposed to be more absorbant than carbon?


it's about resonance. Steel resonates and carbon doesn't. 

I'm with Raindog on the weight, although I accept that the frame is but a small part of the bike, and that the weight of the wheels is probably more important.


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## John the Monkey (18 Jul 2011)

Jezston said:


> I thought steel was supposed to be more absorbant than carbon?



Depending on the tubing, geometry, you can make a pretty harsh riding steel bike if you've a mind to. Stick high pressure narrow tyres on it too, and you can probably shake some fillings out.


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## tyred (18 Jul 2011)

The traditional lugged steel frame is a thing of beauty.


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## GrasB (18 Jul 2011)

miremare said:


> Cube Agree GTC Pro 2011 ( given weight is 8.3kg ) carbon vs Cube Agree SL 2011 ( given weight 8.1kg) triple butted non carbon
> 
> both have the same spec ( apart from carbon frame)


Not quite correct, while the headline specs are the same the SL has higher spec cranks & chain plus lighter seat post, stem & bars. If you go by the list numbers the frame is about 150-200grm heaver but the lighter weight components push the weight advantage to the SL (it is an SL after all).



> is carbon really giving a massive advantage for a bike around £1500


Not really, it's more about what blend of characteristics you want. As a general rule aluminium is typically stiffer, carbon gives a more forgiving ride.


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## Baggy (18 Jul 2011)

raindog said:


> hmmmmm...... my Italian steel is 9.8 kilos and my pal's carbon bike that he races is about 7.5 kilos.



My Canadian steel roadie is about 7.5kg, and my colleague's Giant Advance Carbon doesn't weigh much less.

We could both do with losing about 7.5kg of body weight.


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## raindog (18 Jul 2011)

Baggy said:


> My Canadian steel roadie is about 7.5kg, and my colleague's Giant Advance Carbon doesn't weigh much less.


That seems unbelievable - you must have fabulous gear on it.


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## brockers (18 Jul 2011)

Perfectly doable with a 1600g steel frame and decent wheels.


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## ianrauk (18 Jul 2011)

My Carbon is a Spesh Roubaix Elite, my Alu is a Spesh Secteur Elite.
They share the same geometry and have near the same components. (105).


The Alu jobbie however is a much stiffer ride. For my commute it's fine. For much longer journeys however, I can really feel it after. It feel's like I have been put through through the grinder. The carbon jobbie I can ride all day. It's as comfy as my favourite old armchair, has less road buzz and is a much smoother ride.


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## endoman (18 Jul 2011)

ianrauk said:


> My Carbon is a Spesh Roubaix Elite, my Alu is a Spesh Secteur Elite.
> They share the same geometry and have near the same components. (105).
> 
> 
> The Alu jobbie however is a much stiffer ride. For my commute it's fine. For much longer journeys however, I can really feel it after. It feel's like I have been put through through the grinder. The carbon jobbie I can ride all day. It's as comfy as my favourite old armchair, has less road buzz and is a much smoother ride.



So why have the Alu?


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## Baggy (18 Jul 2011)

raindog said:


> That seems unbelievable - you must have fabulous gear on it.


No, a mix of Tiagra and 105. Her bell must weigh quite a bit though! 
They are both small frames, I wonder if as the sizes increase carbon is proportionally lighter, as in her bike seems to look as if it's made of all the "chunky" bits of carbon with very little tubing.


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## ianrauk (18 Jul 2011)

endoman said:


> So why have the Alu?



As I said in my post... for my commute. It's fine for that.


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## endoman (18 Jul 2011)

ianrauk said:


> As I said in my post... for my commute. It's fine for that.



Yep, I have an alu hybrid for commuting, but would much rather go on the carbon, only really ride the alu on towpaths etc now.


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## Hacienda71 (18 Jul 2011)

Come on now no one has mentioned titanium!


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## Baggy (18 Jul 2011)

Across the world of fora I'm seeing more and more reports of titanium frames failing...


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## Canrider (18 Jul 2011)

Just a passing note: why are the people making strikingly light weight claims not mentioning make/model?

Honestly, 'my Canadian steel roadie'?


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## Canrider (18 Jul 2011)

Baggy said:


> Across the world of fora I'm seeing more and more reports of titanium frames failing...


That's interesting. My understanding was that Ti worked like steel: as long as you don't exceed certain stress levels, it'll never fail. Are they building them too lightly?


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## MarcA (18 Jul 2011)

Just purchased a Carbon (Focus Cayo so at the budget end). I previously rode a steel bike and the carbon is lighter and faster (+2mph average on a long ride). However the thing that surprised me was that, with thinner tyres and an extra 20psi, it was significantly more comfortable over poor surfaces. Can't really compare with Alu though.


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## zigzag (18 Jul 2011)

i've trasferred the same components to 531c steel, triple butted alu(+carbon forks) and carbon framesets. it's not easy to compare as the bikes have slightly different geometries, so handling is not the same. correct and comfortable fit is so much more important than a frame material. tyres, pumped to correct pressure, comfy saddle and handlebars are very important too. now back to the frame materials:

steel is a fine ride, but flexes too much when sprinting out of saddle or grinding uphill. it's also quite heavy and combined with flexiness is not a great climbing bike. if nicely finished it can be a work of art.

alu bike was my partner on my longest ride so far (1000miles in 5days) and i had no issues with the comfort whatsoever. the frame was stiff which was great on big hills and mountain passes. maybe a bit harsh on rough roads, but this didn't bother me too much as i had other things to worry about at the time.

carbon framset is the lightest (about 0.5kg lighter than alu) and has a very quick steering, but flexes a bit more than alu. ride quality is similar to and maybe better than steel, climbs well due to low weight and corners like it's on rails. i've yet to take it on a long ride, but so far it seems it could cope very well. it's only a pity that carbon frames don't look very nice (usually plain or no colours and no chrome ).

in my opinion - choose the bike that fits well, with the tyres that are not too hard and the ride will be good whatever frame material (as long as it's not the cheap and nasty stuff). if seconds or milliseconds matter go for the lightest/stiffest combination possible or the one that allows to upgrade in the future.


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## Baggy (18 Jul 2011)

Canrider said:


> Just a passing note: why are the people making strikingly light weight claims not mentioning make/model?
> 
> Honestly, 'my Canadian steel roadie'?


 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. 



Canrider said:


> That's interesting. My understanding was that Ti worked like steel: as long as you don't exceed certain stress levels, it'll never fail. Are they building them too lightly?


From what I remember (it's all anecdata!) the majority have been welds failing, but definitely reports of some cracked tubes. I think vorsprung of this parish killed his after a few years of Audaxing.


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## MacB (18 Jul 2011)

Baggy said:


> Across the world of fora I'm seeing more and more reports of titanium frames failing...



yep and if you visit the right places you'll find people warning of alu, carbon and steel failures...not helped by certain 'establishments' that spout off coz they only do steel, though I now see that they offer carbon forks. I trawled for info very carefully when having a frame specced and came to the conclusion that there is no conclusion. Apart from the odd example you rarely get full detail, ie useage, rider info, weights, if it had previously been crashed, if they might have gone a bit mad with some allen wrenches, etc, etc. You don't need to look very far to find people that won't trust a carbon fork, a low spoke count wheel(I probably fall into that category), carbon bars, long seatposts and so on.

One of the joys and curses of the net, trying to weed out accurate info, from a source you can trust that has actually got proper real world data.


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## John the Monkey (18 Jul 2011)

Eh, MacB, we ALL have our luddite frontier, old chap


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## MacB (18 Jul 2011)

John the Monkey said:


> Eh, MacB, we ALL have our luddite frontier, old chap



I know, but having just shelled out for my second custom Ti frame, comments like that make me want to weep...still at least I can blame Baggy if either of my frames fails


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## John the Monkey (18 Jul 2011)

MacB said:


> I know, but having just shelled out for my second custom Ti frame, comments like that make me want to weep...still at least I can blame Baggy if either of my frames fails



Heh  I can remember some stuff about welds, and one problem with integrated headsets - both are from a while ago now though.


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## theclaud (18 Jul 2011)

MacB said:


> I know, but having just shelled out for my second custom Ti frame, comments like that make me want to weep...still at least I can blame Baggy* if either of my frames fails*



You should be fine. I think they only fail when you ride them.


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## Baggy (18 Jul 2011)

MacB said:


> I know, but having just shelled out for my second custom Ti frame, comments like that make me want to weep...still at least I can blame Baggy if either of my frames fails


Nooo, blame vorsprung! I suppose it surprises me as it _seems_ to be more prevalent than I'd have thought.

More anecdata - there was much sucking of teeth, sardonic laughter and predictions if immediate catashtrophic failure when my brother bought an aluminium Peugeot in the 80's, but it survived over 20 years of being mauled about before it finally developed a hairline crack.


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## MacB (18 Jul 2011)

theclaud said:


> You should be fine. I think they only fail when you ride them.




Now, now, back on topic, this thread is about plastic bikes after all


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## Canrider (18 Jul 2011)

Baggy said:


> 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.


..or just to buy one for themselves? I singled you out but you're not the only one. I'd have thought if the bike was so good/light/whatever people would be happy to name it, is all.



> From what I remember (it's all *anecdata***!) the majority have been welds failing***, but definitely reports of some cracked tubes. I think vorsprung of this parish killed his after a few years of Audaxing.



**I'm stealing that one. 
***That I could well believe just because Ti is said to be so tricky to weld right. Cracked tubes is a bit more scary.


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## Baggy (18 Jul 2011)

Canrider said:


> ..or just to buy one for themselves? I singled you out but you're not the only one. I'd have thought if the bike was so good/light/whatever people would be happy to name it, is all.


Point taken, though my reply was being a bit tongue in cheek as I've had quite a few comments (in real life) about why on earth I bought a steel road bike. IMO it's a shame they've been discontinued (though still available at bargain prices in the less common sizes), but perhaps the fact they're steel put people off?



Canrider said:


> ***That I could well believe just because Ti is said to be so tricky to weld right. Cracked tubes is a bit more scary.


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.


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## Rob3rt (18 Jul 2011)

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)


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## amaferanga (18 Jul 2011)

Baggy said:


> 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?


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## MacB (18 Jul 2011)

Baggy said:


> *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


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## Baggy (18 Jul 2011)

amaferanga said:


> 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!



MacB said:


> 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.


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## zigzag (18 Jul 2011)

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?


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## theclaud (18 Jul 2011)

MacB said:


> 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.


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## Baggy (18 Jul 2011)

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).


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## amaferanga (18 Jul 2011)

Baggy said:


> 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).


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## cloggsy (18 Jul 2011)

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!


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## BrumJim (18 Jul 2011)

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.


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## lukesdad (18 Jul 2011)

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.


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## amaferanga (18 Jul 2011)

lukesdad said:


> 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.


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## MacB (18 Jul 2011)

amaferanga said:


> 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!!!!!!!!!


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## raindog (18 Jul 2011)

Baggy said:


> 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.


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## asterix (18 Jul 2011)

dellzeqq said:


> 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.


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## dellzeqq (19 Jul 2011)

asterix said:


> 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.


I wasn't. I was suggesting that the only steel bike I'd ride is a Brompton. 

I rode steel bikes for decades (to John O'Groats, on day rides up to 200 miles, and through the Pyrenees), and I have an aluminium hybrid (in the garden) which is a cheap way of getting round town. And my view is that time has moved on and steel frames are for shopping - not for rides of a decent length. Hence the Brompton. 

And magnesium frames are wonderful collectors items. You can have mine for £300


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## Fletch456 (19 Jul 2011)

dellzeqq said:


> I wasn't. I was suggesting that the only steel bike I'd ride is a Brompton.
> 
> I rode steel bikes for decades (to John O'Groats, on day rides up to 200 miles, and through the Pyrenees), and I have an aluminium hybrid (in the garden) which is a cheap way of getting round town. And my view is that time has moved on and steel frames are for shopping - not for rides of a decent length. Hence the Brompton.
> 
> And magnesium frames are wonderful collectors items. You can have mine for £300



Out of interest / curiosity what are the pros / cons of magnesium frames? Not one I can recall being written about for some time in magazines. I studied materials a little bit at university though that's quite a while ago now and remember it being light but nothing else right now.


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## Rob3rt (19 Jul 2011)

amaferanga said:


> 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.



What model is your carbon bike? What size? Frame and fork or just frame? Without having some idea of the price point of your bike, any point you are trying to make is pointless.

Maybe you are missing some of the finer points in the comparison between alu and carbon.

Equivalent carbon frames and components arent neccesarily lighter, a lot of carbon components are lighter, but these usually cost a considerable amount more because they are a step above what is achievable with alu, their design has been pushed beyond what alu could achieve safely. If you compare equivalently priced items its a much better way to go about such comparisons, say for £100 how much difference is there between a carbon and alu handlebar? Not just one isolated comparison, but a good sample and look at the averages.

Equivalently priced alu and carbon frames and components are likely to be in the same ballpark with regards to weights, the carbon might be marginally lower, if its MUCH lighter than a top end alloy frame then its most likely lacking in some other desirable attribute, i.e. "stiffness". You are not just paying for material, you are paying for the design work thats gone into it and top end frames are designed more optimally than entry level bikes, often they are designed beyond the capabilies of alu and thus the carbon is essential.

Of course there will always be exceptions, or massive price hikes occasionaly due to brand names etc but this aside, if you are spending say £1k on a bike, I think you would be hard pressed to find any huge functional difference between carbon and alu. It would likely come down to feel and fit.


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## amaferanga (19 Jul 2011)

Rob3rt said:


> What model is your carbon bike? What size? Frame and fork or just frame? Without having some idea of the price point of your bike, any point you are trying to make is pointless.
> 
> Maybe you are missing some of the finer points in the comparison between alu and carbon.
> 
> ...



I was responding to a statement that carbon frames and components are not lighter than their steel/alu counterparts. The simple fact is they _usually_ are. Whether they are made the way they are for lightness or for other reasons wasn't the point I was addressing - I was merely responding to a misleading comment.

Please point me to an alu frame that costs around £600 that weighs 920g. In fact, please point me to an alu frame that weighs 920g or less - is there even such a thing?

(my frame is a Planet X Nanolight, size small and 920g is the claimed weight - I expect its a bit more, but I bought the complete bike so never had a chance to weigh just the frame)


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## Herzog (19 Jul 2011)

Weight is not the absolute here. 

Carbon can be moulded into aerodynamic shapes, therefore reducing the work the rider has to do. Should the weight of a non-areo aluminium and an aero (evenly slightly areo) carbon framed bike be same, the carbon bike would require less work to travel the same distance.


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## Fletch456 (30 Jul 2011)

I thought it worth posting that for many of us, including me, our understanding of how a material rides is limited to our experience of riding a bike made of that material.

It should also be borne in mind that it varies with manufacturer / brand and when the bike was built. So what we may think of how say alu or carbon rides may not be true for every bike of that material.

I've an alu bike that is about 7 yrs old - a Terry Dolan frame with Fulcrum 7 wheels - that has a very hard ride in my book. I can feel literally every tiny stone, piece of dirt, that is on the road. Yet I've learnt that the geometry - every stay is straight, no curves and the top tube is straight - may mean that some alu bikes don't ride like this. I know quite a few people (those I've read on here I think) really like how their alu rides yet others like a friend of my brothers, rode alu once and swore to never to return to it.

Last year I rode carbon and ti for the first time - with the ti it was like there was a layer of rubber on the road whilst the carbon suprised me with how comfortable it was (a Scott CR1) and wanted to go up the hill far quicker than the ti. It was the latter and it being more comfortable than I was expecting that sold me on carbon. Bear in mind that it was no ordinary ti bike but £4000 worth of carbon / ti mix!!! Not that I could afford it but the shop let me ride it because it was my size.

So I after that experience I couldn't imagine how people would race on ti, yet they do. There is a team called Qoroz who ride on ti bikes; ok Qoroz is a make of ti bike and it's their team so they probably have the best of the best but this was a £4000 bike that I rode. I also recently learnt of a gal who rides for a women's team and after her carbon was badly damaged during an attempted theft she replaced it with a ti and loves racing on it.

For me I am actually a little nervous about riding the alu again in the winter cos I've now bought a carbon bike and one that is too good to ride in the bad weather. It is so much more comfortable than my alu though will look out for a second hand carbon seat post to improve the ride.


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## the_mikey (30 Jul 2011)

I love both my alu and carbon framed bikes, but they feel very different to ride. I can't make claims of superior performance with one frame over another, although I regularly record higher average speeds on the carbon framed bike, that bike also has lighter wheels, lighter tyres, and lighter components. The aluminium framed bike is much less forgiving, every tiny bump in the road surface is faithfully reproduced at the saddle, my average speeds recorded on this bike are 2km/h slower, but also it has heavier wheels, heavier puncture resistant tyres and a heavier chainset.


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