Carbon Fibre vs Aluminium

petemadoc

I've recently got back into cycling and originally bought a focus mares cyclocross bike about 12 months ago as a 'do it all' bike. It's an aluminium frame and spends most of it's time with 23mm road tyres on.

I was thinking of selling it and upgrading to a carbon fibre road bike. The weight reduction will be 2Kg max but I was wondering what if any difference there will be and am I at any disadvantage by not riding a carbon bike.

There's a few focus cayo TR left in my size on wiggle and the spec on these looks amazing.

Should I shouldn't I?

MrChuck

The fact that one bike is carbon and one's aluminium doesn't really mean anything in itself. There are plenty of threads on this very subject. But going from a cross bike to a road bike would make a difference.

petemadoc

MrChuck wrote:

The fact that one bike is carbon and one's aluminium doesn't really mean anything in itself. There are plenty of threads on this very subject. But going from a cross bike to a road bike would make a difference.

Yeah I should have asked this too, what kind of difference will that make. I checked out the different geometry between the focus mares cross bike and the aluminium race equivalent and the top tube was just 2cm shorter on the mares so I can't imagine the riding position is much different. I can keep up with road bikes out on club rides and stuff no problem.

volké

It depends very much on the quality of the frames. A high-end aluminium frame can be more comfortable than a low or even mid-range carbon frame. You have to look at whether it's a quality carbon frame or whether they're just using carbon to 'tick a box' on most people's checklist when buying a bike.

I ride an aluminium frame with a carbon fork and don't have any issues with it being uncomfortable, and it's geometry is quite aggressive too. It's even competitive on weight with some carbon frames at a similar price.

So don't discount aluminium altogether, but if you can find a good quality carbon frame it definitely has its advantages over aluminium.

Anonymous

Or buy second hand good quality carbon fibre frame. I just sold my Cervelo S2 frame, which was amazing, for over a grand less than RRP and it was only 8 months old in immaculate condition...

petemadoc

Good idea NapD

I had a look on ebay and found this

http://cgi.ebay.co.uk/carbon-bike-frame ... 514wt_1137

What's the deal with OEM bikes like this, should I steer clear?

I know I'm asking the same question again but what's the difference between carbon and aluminium, is it all about weight?

porker33

Not necessarily all about weight, there is a thought that carbon helps reduce some of the road buzz you can feel through the frame which can add some fatigue over a longer ride.

There is no easy answer as a top quality ali frame may well be superior to a lesser quality carbon version.

Obviously geometry and intended use of the frame will have some influence with how it rides for you.

I had a decent ali frame, now have a decent carbon frame from the same manufacturer....carbon seems slightly stiffer when you kick the pedal and road buzz is less, also slightly lighter.....so a marginal improvement for a considerable increase in expense.

One thing though, if you do get an ali frame.......you will always be wondering what a carbon frame would have been like?

Mister W

Tyres do a far better job of absorbing road buzz than any frame, as does decent bar tape and padded gloves.

Frame material has far less influence on the way a bike rides than everyone pretends. Any material can be made stiff, comfortable, flexible or whatever you want so ignore the material and find a bike that you like.

volké

Since this will be your first 'proper' road bike, you could also get a cheaper alu frame and if you find that you use it very regularly, get a carbon bike next summer and keep the alu one as a winter bike (because in winter you're more likely to crash and an alu frame will hold up much better).

Anonymous

Mister W wrote:

Tyres do a far better job of absorbing road buzz than any frame, as does decent bar tape and padded gloves.

Frame material has far less influence on the way a bike rides than everyone pretends. Any material can be made stiff, comfortable, flexible or whatever you want so ignore the material and find a bike that you like.

However, I find a good carbon frame is comfortable yet stiff. I find my Carbon bike absorbs road buzz better than my supposedly comfort oriented Ti bike (using same contact points)...

It's also stiffer.

That's not to say the Ti isn't good, it's great!

Both are 'high end' FWIW...

desweller

The ratio of yield strength to elastic modulus is comparitively high for CFRP compared to aluminium. This means that, in order to build a frame out of aluminium that will be strong enough, it will be stiffer and consequently better at communicating high-frequency vibration than CFRP.

Steel also has a higher elasticity/strength ratio than aluminium, hence a good steel frame can have similar qualities.

EDIT: The caveat is of course that design plays a not inconsequential role in all this, especially with CFRP, which is not as straightforward to work with as metal.