Carbon... Fragile???

Cookie91

Apologies i understand this has been debated many times, but from most posts i have seen that debate seems to resolve around weight or performance.
I am currently in the market for a new bike (RIP old one), having limited space i can only have one bike. My query is for a budget of approx. £1600 i am pushing the entry carbon market / high end alloy bikes. I would just like to know peoples experiences around carbon when racing? I haven't got the budget to be replacing a frame set everytime I crash.
I am swaying towards alloy since crashes are inevitable when racing and i'm rather paranoid about how brittle carbon is. Also i don't seem to notice much weight difference between this price bracket in the two materials.


For those that care the two bikes i am comparing are:
the new madone 2.3 (alloy) with a upgraded wheel set, and a double crankset. (£1600 with upgrades)
Lapierre helium 100 double ( Carbon - no changes) (£1600)

VTech

I dont know enough to answer your question but my wife has a lapierre alloy bike thats as light, maybe lighter than my carbon felt. Looks stunning too.

Grill

When you buy a good carbon frame, you're not just buying it for weight. Stiffness and response are the main reasons as alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road.

In terms of carbon being brittle, hate to be the one to tell ya bud, but everything breaks- carbon is just more spectacular when it happens. Also, good carbon is way stronger than any alloy bike. Search YouTube for the Santa Cruz vid where they put carbon to the test. It may look weaker as it shatters whereas alloy compresses and folds, but banging out a metal frame to straighten it doesn't mean that it's suddenly fit to ride.

lc1981

I think there's a lot to be said in favour of high-end aluminium compared to relatively cheap carbon, but I wouldn't go thinking that aluminium is more durable or crash resistant. See this video.

crikey

alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road.

This is utter rubbish.

Alloy frames have been spoken of as harsh and stiff for at least the last 15 years, so do give over.

If I was still racing, I'd get a relatively cheap alloy frame and ride it like I stole it, then you have no performance disadvantage, and if it dies in a crash, it's not an issue.

Grill

crikey wrote:

alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road.

This is utter rubbish.

Alloy frames have been spoken of as harsh and stiff for at least the last 15 years, so do give over.

If I was still racing, I'd get a relatively cheap alloy frame and ride it like I stole it, then you have no performance disadvantage, and if it dies in a crash, it's not an issue.

Except it's not. It's most evident on climbs. My Foils are eager to go up hills. When I press down on the cranks they instantly go up. On all alloy bikes I have and have ridden there is always a marked delay (hesitation) as regardless of stiffness, there is still absorption on a much more noticeable level than a carbon frame with the appropriate layup.

crikey

It's still rubbish.

Cookie91

lc1981 wrote:

I think there's a lot to be said in favour of high-end aluminium compared to relatively cheap carbon, but I wouldn't go thinking that aluminium is more durable or crash resistant. See this video.

Slight eye opener, i knew that carbon is strong under tension and compression, but i thought it was shocking under impact.


With respect to carbon and a suitable layup. Am i realistically going to achieve a nice layup within my price range. A scott foil or a madone 7 series for example will be top of the range carbon. Is a relatively lower grade carbon still as crash resistant as alloy.

trooperk

On all alloy bikes I have and have ridden there is always a marked delay

May be all your alloy frame bikes are flexy.

proto

If you are racing, you will crash, it's inevitable. You might not break your bike but you will probably damage it, and if it was an expensive Colnago C59 you will cry.

So, buy a second hand carbon frame and use it for everything. If it breaks just go and buy another one and swap all your components over. Repeat ad infinitum.

I bought a used Ridley Excalibur frame to race Hillingdon crits on. It cost me £325 and it is all you'll ever need.

proto

PS this is always worth watching

http://www.youtube.com/watch?v=-lsDXEEUlRE

Gabbo

Grill wrote:

crikey wrote:

alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road.

This is utter rubbish.

Alloy frames have been spoken of as harsh and stiff for at least the last 15 years, so do give over.

If I was still racing, I'd get a relatively cheap alloy frame and ride it like I stole it, then you have no performance disadvantage, and if it dies in a crash, it's not an issue.

Except it's not. It's most evident on climbs. My Foils are eager to go up hills. When I press down on the cranks they instantly go up. On all alloy bikes I have and have ridden there is always a marked delay (hesitation) as regardless of stiffness, there is still absorption on a much more noticeable level than a carbon frame with the appropriate layup.

I agree with this. Having ridden a friends Allez and my old Tarmac, I can definitely say that the Tarmac (being a carbon frame) was by far more responsive.

john1967

crikey wrote:

alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road.

This is utter rubbish.

Alloy frames have been spoken of as harsh and stiff for at least the last 15 years, so do give over.

If I was still racing, I'd get a relatively cheap alloy frame and ride it like I stole it, then you have no performance disadvantage, and if it dies in a crash, it's not an issue.

Do you steal lots of bikes? Please don't steal mine I worked really hard to afford it.

crikey

Again, rubbish.

The pair of you are ascribing characteristics to a frame material while ignoring all the other things attached to the frame, and all the other reasons for a bike feeling the way it does.

Drop your tyre pressures by 10 psi; you'll get a more significant change in 'feeling' than the frame material.
Ride a 12 year old carbon frame then a new carbon frame; you'll get a more significant change than between alloy and carbon.

Ride a new alloy frame, ride an old gas pipe alloy frame; more difference than between the same frame in alloy or carbon.

You're only fooling yourself...

ooermissus

lc1981 wrote:

I think there's a lot to be said in favour of high-end aluminium compared to relatively cheap carbon, but I wouldn't go thinking that aluminium is more durable or crash resistant. See this video.

Great video.

pkripper

I'm in agreement with Crikey here, i have ridden a lot of bikes, both carbon and aluminium and it's entirely dependent on the frame design and build, and to an extent the components on it. I've ridden some real doggy carbon bikes and some amazing ones, and plenty of average ones in between. And there's some very very good aluminium frames out there. And at the budget being talked about initially, I'd be looking at a decent alu frame and better spec than carbon at the same. Probably a Caad and uprate the wheels.

Oh, and to say something as generic as "alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road" is not very helpful, as it's like saying all cars drive the same because they all have wheels.

Monty Dog

The SantaCruz video more than adequately shows why carbon is more durable than aluminium alloy - alloy is pretty rubbish for impact damage and fatigue, it's only good property is cheap. I've got a Battaglin carbon frame that's taken a battering over the years - even rear-ended a Disco, but apart from the chunks out of the gel coat, it still rides fine. If you want something more durable look at titanium or steel.

Gabbo

Isn't titanium generally better than ALU?

lawrences

No titanium is actually heavier than aluminium but it's stronger so less is used.


I would suggest buying a carbon bike with a high end frame and low end components with a view to upgrading.

I got my felt ar4 with the same frame as the pricier ar2 but with a pair of the softest most sluggish wheels I've ridden in a long time. They've got me through a winters training and now I can happily upgrade the wheels knowing it will make a difference.

where as if I'd got a high end alloy bike there's not many performance upgrades left to do at that price range.

pkripper

Gabbo wrote:

Isn't titanium generally better than ALU?

it depends entirely on what you want to use the bike for, and correspondingly, how the frame is designed.

greasedscotsman

Cookie91 wrote:

For those that care the two bikes i am comparing are:
the new madone 2.3 (alloy) with a upgraded wheel set, and a double crankset. (£1600 with upgrades)
Lapierre helium 100 double ( Carbon - no changes) (£1600)

Err, the Madone has a carbon fork...

zx6man

fragile, maybe not but they recommend replacing after 3 yrs.... :shock:

crikey

Trek have a lifetime warranty for frame and fork, and they honour it...

Grill

pkripper wrote:

I'm in agreement with Crikey here, i have ridden a lot of bikes, both carbon and aluminium and it's entirely dependent on the frame design and build, and to an extent the components on it. I've ridden some real doggy carbon bikes and some amazing ones, and plenty of average ones in between. And there's some very very good aluminium frames out there. And at the budget being talked about initially, I'd be looking at a decent alu frame and better spec than carbon at the same. Probably a Caad and uprate the wheels.

Oh, and to say something as generic as "alloy frames will dampen your inputs and absorb your energy instead of instead of directly translating it to the road" is not very helpful, as it's like saying all cars drive the same because they all have wheels.

This is why I qualified my statement by stressing the quality of the carbon frame. A cheap carbon frame won't ride as well as a top end alu, but you go top of the range on both and there's no contest.

crikey

Goalposts work so much better when they're movable.

proto

To put this into perspective, last season I watched a race where some Polish fellow turned up with an old steel bike, down tube shifters, very retro, and (like the rider!) quite elderly compared to some of the blingtastic kit on display.

Needless to say, he gave the rest of the field a real hard time, easily sitting on, or near the front. Top ten finish.

It's not about the bike!

pkripper

crikey wrote:

Goalposts work so much better when they're movable.

Lol, still can't see the qualification myself.

Grill

Grill wrote:

Except it's not. It's most evident on climbs. My Foils are eager to go up hills. When I press down on the cranks they instantly go up. On all alloy bikes I have and have ridden there is always a marked delay (hesitation) as regardless of stiffness, there is still absorption on a much more noticeable level than a carbon frame with the appropriate layup.

There's the qualification. Apologies for not making it evident for some, but I was under the impression (wrongly) that I didn't need to spell everything out.

thegreatdivide

If you're worried about carbon being fragile don't buy a carbon bike. No point spending your ride convinced your bike is about to crumble under your ar$e.

I'm off out now for an 80 miler on my...carbon bike!

Cookie91

greasedscotsman wrote:

Cookie91 wrote:

For those that care the two bikes i am comparing are:
the new madone 2.3 (alloy) with a upgraded wheel set, and a double crankset. (£1600 with upgrades)
Lapierre helium 100 double ( Carbon - no changes) (£1600)

Err, the Madone has a carbon fork...

A fork is cheaper to replace than a frame... Most alloy frame sets use carbon forks.

When it comes to ride quality stiffness etc. my local bike shop will let me test ride. What they won't do is test crash one obviously!
All these videos are fantastic, but has anyone actually crashed their precious carbons /alloy. These videos do seem to be rather selective, in 30 seconds i found this german video that shows the opposite in testing http://www.youtube.com/watch?v=nvk63bmVpck

greasedscotsman

Cookie91 wrote:

A fork is cheaper to replace than a frame... Most alloy frame sets use carbon forks.

OK, fair enough. I think the Great Divide is correct, if it worries you, don't get carbon.