Carbon? Alloy?

[Boris Bajic]

There's a thread elsewhere about the likelihood that a broken (integral) rear hanger will write off a whole carbon frame. There are other snippets here and there about carbon frames suffering terminal cracks of one kind or another. I hear similar things about alloy frames - although over a longer period.

I recall the advent of carbon boats in rowing (mid-70s) and the horror stories about two-year lifespans. It seems to have come to nothing.

But... as I look around the garage, I see that although we have not 'carbonised' as a cycling family, there are several pairs of carbon forks, a few seatposts and some carbon stays in the family fleet.

And there at the back is my ancient steel fixopholous fixed-gear fixie. Steel. Ancient. Good as new.

If ridden fairly regularly, what is the realistic lifespan of a carbon frame?

If dropped at speed, will any fractures or post-crash weaknesses in the carbon be visible?

My steel fixie has been straightened by cold press twice in its long life and still tracks like an arrow.

Will I be riding my nice alloy-carbon framed 2008 road bike in another five years? Ten years?

Are the days of this sort of longevity now gone?

 

[smokeysmoo]

I'm not a fan of carbon myself, but even I can't argue with the tests in this video,

http://www.pinkbike.com/news/santa-cruz-bicycles-test-lab.html

If carbon's your bag then you'll have nothing to worry about IMO

 

[YahudaMoon]

Bicycle Frame Test Carbon vs Aluminium vs Steel​

 

[biggs682]

steel all the way for me

 

[fossyant]

Things break sometimes, or they don't. Simple.

 

[S1mon]

Well I love my carbon but never really thought about attacking it with a grinder !!!

 

[Smokin Joe]

If carbon and aluminium were as weak as (certain) people make them out to be you would not be able to take part in races or sportives without seeing them break under riders at regular intervals. They don't.

Either material will last for as long as you want to keep the bike.

 

[Mr Haematocrit]

I'm pretty certain that should Carbon not show the strength required then it would not be so widely used in motorsports.
I would also have thought that professional cycle races such as paris roubaix would place unusual vibrational stresses through frame sets at a range of frequency's. I would have believed that this would show up any major weaknesses in materials yet the most common frame material used for this event is carbon.

 

[raindog]

Things break sometimes, or they don't. Simple.

what he said

 

[ianrauk]

I'm pretty certain that should Carbon not show the strength required then it would not be so widely used in motorsports.
I would also have thought that professional cycle races such as paris roubaix would place unusual vibrational stresses through frame sets at a range of frequency's. I would have believed that this would show up any major weaknesses in materials yet the most common frame material used for this event is carbon.

Spot on. though I would say rather then most common frame material used, it is the only frame material used. Unless someone knows better.

 

[raindog]

Spot on. though I would say rather then most common frame material used, it is the only frame material used. Unless someone knows better.

Aluminium frames are still used sometimes
http://www.cyclingnews.com/features/photos/start-line-tech-gallery-from-paris-roubaix/217206
I remember about three years ago, Boonen had a special aluminium frame built because of back pains he was getting. Can't remember his team's bike supplier at the time though.