How long does a carbon frame last?

[Foss62]

Most people agree that a steel frame is forever - as long as it receives a reasonable level of care. Aluminium frames do have a finite lifespan (unfortunately around ten years in the case of my lovely Dyna-Tech Tourlite, which was partially aluminium).
However I have seen a few comments suggesting that you should not expect a carbon fibre frame to last very long - slightly worrying as mine is now eight years old.
I have carbon fibre fishing rods that are more than 30 years old and still fine - and would expect that they undergo much more flexing than a bike frame ever would - so is there any truth in the stories about carbon’s lack of robustness for bikes?
Does anyone have a very old carbon frame still in regular use (I guess the very oldest could be about 30 years)?

[Robertb]

Take a look at some of the videos of frames being tested to destruction. It’s astonishing what they put up with. It’s hard to imagine they’d wear out or fatigue in normal use.

CF frames can be repaired too, though its specialist work and not cheap.

[v8notbrave]

??? My last steelie due to winter use and neglect got very rusty at the drop outs, so I found an old Aluminium frame on eBay and switched it out

So now I have 2 * 20 yr old aluminium frames and they're good as new, who said they are finite lifespan? (They have lovely shiny stainless steel drop outs)

Surely carbon is how it's maintained and the quality, cheap could theoretically delaminate with winter cold and salt but if you look after it then it should last for yonks (unless you crash it)

What's more important is the ride you want (comfort, weight etc) and the geo you want

(To add I have a 2008 TT carbon bike that's been lovingly looked after and the frame is as new)

[SkinnyPete]

v8notbrave said:

??? My last steelie due to winter use and neglect got very rusty at the drop outs, so I found an old Aluminium frame on eBay and switched it out

So now I have 2 * 20 yr old aluminium frames and they're good as new, who said they are finite lifespan? (They have lovely shiny stainless steel drop outs)

Surely carbon is how it's maintained and the quality, cheap could theoretically delaminate with winter cold and salt but if you look after it then it should last for yonks (unless you crash it)

What's more important is the ride you want (comfort, weight etc) and the geo you want

(To add I have a 2008 TT carbon bike that's been lovingly looked after and the frame is as new)

The manual for both my aluminium bikes say the frame life is finite.

[Gary C]

Trouble with CF is its related to stress and UV.

UV 'should' be limited by inhibitors in the gel (but best not to store it in sunlight), so the real limit is impacts and stresses. They build until it goes bang and fail.

and that's unquantifiable unfortunately

[Liamjrhodes]

All materials have a fatigue life and most manufacturers will have to put a very conservative lifespan on it to cover them selves if the worst does happen. But unless you are regularly stressing your frame close to its limit I doubt regular usage will cause enough to make it fail due to age. There are plenty of people riding round on old bike frames

[RustyNissanPrairie]

In terms of fatigue
Longest life - shortest life

CF
Steel
Aluminium

Failure mode
Catastrophic - non catastrophic
Steel
Aluminium
CF

My preference has always been steel frames for their ride quality. Aluminium depends on the design as to how it rides, same with CF. I have cracked a few aluminium frames back in the day (ex BMXer, downhiller, enduro)

[v8notbrave]

SkinnyPete said:

The manual for both my aluminium bikes say the frame life is finite.

Pete that's cover my ass US legislation, still mint after 2 decades here