17 year old carbon frame - too old to ride?

[Bonefishblues]

Similarly carbon fibre fly rods seem to resist breakage pretty well (until the fool on the end tries to bend it in a plane it wasn't designed to bend in!)

[Brucey]

People on this forum get all silly about carbon fibre, largely because it's a relatively new material in cycle frames. I sail against boats with 20-30 year old carbon masts, these have huge loads placed on them - even a 14' dinghy can have a tonne of compression load on the mast when sailed at full chat. They are fine unless suffering impact damage. Every 10 years or so they get stripped and re-varnished, but then they stay outdoors all the time.
Nobody feels unsafe flying on an A320 Airbus, even though they have large carbon fibre sections on the wings. The oldest ones are now around 35 years old.

CF masts are both rather over-engineered for the loads that they typically see and probably won't kill you if they do break.

Airbus CF parts are well-coated, regularly inspected and are arguably designed for a certain stiffness over and above a certain strength per se.

In both cases comparisons are only valid if the resin and fibre systems are the same as well as the bonding to other sections.

Perhaps the only thing that is 'silly' is to assume that these things are always the same for any CF structure.

cheers

[hamster]

Of course I'm not saying these things are identical. However people on these forums take carbon fibre as a novel material, when there is in fact decades of experience in design of structures and (more relevantly) of material development. Material vendors have considerable knowledge and recommend customised solutions for different structures and applications.

Delamination and degradation over decades isn't a problem even on structures (like marine) which spend all year outdoors, yet suddenly there is lots of concern about UV degradation on bikes that get a few hours weekly out in the sunshine. It's irrational.

Having cut away the rig of a yacht after a mast collapse at 3am mid-channel - in the middle of the ship traffic zone, I can assure you it was very much a life-threatening situation.

[mig]

i don't doubt that manufacturers have good knowledge of the fabrics. my concern in this instance would be how they would have specced a frame back in 2001?

would it be viewed to be made as light as possible and to last three weeks in a grand tour then that's it? anything more is a bonus etc ie purely a racing frame.

or made to be used everyday / more extensively / more cycles of twist and bend / over more than a decade as a mode of transport?

given their knowledge of materials they wouldn't come up with the same result to do both jobs surely.

what were the warranties like in this era?

[Brucey]

the materials being used (and the manufacturing methods) are being changed all the time, and have anyway always varied with the application. A lot of bike stuff is made very cheaply and to compare it with aircraft parts and assume it might behave similarly would usually be quite wrong. UV degradation is only one thing to worry about; there are many other mechanisms by which the composite itself or the joints might degrade.

To use an analogy, to assume that 'all CF is the same' is as big or bigger mistake than to assume that 'all wood is the same'.

Given that new CF forks are often not perfectly reliable, and try their best to kill people, I don't think it is even slightly irrational to be concerned about possible degradation in ones that are a couple of decades old.

There is also the question of acceptable risk; what is acceptable? I don't think it is good enough to be right most of the time, or even 99 times out of 100 in this sort of application, and anyway it is a matter of personal choice; you might feel happy if it is one time in 10000 that you might be wrong but this might be different for other folk.

cheers

[Brucey]

Having cut away the rig of a yacht after a mast collapse at 3am mid-channel - in the middle of the ship traffic zone, I can assure you it was very much a life-threatening situation.

This situation is comparable (very similar in fact) to a failure in the main frame as you are riding; normally when this happens you can bring the bike to a halt (because the structure has some redundancy) and the main danger is from other traffic.

A fork breakage is quite a different matter; a comparable situation in sailing could be that the boat sinks (instantly), you don't have a life jacket, and there are sharks etc....

cheers

[hamster]

Having cut away the rig of a yacht after a mast collapse at 3am mid-channel - in the middle of the ship traffic zone, I can assure you it was very much a life-threatening situation.

This situation is comparable (very similar in fact) to a failure in the main frame as you are riding; normally when this happens you can bring the bike to a halt (because the structure has some redundancy) and the main danger is from other traffic.

It's hard to compare accident consequences. Anyone on the leeward side could have had 15m of rig fall on him at the moment of collapse, which would not have been great fun. In this case it was a lumpy F7 with big rolling waves and the danger was far more urgent than being run down - the broken rig was bashing up against the hull and would punch through in short order. Out with the bolt cutters, chop and pitch the lot away to Davy Jones' asap. Only then would it be possible to start the engine, otherwise we would have added a fouled prop to our troubles. Bye bye £35,000 of rig - in 1980s money. A lifejacket is of marginal use longer term (allows you to survive initial cold shock) as hypothermia will get you within an hour or so.

The boat was a kevlar/foam prototype, built early 1981. She is still racing competitively today.

[De Sisti]

Is there any chance that the OP will put the bike up for sale on this forum (if he/she still has any doubts)?

[s1965c]

Why not replace the fork with one from another bike for a while? That's the part with the biggest risk attached.

If the rest of the frame holds up and passes your regular checks, you can buy a new carbon fork for the bike.

[mercalia]

well the op has had his moneys worth. why risk it?

[1942alexander]

well the op has had his moneys worth. why risk it?

Has it really now come down to this? I repair and restore 60 to 70 year old bikes, all of them still capable of being ridden. If this attitude is the norm today there will be nothing which can be termed a "classic" available for future generations to admire and covet as we do with almost any other vintage item.

[Brucey]

well the op has had his moneys worth. why risk it?

Has it really now come down to this? I repair and restore 60 to 70 year old bikes, all of them still capable of being ridden. If this attitude is the norm today there will be nothing which can be termed a "classic" available for future generations to admire and covet as we do with almost any other vintage item.

yeah, well that is a problem with plastic, and plastic bikes are no exception. Probably there will just be a nasty archaeological layer which is comprised of various forms of plastic tat, bikes included.

Douglas Adams thought that society might collapse into a morass of shoe shops selling ever-more short-lived shoes, but it could just turn out to be bicycles instead.....

cheers

[mercalia]

well the op has had his moneys worth. why risk it?

Has it really now come down to this? I repair and restore 60 to 70 year old bikes, all of them still capable of being ridden. If this attitude is the norm today there will be nothing which can be termed a "classic" available for future generations to admire and covet as we do with almost any other vintage item.

hmm have a go at this one then?

https://www.ebay.co.uk/itm/VERY-RARE-RALEIGH-LENTON-CLUBMAN-1949-ROAD-BIKE-REYNOLDS-531/263540990099?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

well my dawes 1-down in steel is still in fine condition I have no worries about will out last me barring accidents

[1942alexander]

hmm have a go at this one then?

https://www.ebay.co.uk/itm/VERY-RARE-RALEIGH-LENTON-CLUBMAN-1949-ROAD-BIKE-REYNOLDS-531/263540990099?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

well my dawes 1-down in steel is still in fine condition I have no worries about will out last me barring accidents

Well it certainly old enough and it might be rare but it's not the type of frame I go after.

This is the quality I'm interested in.

Cheers... Alex

[pliptrot]

A lot of bike stuff is made very cheaply and to compare it with aircraft parts and assume it might behave similarly would usually be quite wrong. UV degradation is only one thing to worry about; there are many other mechanisms by which the composite itself or the joints might degrade.

To use an analogy, to assume that 'all CF is the same' is as big or bigger mistake than to assume that 'all wood is the same'.

And goodness knows it is difficult to get any objective information about what is on offer. I have long suspected that the cheap Chinese frame on ebay is not much different to one selling for 10 times as much from one of the big, well-known (predominantly American) manufacturers (or suppliers - they don't manufacture most of this stuff themselves). But how do you know? For the longest time weight was the obsession (we are now hearing that aerodynamics trump this) and you can buy a very light frame on ebay for the same money as a second hand 531 frame. Why not? Why?