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My BMC team road frame and fork have covered 35000km. No accidents or issues to report, at 7kgs on the button thus bike is superb.

 

Two groupsets and two wheelset later, I have no issue lining up to race the bike.

 

I have to ask, at what point do i need to worry about the carbon failing?

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Alu has the shortest fatigue life of all the frame materials. Carbon's is infinitely longer. 

id say if you haven't had a crash or drop or man handeling it should probably last a lifetime (like steel)

 

one thing you do however need to take a look at ever so often is where the headset bearings/crown races pair with a carbon fork's steerer tube (if the steerer is also carbon). Worn bearings or the slightest play due to a loose plug or whatever will have those cutting a nice little path/rail into the steerer over time....essentially turning your headset into a pipe cutter for carbon....and then one day you'll hit a little dip in the road and realise you are holding your bars in your hands and they are not connected to your frame anymore lol   

 

If it puts you more at easy.....i have a beefy trail carbon fork on my MTB and hit 1m drops and other obstacles on it often and i still have my teeth. 

Edited by morneS555
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Wrt structural fatigue, in theory:

 

A a quality aluminium frame should last a lifetime. The same aluminium is used on airctaft that fly almost every day fot 30 years.

 

Streel and titanium frames should last two lifetimes.

 

A carbon frame should last the liftime of your children's children. The fibre never fatigues. The matrix material (epoxy in this case) does, but slower than any metal.

 

Ride it till it wears you out.

 

(What defines a quality frame is a different debate)

Edited by Christie
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FWIW, Trek claim their OCLV (LV = low void) frames exceed aerospace specs iro voids (iow probably sub-1%)*. That should in theory make them extremely durable. Other manufacturers I don't know about.

 

 

* They also provide a lifetime warranty on OCLV frames for the original purchaser. They say that their original OCLV frames still carry a full replacement warranty some 40 years later. A bit of marketing there but still....

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OCLV for optimum compaction low void isn't different from the way other frames are moulded. The only real stand out is TIME Sport of France. Their Resin Transfer Moulding is a patented technique and seems to produce void free frames more consistently than others...

 

But.. Stuff happens and voids happen but the owner of the bike won't know

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Dunno.

 

Some of the data out there seems to indicate that Trek pioneered *some* of the techniques. Don't think anyone else specifically claims low void and one would think they would? I guess it all depends upon the facility oversight/QA in Taiwan where most of these things are made anyway. I think KTM actually make their own frames?

 

But the Trek "forever" warranty is *somewhat* reassuring.

 

Personally, I'm inclined to think the design is likely to become totally obsolete before the materials reach their limit.

 

That said, I have seen a carbon chain stay failure occurring unexpectedly on a pretty new carbon bike. Was a bit of a close call. I guess possibly a void issue then.

Edited by MudLark
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Dunno.

 

Some of the data out there seems to indicate that Trek pioneered *some* of the techniques. Don't think anyone else specifically claims low void and one would think they would? I guess it all depends upon the facility oversight/QA in Taiwan where most of these things are made anyway. I think KTM actually make their own frames?

 

But the Trek "forever" warranty is *somewhat* reassuring.

 

Personally, I'm inclined to think the design is likely to become totally obsolete before the materials reach their limit.

 

That said, I have seen a carbon chain stay failure occurring unexpectedly on a pretty new carbon bike. Was a bit of a close call. I guess possibly a void issue then.

 

 

 

TREK did pioneer the technique used by most manufacturers today. Back when they engineered OCLV there was basically two ways to make a carbon frame.

Take carbon tubes and glue them into either carbon, or metal lugs. This allowed lots of differenct sizes and low voids because the tubes were moulded separately from the lugs. Making the lugs became the problem. If metal lugs were used then electrically isolating the carbon from the metal lug was the challenge, mostly overcome by using glassfibre between the carbon tube and metal lug.

TREK then came up with a technique that was being used in the construction of Formula 1 cars were parts of the chassis were made from prepreg Carbon sheets, moulded and semi cured, joiined and co-cured to form one structure.

TREK's version took semi cured carbon lugs with a male joiner  and inserted that part into a semi cured tubed. The frame was assembled this way and then the whole thing went into a modular mould and final cured.

Most carbon frames are produced this way today.

 

 

The issue of warranty does give peace of mind but its not an indicator of superior manufacture.

Each carbon frame is actually unique because its a hand layup. Technicians conducting the layup of prepreg sheet don't reproduce align of each sheet exactly for every frame.

The use of Prepreg does make managing voids much easier but they still get it wrong day to day. Just watch Leuscher Technic on Youtube.

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