Carbon Fiber Fork Failer

That's one thing I've never understood: Carbon is great in some places but aluminum is still lighter and a minor scratch is not of huge concern. I'll never say never, but I'd never buy a bike with a carbon steer tube on the fork, or for that matter, carbon cranks (yes, I know they're better, but I'm stubborn).

I'd have someone else take a look at the fork. It depends on the length and depth of the problem, amongst other things.

Reynoldsouzopro said:

I am new to this site so here goes:🙂

Does anyone know how Carbon forks have failed? (of any brand)
Do they fail at the forks?, at the Crown? or at the top of the steer tube ?where the stem attaches to the steerer??
Do they ever fail in the area between the bearings?, (within the head tub of the frame).
Are failures more a result of crashes? and/ or wrong installation of stems and use of star nuts??
I have a Reynolds ouzo pro fork that was mounted on a used colnago Master light.
I put 900 plus miles on it when I decided to change the stem. I was shocked :eek: to find that it had been mounted with a star nut that kind of damaged the carbon fiber steer tube going an inch down from the top.😠
I have already installed an aluminum sleave in the steer tube with JB weld steel epoxy.
I am debating whether or not it is safer now.😕 ,(albeit I would have never known the fork steer tube was damaged had I not changed the stem and would have been really [censored] as I was flying thru the air and tumbling on the ground changing from a man to a quivering mass of flesh if it would have broken.🙄 )

Believe a CF fork could fail most anywhere. I've only heard of one here locally that was cracked in a crash; about a one inch vertical crack in an outside lower leg. It was still rideable, but was replaced after a composite engineer checked it out and advised that it was "compromised".

You probably know that the Reynolds Ouzo Pro manual states that the compression plug provided with the fork must be installed to maintain structural integrity, and that use of a substitute part may result in bad things happening. That's likely because without the plug, the tube could be crushed by the stem and weakened. The gouges you have inside from the star nut would make this potential more likely.

Believe an engineer would tell you your home repair depends on the compatibility of JB Weld with the fork tube, as well as the fit and length of the al sleeve. If the sleeve was tight enough to burr or notch the id of the tube going in, or if the sleeve ends right at the bottom of the stem, I'd think that would cause a stress concentration right where you don't want it to be.

I say you're definately an experiment of one here. The thing may hold up a long time, or maybe not. Could depend on how strong a rider you are, and how much you come out of the saddle to sprint or hammer up a steep hills. Personally, I'd ride it carefully now and put a new Ouzo Pro fork on order.

ganderctr said:

I'll never say never, but I'd never buy a bike with a carbon steer tube on the fork,......

But CF fork legs or a CF frame is OK?? LOL

Believe an engineer would tell you your home repair depends on the compatibility of JB Weld with the fork tube, as well as the fit and length of the al sleeve. If the sleeve was tight enough to burr or notch the id of the tube going in, or if the sleeve ends right at the bottom of the stem, I'd think that would cause a stress concentration right where you don't want it to be.

I say you're definately an experiment of one here. The thing may hold up a long time, or maybe not. Could depend on how strong a rider you are, and how much you come out of the saddle to sprint or hammer up a steep hills. Personally, I'd ride it carefully now and put a new Ouzo Pro fork on order.[/QUOTE]Thanks for the reply...and so quickly.
The above is exactly my concern with the repair. the question I would really like answered is where other forks have actually failed.
I have already come to the same conclusion as you. Ride with caution and check it soon...... And put a new one on order.

There's a few "feats of strength" amongst the reviews on Road Bike Review

"Summary:
Wow what a fork. 5 days after I had purchased my bike, a motorist in a Chrysler Imperial didn't see me coming and pulled out. I had about 8ft to react, needless to say I ended up "T-Boning" him in the driver side front quarter panel. I was going about 18mph at the time of the accident. My front wheel was destroyed; the fork: unscathed minus a few scratches. The guys at the bike shop couldn't belive it, neither could I. All in all, smooths out the road like glass and is one tough fork.

Strengths:
Strength, Strength, Strength"

"Summary:
..... It's tough enough- It just survived a 25/30 mp/h head-on; I didn't fair so well. My only concern is unseen cracks, but that's a risk with any Carbon fork. If you want a top-notch fork that can go tete-de-tete with the best, you got it here."

http://www.roadbikereview.com/Forks/Reynolds/PRD_50025_2492crx.aspx

ganderctr said:

...aluminum is still lighter and a minor scratch is not of huge concern...

I beg to differ! A minor scratch on a bit of aluminium can turn into a crack, depending how it is loaded, and you're unlikely to notice until it breaks, possibly uniting you with the road at 30mph. Ever seen someone cut a ceramic tile? They just score it with a diamond-tipped cutter and then break it in two by hand.

I saw this scary website (can't remember where it is unfortunately) about bike accidents which had been caused by scratched components. One of the examples was a crank arm which had broken clean in two because there was a small scratch on it, which developed into a crack, and then it was only a matter of time. If a scratch can do that to a crank arm, imagine what can happen to a thin-walled, lightweight alu handlebar. That's why I was [censored] to find that whoever made my bike trimmed the bar tape with a knife, scratching the tubing all the way round. 😠

Fat Hack said:

There's a few "feats of strength" amongst the reviews on Road Bike Review

"Summary:
Wow what a fork. 5 days after I had purchased my bike, a motorist in a Chrysler Imperial didn't see me coming and pulled out. I had about 8ft to react, needless to say I ended up "T-Boning" him in the driver side front quarter panel. I was going about 18mph at the time of the accident. My front wheel was destroyed; the fork: unscathed minus a few scratches. The guys at the bike shop couldn't belive it, neither could I. All in all, smooths out the road like glass and is one tough fork.

Strengths:
Strength, Strength, Strength"

"Summary:
..... It's tough enough- It just survived a 25/30 mp/h head-on; I didn't fair so well. My only concern is unseen cracks, but that's a risk with any Carbon fork. If you want a top-notch fork that can go tete-de-tete with the best, you got it here."

roadbikereview.comPRD 50025 2492crx.aspxOpen ↗

It seems as though the replies That are accumulating are taking a different turn then what I originally asked.
Just to let everyone know, I am not knocking Carbon fiber forks in general, I am not knocking Reynolds forks at all. I like the fork. I am just trying to get more information regarding where exactly have carbon fiber forks, ANY brand fork, failed...IF in fact they have failed at all, without a crash that had damaged them.
The problem I have with my fork is that it was installed wrong, according to the installation instructions.
anyway thanks for the info so far I appreciate it.

mjw_byrne said:

I beg to differ! A minor scratch on a bit of aluminium can turn into a crack, depending how it is loaded, and you're unlikely to notice until it breaks, possibly uniting you with the road at 30mph. Ever seen someone cut a ceramic tile? They just score it with a diamond-tipped cutter and then break it in two by hand.

I have to agree. I have read (in a few different sources) of how scratches on aluminum frames can easily turn into cracks. If you have a scratch on your Al frame you should check it frequently to be sure it has not become a crack. This is not a problem with steel. However, if a steel frame is scratched it should be covered with touch up paint to prevent it from rusting. I am not sure about carbon, but I would definitely be concerned about any major scratches. Carbon can fail anywhere, and a lot has to do with manufacture quality. You are safer going with major brand names such as Reynolds or Easton over the low cost alternatives such as Weyless or Forte. However, once a part is cracked all bets are off regardless of manufacture quality.

Reynoldsouzopro said:

The problem I have with my fork is that it was installed wrong, according to the installation instructions.
anyway thanks for the info so far I appreciate it.

Those are the manufacturer instructions for a reason. Deep scratches in the surface of a composite material lead to cracks through the matrix material. You might not even see the cracks growing until the whole thing delaminates. JB Weld is pretty good for steel, but it isn't meant to bond to aluminum or carbon. The best thing you can probably do right now is get in touch with Reynolds and see if they can cut out the steerer and bond in a new one. That's probably going to be a lot cheaper than buying a new fork or having your face put back together when you rip the top of the steerer off in a sprint.

artmichalek said:

The best thing you can probably do right now is get in touch with Reynolds and see if they can cut out the steerer and bond in a new one. That's probably going to be a lot cheaper than buying a new fork or having your face put back together when you rip the top of the steerer off in a sprint.

They would not touch that one with a 10 foot steerer tube.

Reynoldsouzopro said:

It seems as though the replies That are accumulating are taking a different turn then what I originally asked.
Just to let everyone know, I am not knocking Carbon fiber forks in general, I am not knocking Reynolds forks at all. I like the fork. I am just trying to get more information regarding where exactly have carbon fiber forks, ANY brand fork, failed...IF in fact they have failed at all, without a crash that had damaged them.
The problem I have with my fork is that it was installed wrong, according to the installation instructions.
anyway thanks for the info so far I appreciate it.

You are asking people that don't have a clue and ae getting nothing but BS and nonsense.

boudreaux said:

You are asking people that don't have a clue and ae getting nothing but BS and nonsense.

Well I look at it as people are trying to help in anyway they can. I know what is good advice and good information, however I wasn't really looking for advice in this instance.
Anyway I will drop this subject as I have decided to get a new reynolds ouzo pro fork and install it myself so that I can insure proper installation.
Thanks everyone again for their opinions🙂

You could sell it on Ebay while noting that the fork would be useful if it would have enough steering tube left over after it was cut down to remove the damaged areas. The fork would probably be okay then.

mjw_byrne said:

I beg to differ! A minor scratch on a bit of aluminium can turn into a crack, depending how it is loaded, and you're unlikely to notice until it breaks, possibly uniting you with the road at 30mph. Ever seen someone cut a ceramic tile? They just score it with a diamond-tipped cutter and then break it in two by hand.

I saw this scary website (can't remember where it is unfortunately) about bike accidents which had been caused by scratched components. One of the examples was a crank arm which had broken clean in two because there was a small scratch on it, which developed into a crack, and then it was only a matter of time. If a scratch can do that to a crank arm, imagine what can happen to a thin-walled, lightweight alu handlebar. That's why I was [censored] to find that whoever made my bike trimmed the bar tape with a knife, scratching the tubing all the way round. 😠

I think that aluminum is quite a bit more ductile that a ceramic tile and would bend quite a bit before it actually fractured if at all. Done lots of tiling....
A scratch would be a stress riser depending on the depth of the scratch and the loads applied and the actual type of aluminum. Not nessessarily fatal but you do have a point.