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likebikes
03-21-2016, 01:09 PM
what would cause such a clean, straight failure?

lug creating a stress riser? too much heat during initial brazing? night gremlins with a hacksaw?

https://scontent-ord1-1.xx.fbcdn.net/hphotos-xat1/v/t1.0-9/971428_10205571930449073_3994567895055767215_n.jpg ?oh=044432a7372b4326ef070196f8dac2c7&oe=574C26ED

AngryScientist
03-21-2016, 01:21 PM
tell us more about the circumstances under which you found this crack. How old is it? That is troublesome!

54ny77
03-21-2016, 01:27 PM
don't park your bike near an amateur sushi chef.

FlashUNC
03-21-2016, 01:31 PM
A photo would do wonders.

AngryScientist
03-21-2016, 01:31 PM
A photo would do wonders.

huh?

FlashUNC
03-21-2016, 01:34 PM
huh?

Not seeing a photo attached to the post. I'm guessing I've been Net Nanny'd?

AngryScientist
03-21-2016, 01:36 PM
Not seeing a photo attached to the post. I'm guessing I've been Net Nanny'd?

yes. it's pretty ugly.

LegendRider
03-21-2016, 01:41 PM
Do you have any enemies?

Lewis Moon
03-21-2016, 01:43 PM
That's just freaky. I had a downtube that went on an old lugged Skunkhumper, and the break looked a lot more "worked" than that, ie: the edges were turned and a bit jagged. That looks almost like there was a seam there. Very troubling indeed. Paging Mr Sachs.

fuzzalow
03-21-2016, 01:44 PM
Is this your bike & your fork? I hope it is and not because I wish misfortune befall you but rather that what happened here is something you can know and talk about.

If this is just a random photo scarfed off the web, then I'd say it is posted as inflammatory and is unfair - because you can find pictures of almost anything on the web. And with these random pictures there is no way to know what truly happened beforehand to make this failure.

I may have my differences with Mr. Sachs, but I will neither stoop to his level nor will I not speak out when somebody, even he, looks to be getting a cheap shot.

Tell me this is your bike and you can describe what and how you owned this and what you did that led to this failure. Then we can go from there.

sjauch2
03-21-2016, 01:45 PM
My guess is you won't get any info out of the original poster. I believe this photo was found on another forum and posted here.

ColonelJLloyd
03-21-2016, 01:46 PM
Doesn't seem like something that would come from riding*.

*by someone who is not Martyn Ashton or Danny MacAskill

Edit: Oh, well if that's it's in pretty bad taste without a disclaimer or background, additional info, etc.

FlashUNC
03-21-2016, 01:56 PM
Now that I am Net Nanny free...ye Gods.

That's no bueno.

gdw
03-21-2016, 02:03 PM
Never let the kids play with your Sawzall.....

e-RICHIE
03-21-2016, 02:11 PM
If you put my name in the header to get my attention, you have. Email me with the facts, a name, a date of purchase, a serial number, etc and I'll deal with you directly. Thanks.

shovelhd
03-21-2016, 02:13 PM
If you put my name in the header to get my attention, you have. Email me with the facts, a name, a date of purchase, a serial number, etc and I'll deal with you directly. Thanks.

Please let us know if the OP has a real issue with his bike or if he's just trolling.

gone
03-21-2016, 02:16 PM
If this is just a random photo scarfed off the web, then I'd say it is posted as inflammatory and is unfair - because you can find pictures of almost anything on the web. And with these random pictures there is no way to know what truly happened beforehand to make this failure.

And this is exactly what happened, I know this for a fact because I know the owner.

And I agree with you that it's inflammatory and unfair. If the owner wished to have it posted here, (and yes, he's a member) he'd have done so.

Black Dog
03-21-2016, 02:18 PM
Before we light the torches and grab the pitchforks we might want to consider that the OP was just asking a technical question about what could cause such a failure, nothing more and nothing less. We simply don't know until we know.

ergott
03-21-2016, 02:23 PM
I though this was funny. I searched via google for the image and this was the result.

https://ergottwheels.smugmug.com/Cycling/Cycling-shots/i-k8VSSxj/0/XL/fork%20extinguisher-XL.jpg

tumbler
03-21-2016, 02:24 PM
tell us more about the circumstances under which you found this crack. How old is it? That is troublesome!

Yikes. I'm also curious when and how you noticed this. Any accidents on the bike previously that could have started the crack and gone unnoticed?

Edit: Why are we jumping to the conclusion that the OP was trolling? A quick search of his posts didn't suggest a particular hatred for RS. Sure, he could be trolling, or he could be using a bike forum to ask a bike question. Maybe proper etiquette would be to leave out the builder's name, but anyone with half a brain would have known the builder the second they saw the image. Would anyone be upset with the post if it were titled "Cracked Bianchi Fork" and included the same question?

William
03-21-2016, 02:27 PM
I though this was funny. I searched via google for the image and this was the result.

https://ergottwheels.smugmug.com/Cycling/Cycling-shots/i-k8VSSxj/0/XL/fork%20extinguisher-XL.jpg


Bespoke fire extinguishers?!?!?:confused:


;);) :)






William

William
03-21-2016, 02:33 PM
what would cause such a clean, straight failure?

lug creating a stress riser? too much heat during initial brazing? night gremlins with a hacksaw?




Is this your bike?

If it's not, any multitude of things could have caused something like that to any bike. No way of knowing for sure, which would lead me to ask: Why are you asking?








William

that guy
03-21-2016, 02:49 PM
I thought this was a bike forum where people were supposed to ask questions?

dsillito
03-21-2016, 03:03 PM
I'm not going to wade into any discussion about this fork or image in particular.

But...

It did get me wondering...are there generally more expansion forces on the front, or the rear of a fork blade at that location? Or are they designed for the force to be travelling straight up the steerer tube at that point?

I would be less surprised to see such a crack on the font of the blade, as the braking force on the front wheel would be bending the fork backwards.

Tells ya what I'm gonna do. I'll make a hacksaw nick on the fronts and backs of my fork blades, call it a "scientific experiment", and report back. Or instruct my next of kin to do so in my will.

eviction party
03-21-2016, 04:06 PM
Is this your bike?

If it's not, any multitude of things could have caused something like that to any bike. No way of knowing for sure, which would lead me to ask: Why are you asking?

Why wouldn't you ask?

Chief
03-21-2016, 04:35 PM
I would be less surprised to see such a crack on the font of the blade, as the braking force on the front wheel would be bending the fork backwards.


However if the bike was on a moving roof rack and it hit an obstruction, this is the type of failure one might see. Pure conjecture. :confused:

OtayBW
03-21-2016, 04:38 PM
I may have my differences with Mr. Sachs, but I will neither stoop to his level nor will I not speak out when somebody, even he, looks to be getting a cheap shot.Fuzz, I gotta hand it to you: you are the master of the 'left-handed ~compliment'! :hello:

beeatnik
03-21-2016, 04:48 PM
My reading comprehension must be dichotomous as I'm able to parse through Fuzzalow's arcane, dense text and yet it appears I've been misreading Mr. Sach's musings. In the thousands of lines, I've read online or in print, I've never seen him waste a word with a cheap shot.

tuscanyswe
03-21-2016, 04:55 PM
I thought this was a bike forum where people were supposed to ask questions?

+1

Way way protective comments imo.

livingminimal
03-21-2016, 05:04 PM
My reading comprehension must be dichotomous as I'm able to parse through Fuzzalow's arcane, dense text and yet it appears I've been misreading Mr. Sach's musings. In the thousands of lines, I've read online or in print, I've never seen him waste a word with a cheap shot.

Exactly. meanwhile many of his detractors carry earth-shattering levels of self-righteous indignation.

I mean, when you imply someone has a level you're not going to stoop to...you just did.

Mark McM
03-21-2016, 05:08 PM
It did get me wondering...are there generally more expansion forces on the front, or the rear of a fork blade at that location? Or are they designed for the force to be travelling straight up the steerer tube at that point?

I would be less surprised to see such a crack on the font of the blade, as the braking force on the front wheel would be bending the fork backwards.

Braking does tend to want to bend the fork backward (front of blades under tension), while vertical load bearing forces tend to want to bend the fork forward (rear of bladed under tension). Cracks form from fatigue, which are not the result of a single excessive force, but from fatigue, which is the result of many, many, load cycles. Since a fork spends more time under vertical loads, and experiences a load cycle for every bump we hit, so fork blade cracks are most common on the back of the blades.

I had a fork develop a fatigue crack in a similar location. The crack was just as straight as in the photo, and nearly as clean. The fork used an internal crown, and the crack occurred just at the bottom edge of the joint between the crown and the blade.

weisan
03-21-2016, 05:25 PM
Like pal, come back! We still like you...you know that, right?

Everyone take a deep breath....it's only Monday.

http://www.psychicgurus.org/wp-content/uploads/2014/11/relax-600x300.jpg

SPOKE
03-21-2016, 05:32 PM
Me thinks the crack could be from too many bunny hops or wheelies with hard landings😳😱

unterhausen
03-21-2016, 05:39 PM
a fatigue crack on a steel fork will grow in a very straight line -- at least after it gets to a certain length. That's a really long crack and has taken a lot of riding to get to that length. There would be necking if it was related to jumping off of walls or something like that. That's why my motto is "clean your bike"

cinema
03-21-2016, 05:45 PM
oy gevalt

Peter P.
03-21-2016, 05:51 PM
I think there's too much drama with this thread. Stuff happens, even to the finest of builders.

It IS interesting that the crack is so straight. I've cracked a lot of frames and still couldn't do that good of a job! ;)

I had a fork fail from fatigue. It cracked at the base of the fork crown race, at the back, and slowly propagated toward the front, just like that fork blade. Clearly, that fork blade crack was due to long term stress because there's no buckling of the of the blade near the crack.

What's also interesting is the unpainted edge of the crack is clean and shiny. It shows no signs of rust or oxidation which means the crack must have developed pretty quickly, no?

I hope we'll hear of a resolution.

unterhausen
03-21-2016, 06:01 PM
the resolution to this is none of our business. I feel guilty for even commenting on this thread, but fatigue cracks are one of my research interests. It doesn't look shiny to me, and there is no reason to expect rust, although I think I see rust at the widest part of the blade (minor axis). I imagine there crack took a more circuitous path on the back, where I assume the initiation point is. Crack was growing very fast by the time it was discovered.

fuzzalow
03-21-2016, 06:08 PM
I hope we'll hear of a resolution.

No we will not. There is nothing to resolve. This was a childish attempt at instigating a schoolyard brawl.

Instead of a rallying point of, say, a Silca pump to enlist and stoke a populist rant; a Sachs broken fork was waving a red flag at opposing camps to engage in battle. Who's gonna fight this battle? The self-righteous indignants versus the swooning sychophants?

HaHa, not me. Not worth a seconds thought.

eBAUMANN
03-21-2016, 06:17 PM
Braking does tend to want to bend the fork backward (front of blades under tension), while vertical load bearing forces tend to want to bend the fork forward (rear of bladed under tension). Cracks form from fatigue, which are not the result of a single excessive force, but from fatigue, which is the result of many, many, load cycles. Since a fork spends more time under vertical loads, and experiences a load cycle for every bump we hit, so fork blade cracks are most common on the back of the blades.

I had a fork develop a fatigue crack in a similar location. The crack was just as straight as in the photo, and nearly as clean. The fork used an internal crown, and the crack occurred just at the bottom edge of the joint between the crown and the blade.

This is actually a great explanation of what is seen in that photo, thanks for taking the time to lay it out for us. :beer:

BumbleBeeDave
03-21-2016, 06:30 PM
Imperfection is perfection.

BBD

Cicli
03-21-2016, 07:02 PM
Imperfection is perfection.

BBD

In Yurope.

sjbraun
03-21-2016, 07:15 PM
"This was a childish attempt at instigating a schoolyard brawl."

Is it not possible for you to see this as a simple question, and no more?

There isn't a troll behind every question. No need to slam someone just because you don't have an answer.

Unless you were going for sarcastic humor, in which case, proceed

Kirk007
03-21-2016, 07:30 PM
No we will not. There is nothing to resolve. This was a childish attempt at instigating a schoolyard brawl.

Instead of a rallying point of, say, a Silca pump to enlist and stoke a populist rant; a Sachs broken fork was waving a red flag at opposing camps to engage in battle. Who's gonna fight this battle? The self-righteous indignants versus the swooning sychophants?

HaHa, not me. Not worth a seconds thought.

Yet you posted, insulting both the original poster (in both posts) and Mr. Sachs. Perhaps you know the OP such that you can infer a nefarious intent or perhaps his post was just a post and you decided to stir the pot for your own amusement.

4Rings6Stars
03-21-2016, 07:45 PM
"This was a childish attempt at instigating a schoolyard brawl."

Is it not possible for you to see this as a simple question, and no more?

There isn't a troll behind every question. No need to slam someone just because you don't have an answer.

Unless you were going for sarcastic humor, in which case, proceed

Maybe not, but from what I've gathered over the years the OP has been guilty of trolling quite a few times...

eviction party
03-21-2016, 08:13 PM
If you listen closely to a bicycle, sometimes you can hear the voice of the tubes. And, sometimes, when it's especially quiet and you pay especially close attention, you can make out what it's saying.

http://i.imgur.com/BbtAOd1.jpg

titans
03-21-2016, 08:41 PM
Something odd around the crack when you enlarge the pic?

Cat3roadracer
03-21-2016, 08:59 PM
Like touch up paint?

rustychisel
03-21-2016, 09:29 PM
Ph**k the fork.

I'm enjoying the internecine warfare which comes with the subtler points of forum etiquette. Fascinating (but ultimately not very rewarding). Just my 0.02c

cinema
03-21-2016, 09:37 PM
it just looks like compression. very low quality pic. interested in the story as well unless trolling. am i missing something? something going on across the hall?

sandyrs
03-21-2016, 10:00 PM
Ph**k the fork.

I'm enjoying the internecine warfare which comes with the subtler points of forum etiquette. Fascinating (but ultimately not very rewarding). Just my 0.02c

Internecine? Who are you, fuzzalow?

;)

572cv
03-21-2016, 10:09 PM
So, if you look at the initial post ( always key) you can see that like-pal (weisan's winning term)!was asking a question. Sadly, his reason for said question was open for interpretation. The responses have been tangential and inflamitory.

Anyone who said something even potentially inflamitory without going back to the initial post and studying it should take a deep breath. IMO.

It is so easy to tear up a subject on the Internet, even here on the forum, and so hard to take the time to think things through before you respond. This may be why like-pal has not climbed back in ... Perhaps horrified at the responses, the drift. This forum is better than is thread. We have been generous to our fellows in so many ways. And that is how it should be.

I value everyone's constructive thoughts and wisdom, and cringe when there is venting or an ax to grind. I've never owned a single thing from eritchie, but I admire his contribution to cycling, and accept that he, like me, might not be perfect. I respect all of you for speaking your minds, but please, let it be willful and not hurtful. Intentional, but mindful.

If in doubt, have a glass of red, and sleep on it. You'll be channelling old friend Pete, and be glad you did. Especially if it's a good red. 🍷

cachagua
03-21-2016, 10:56 PM
"When you imply someone has a level you're not going to stoop to...you just did."

Thank you, if I may borrow this gem I'd like to add it to my repertoire.

Bruce K
03-22-2016, 04:21 AM
Probably time to move on.

If the intention was to discuss why a steel fork would crack like the picture, then please feel free to start a new thread that states the issue in that way.

BK