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is this fork bent?

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Old 09-02-20, 06:38 PM
  #26  
3alarmer 
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.
...BTW, I'm not arguing that the OP's fork is not bent, only that you can't always count on a photo on your monitor screen to diagnose such a thing. It's much better done in person.
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Old 09-02-20, 06:46 PM
  #27  
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Originally Posted by cyccommute
+1. Comparing the two pictures in the same orientation with the same line




.
...except they aren't the same orientation. Clearly, either the camera is more to the front of the OP's bike, or the fork and wheel are turned slightly toward the observer.
The only other explanation for being able to see the distant fork leg in the original picture would be x-ray vision. Note you can see only one fork leg on my second photo.

Now back to ignore.
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Old 09-02-20, 07:41 PM
  #28  
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Originally Posted by 3alarmer
...except they aren't the same orientation. Clearly, either the camera is more to the front of the OP's bike, or the fork and wheel are turned slightly toward the observer.
The only other explanation for being able to see the distant fork leg in the original picture would be x-ray vision. Note you can see only one fork leg on my second photo.

Now back to ignore.
By orientation, I meant that they are facing the same way. Even then they are close enough to clearly see that one fork is bent and the other isn’t. Photographs can tell us all kinds of things. Add in lines and they can tell you more. Frankly, I could see that the fork was bent in Crowsep original picture without the straight line. Not all photos lie.
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Old 09-02-20, 07:43 PM
  #29  
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Io know take it out of the bike,
she been riding it for the last year after hitting something ?
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Old 09-02-20, 08:43 PM
  #30  
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Originally Posted by 3alarmer
Once more, look at both the pictures I took of the same bike (same camera, different light conditions, thus different settings.) Someone should drop that red line on my first picture, and see where it ends up.
I did just that and came to the conclusion I posted.
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Old 09-02-20, 09:03 PM
  #31  
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Originally Posted by 3alarmer
...did you read the link I provided on photo distortion ? It's actually pretty interesting.

You can't simply state "the photo's seems to have been taken pretty close to perpendicular to the frame so the perspective should be accurate." with any certainty, because in any given case there's not enough context on what may or may not have induced the distortion. Once more, look at both the pictures I took of the same bike (same camera, different light conditions, thus different settings.) Someone should drop that red line on my first picture, and see where it ends up.

There are a million "fork looks bent to me" posts on teh Biekforooms. Not all of them are bent. There's a very good explanation for it, whether you want to believe me or not.
What I want to know is how the heck did you get up so much speed going backwards that you bent the seatstays applying the rear brake?
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Old 09-02-20, 09:29 PM
  #32  
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Originally Posted by 79pmooney
What I want to know is how the heck did you get up so much speed going backwards that you bent the seatstays applying the rear brake?
...it's a Colnago. They are fast in any direction. Colnago's are even fast sitting still.
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Old 09-02-20, 09:40 PM
  #33  
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Originally Posted by 3alarmer
...did you read the link I provided on photo distortion ? It's actually pretty interesting.

You can't simply state "the photo's seems to have been taken pretty close to perpendicular to the frame so the perspective should be accurate." with any certainty, because in any given case there's not enough context on what may or may not have induced the distortion. Once more, look at both the pictures I took of the same bike (same camera, different light conditions, thus different settings.) Someone should drop that red line on my first picture, and see where it ends up.

There are a million "fork looks bent to me" posts on teh Biekforooms. Not all of them are bent. There's a very good explanation for it, whether you want to believe me or not.
Okay, let’s find out how much you are ignoring me. I read the article and it doesn’t say what you think it says. The kinds of distortions described in the article aren’t occurring in Crowsep‘s picture. The photo doesn’t appear to have been taken with a telephoto nor with a wide angle lens. It’s a relatively close picture with a phone. There is little distortion in the picture, if any at all.

To show how little distortion there is, I put a grid across the picture for cropping. There is a line on the wall in the background that almost perfectly matches the horizontal grid line. There is another line on the wall slightly above that also aligns with the horizontal grid. The deviation from the grid is minimal.


The vertical line on the wall doesn’t match perfectly but it doesn’t deviate enough to account for the bend in the fork being a perspective problem. The line drawn on the picture also indicates that the fork is severely bent.

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Old 09-03-20, 04:46 AM
  #34  
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Originally Posted by fietsbob
Io know take it out of the bike,
she been riding it for the last year after hitting something ?
yea , she diden't noticed until i told her
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Old 09-03-20, 11:15 AM
  #35  
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It is pretty easy to simply look at the manufacturer's bike, on their own website to see how the fork is supposed to be, and yes, it is bent.

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Old 09-03-20, 11:41 AM
  #36  
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Originally Posted by CrowSeph
yea , she diden't noticed until i told her
If it's fine by her it's fine by me..
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Old 09-04-20, 04:54 PM
  #37  
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Originally Posted by phughes
It is pretty easy to simply look at the manufacturer's bike, on their own website to see how the fork is supposed to be, and yes, it is bent.

Look mate, don't you come on here with all your logic and googling and stuff... we've got a good argument going on about spherical distortion and fields of view and whatnot, and a picture of an unbent bike showing the OPs bike is way bent isn't helpful....
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Old 09-04-20, 07:39 PM
  #38  
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Originally Posted by Trevtassie
Look mate, don't you come on here with all your logic and googling and stuff... we've got a good argument going on about spherical distortion and fields of view and whatnot, and a picture of an unbent bike showing the OPs bike is way bent isn't helpful....

Don't worry, even with the injection of logic and actual facts, I know at least one in this thread who could still argue, even if he was the only one on the thread, I'm sure he would find a way.
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Old 09-04-20, 07:59 PM
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Originally Posted by phughes

Don't worry, even with the injection of logic and actual facts, I know at least one in this thread who could still argue, even if he was the only one on the thread, I'm sure he would find a way.
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Old 11-26-20, 08:32 AM
  #40  
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After a lot of time and a lot of wrong forks ordered (tnx stupid local shop) the bike is ready to be returned to the owner.
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Old 11-26-20, 10:30 AM
  #41  
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Nice job on the replacement.
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Old 11-26-20, 05:29 PM
  #42  
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Originally Posted by Mr. 66
Nice job on the replacement.
thank you
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Old 11-26-20, 07:46 PM
  #43  
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we had a neighborhood kid who I remember seeing purposely riding his bike into a wall, just for the hell of it, and his forks were bent back a bit too.
goofy kid.

I gotta love how folks are not believing what the photo shows. Clear, concise evidence. Man, what are you folks drinking in the water lately, sheesh.
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Old 11-27-20, 11:44 AM
  #44  
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Really well done. Thanks for the update.
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Old 11-27-20, 12:29 PM
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[QUOTE=CrowSeph;21806896]After a lot of time and a lot of wrong forks ordered (tnx stupid local shop) the bike is ready to be returned to the owner.
/QUOTE]
hey, were the headset races ovalized at all, or dinged by the ball bearings? Or did they replace the headset also?
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Old 11-27-20, 12:48 PM
  #46  
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Originally Posted by djb

I gotta love how folks are not believing what the photo shows. Clear, concise evidence. Man, what are you folks drinking in the water lately, sheesh.
...drinking water will kill you, man.
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Old 11-27-20, 01:54 PM
  #47  
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Originally Posted by 3alarmer
...drinking water will kill you, man.
especially if you fall out of a boat and can’t swim.
hey, are you from Lemington?
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Old 11-27-20, 02:40 PM
  #48  
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I had that once.
City bike, riding down a bridge, 40 km/h, front tyre went over an end of a dry twig, maybe 1.5 cm thick and 25 cm long.
The twig was catapulted up in the wheel, the spokes catched it, then it slammed into the fork, instantly stalling the wheel. I was thrown off, hit the ground and blackout for a long while. The bike was found 20 metres in front of me and the fork was bent not more than that.
Just to say, it needs some force to bend a fork.
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Old 11-27-20, 03:26 PM
  #49  
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Originally Posted by djb
especially if you fall out of a boat and can’t swim.
hey, are you from Lemington?
...speaking of lemmings, this thread is a classic example of how, on teh Biekforooms, a simple statement like, "Hey, you know a photograph is not the best way to diagnose a bent fork. The OP might be better off taking it to someone knowledgeable, in person, for a look see. Might be bent, but you can't tell from his pictures. This is something always best done with the fork in hand," eventually morphs into "That's just crazy talk."

Congratulations. There's a prize for this every year, and I intend to nominate you.
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Old 11-27-20, 09:55 PM
  #50  
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3alarmer, the Lemington, Ontario question was referring to tomatoes, cuz Lemington is the tomato capital of Ontario. I don't see it now, but coulda sworn that your user name had "tomato king" or something beside it, unless I'm losing it? Who knows, maybe I am.

I'm not sure how to take your comment though to be honest. The fork in the photo sure looks just like the kids bike on our street years ago, very close to the frame tube...... but hey, maybe I was wrong.
and why I asked the person if the head set was damaged when the replacement fork went in.
cheers
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