Bending back a bent head tube - is it worth trying?

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I have a bike that was in a major front end collision (I T-boned a car). The frame is steel and the bike bent at the head tube, the welds seem to be fine. Pictures below.



I am fully aware the appropriate thing to do in this situation is never ride the bike again. However, I loved this bike, it was built by a very talented builder, and I would like to bend the head tube back and build it up as a townie, basically to cruise around to the bar and the corner store.



My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back. While I realize this is not something anyone should advise anyone to do, people used to straighten our bent steel frames all the time.



My question is, is there a world where this ever goes well? Or is this absolutely too far gone?



enter image description here



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  • 1




    How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
    – Kibbee
    Sep 10 at 17:48







  • 3




    Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
    – Carel
    Sep 10 at 19:25










  • If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
    – Criggie
    Sep 11 at 3:22










  • Does the framebuilder still work? Would they repair one of theirs?
    – Criggie
    Sep 11 at 6:37














up vote
7
down vote

favorite












I have a bike that was in a major front end collision (I T-boned a car). The frame is steel and the bike bent at the head tube, the welds seem to be fine. Pictures below.



I am fully aware the appropriate thing to do in this situation is never ride the bike again. However, I loved this bike, it was built by a very talented builder, and I would like to bend the head tube back and build it up as a townie, basically to cruise around to the bar and the corner store.



My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back. While I realize this is not something anyone should advise anyone to do, people used to straighten our bent steel frames all the time.



My question is, is there a world where this ever goes well? Or is this absolutely too far gone?



enter image description here



enter image description here










share|improve this question



















  • 1




    How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
    – Kibbee
    Sep 10 at 17:48







  • 3




    Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
    – Carel
    Sep 10 at 19:25










  • If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
    – Criggie
    Sep 11 at 3:22










  • Does the framebuilder still work? Would they repair one of theirs?
    – Criggie
    Sep 11 at 6:37












up vote
7
down vote

favorite









up vote
7
down vote

favorite











I have a bike that was in a major front end collision (I T-boned a car). The frame is steel and the bike bent at the head tube, the welds seem to be fine. Pictures below.



I am fully aware the appropriate thing to do in this situation is never ride the bike again. However, I loved this bike, it was built by a very talented builder, and I would like to bend the head tube back and build it up as a townie, basically to cruise around to the bar and the corner store.



My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back. While I realize this is not something anyone should advise anyone to do, people used to straighten our bent steel frames all the time.



My question is, is there a world where this ever goes well? Or is this absolutely too far gone?



enter image description here



enter image description here










share|improve this question















I have a bike that was in a major front end collision (I T-boned a car). The frame is steel and the bike bent at the head tube, the welds seem to be fine. Pictures below.



I am fully aware the appropriate thing to do in this situation is never ride the bike again. However, I loved this bike, it was built by a very talented builder, and I would like to bend the head tube back and build it up as a townie, basically to cruise around to the bar and the corner store.



My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back. While I realize this is not something anyone should advise anyone to do, people used to straighten our bent steel frames all the time.



My question is, is there a world where this ever goes well? Or is this absolutely too far gone?



enter image description here



enter image description here







frames repair steerer crash






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edited Sep 10 at 18:04









Argenti Apparatus

29.7k23377




29.7k23377










asked Sep 10 at 17:10









colinnnn

20118




20118







  • 1




    How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
    – Kibbee
    Sep 10 at 17:48







  • 3




    Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
    – Carel
    Sep 10 at 19:25










  • If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
    – Criggie
    Sep 11 at 3:22










  • Does the framebuilder still work? Would they repair one of theirs?
    – Criggie
    Sep 11 at 6:37












  • 1




    How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
    – Kibbee
    Sep 10 at 17:48







  • 3




    Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
    – Carel
    Sep 10 at 19:25










  • If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
    – Criggie
    Sep 11 at 3:22










  • Does the framebuilder still work? Would they repair one of theirs?
    – Criggie
    Sep 11 at 6:37







1




1




How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
– Kibbee
Sep 10 at 17:48





How would you actually control where the bend was taking place when bending it back? You're probably just as likely (more likely?) to bend the frame in a different location than to actually fix the bend itself. It's not like with widening the rear drop outs where you can apply a minimal amount of force in precisely the spot you need to.
– Kibbee
Sep 10 at 17:48





3




3




Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
– Carel
Sep 10 at 19:25




Sorry to tell you, but there are just two places for this frame: on the dump or as a wall decoration. Anything else is a potential suicide.
– Carel
Sep 10 at 19:25












If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
– Criggie
Sep 11 at 3:22




If there was an insurance claim, surely cost of repair/replacement should be charged to the party at fault and paid by their insurance and excess/deductible ?
– Criggie
Sep 11 at 3:22












Does the framebuilder still work? Would they repair one of theirs?
– Criggie
Sep 11 at 6:37




Does the framebuilder still work? Would they repair one of theirs?
– Criggie
Sep 11 at 6:37










4 Answers
4






active

oldest

votes

















up vote
14
down vote



accepted










Not to disparage any of the very knowledgeable people here, but the best you'll get from a couple of pictures on the internet is a "good guess", or maybe even an "educated guess" but in my mind that's not very good when serious personal injury is on the line. Take the bike to a frame builder - preferably the one who built it for you, but any reputable one will work. Have him/her look at it and give you a professional opinion.



I'd imagine that any reputable frame builder would give you one of two answers based on two pictures: 1) nope, or 2) bring it in and let me look at it. The first answer is either "it's obviously way too far gone" or "I'm running from liability". The second indicates that he thinks there's a chance but needs to get an in-depth, hands on look before making a decision that could affect his reputation, business and livelihood.





My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back.




This line has been there from the beginning, and I meant to address it initially, but somehow I missed doing so. Unless you're very familiar with metal working, I'd suggest not doing this. You're likely to cause far more damage than you're fixing and not know that you've made it worse. If nothing else, putting the head tube in a vice and clamping down tight enough to bend the top & down tubes without the head tube moving may well crush (or at least ovalize to the point of non-function) the bearing races, or at the very least remove paint and open your nice steel frame up for rust.



A skilled frame builder will have the tools (a frame jig, the appropriate mandrels for bending without causing additional kinks, etc.) and the knowledge of how much straightening it will take before causing additional damage. Your builder may even be able to disassemble the frame, replace the damaged tubes (with original material), and repaint it so it's just as good as new.




As an anecdotal note, I was in a wreck many years ago on a steel frame - I went off the road and head-on into a concrete culvert. I ended up with a cracked vertebrae, and the bike ended up a mess. The fork, formerly with a nice forward sweep was perfectly straight (the only thing that stopped it from having a reverse curve was the tire hitting the down tube), and everything else looked off. I took the bike to a frame builder who put it on his jig. He determined that everything was 1/8 - 1/4" out of alignment, but he felt it was within reason of straightening, so I had him do the work.



The one item that he didn't/couldn't fix was a little wrinkle in the down tube right behind the head tube, very similar to yours (though I didn't have the wrinkle in the top tube). He said there was nothing he could do about it, but felt that it was safe enough that he would ride it. He returned the bike with one warning: if the paint at that wrinkle (which was still nicely attached) ever cracked, get off the bike immediately and never ride it again.



That was almost 30 years ago (OMG how did that happen!?!?) and I've put many thousands of miles on the bike since. I hung it up when componentry for it became difficult to find and when I got too, um... large to comfortably fit on a tight racing frame.



Despite the fact that I was a broke college kid at the time I wouldn't have felt comfortable with getting back on the bike without someone with some professional knowledge taking a look at it. (Of course, I didn't have an internet full of "wisdom" to consult, but still...)






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    I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.



    Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.



    Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.



    If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.






    share|improve this answer






















    • Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
      – colinnnn
      Sep 10 at 18:34






    • 12




      The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
      – Argenti Apparatus
      Sep 10 at 18:44

















    up vote
    11
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    The frame has undergone plastic deformation, which took it close to failure, and there might be small points of failure hidden under the paint, for all we know. The fact that it has completely buckled on the downtube seems like a bad sign to me. You will need to plastically deform it again, meaning damage the metal again.



    The article you linked to suggests that for damage this severe, you would cut out the damaged section and splice in a new section. This would be difficult so close to the head tube.



    The upside of having a sentimental favorite as a beater does not override the downside of catastrophic failure for me. Then again, if this is steel, you'd probably get some warning it was about to fail--but I'd never feel comfortable riding it.






    share|improve this answer
















    • 1




      You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
      – Toby Speight
      Sep 11 at 8:34










    • I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
      – KeithWM
      Sep 11 at 10:10

















    up vote
    10
    down vote













    The degree of crumpling is relatively unusual and suggests a thin walled, high strength tube selection, which also frequently goes along with handbuilt frames. The material property that is the biggest factor in whether the frame would eventually fail is ductility, the material's resistance to flaws or stresses in the crystalline structure of the metal propagating out, which tubes of this sort have the least of of any steel bike tubes.



    More mundane steel frames are often pretty well able to be re-aligned from front end impacts like this. They also buckle less severely. It's never a perfectly safe thing that has no risk of failure, but a lot of bikes in the world, especially the less developed world, are running around post this kind of realignment. The comparison here is pretty apples to oranges. It actually probably has some odds of breaking all the way in the realignment process. There's no way I would trust it.



    The upshot here is that this kind of thing can be a little more repairable than people give credit for if you're willing for the bike to take on a little different form and have a framebuilder fix it. In this case for example a bilaminate headtube could be fashioned.






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      4 Answers
      4






      active

      oldest

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      4 Answers
      4






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes








      up vote
      14
      down vote



      accepted










      Not to disparage any of the very knowledgeable people here, but the best you'll get from a couple of pictures on the internet is a "good guess", or maybe even an "educated guess" but in my mind that's not very good when serious personal injury is on the line. Take the bike to a frame builder - preferably the one who built it for you, but any reputable one will work. Have him/her look at it and give you a professional opinion.



      I'd imagine that any reputable frame builder would give you one of two answers based on two pictures: 1) nope, or 2) bring it in and let me look at it. The first answer is either "it's obviously way too far gone" or "I'm running from liability". The second indicates that he thinks there's a chance but needs to get an in-depth, hands on look before making a decision that could affect his reputation, business and livelihood.





      My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back.




      This line has been there from the beginning, and I meant to address it initially, but somehow I missed doing so. Unless you're very familiar with metal working, I'd suggest not doing this. You're likely to cause far more damage than you're fixing and not know that you've made it worse. If nothing else, putting the head tube in a vice and clamping down tight enough to bend the top & down tubes without the head tube moving may well crush (or at least ovalize to the point of non-function) the bearing races, or at the very least remove paint and open your nice steel frame up for rust.



      A skilled frame builder will have the tools (a frame jig, the appropriate mandrels for bending without causing additional kinks, etc.) and the knowledge of how much straightening it will take before causing additional damage. Your builder may even be able to disassemble the frame, replace the damaged tubes (with original material), and repaint it so it's just as good as new.




      As an anecdotal note, I was in a wreck many years ago on a steel frame - I went off the road and head-on into a concrete culvert. I ended up with a cracked vertebrae, and the bike ended up a mess. The fork, formerly with a nice forward sweep was perfectly straight (the only thing that stopped it from having a reverse curve was the tire hitting the down tube), and everything else looked off. I took the bike to a frame builder who put it on his jig. He determined that everything was 1/8 - 1/4" out of alignment, but he felt it was within reason of straightening, so I had him do the work.



      The one item that he didn't/couldn't fix was a little wrinkle in the down tube right behind the head tube, very similar to yours (though I didn't have the wrinkle in the top tube). He said there was nothing he could do about it, but felt that it was safe enough that he would ride it. He returned the bike with one warning: if the paint at that wrinkle (which was still nicely attached) ever cracked, get off the bike immediately and never ride it again.



      That was almost 30 years ago (OMG how did that happen!?!?) and I've put many thousands of miles on the bike since. I hung it up when componentry for it became difficult to find and when I got too, um... large to comfortably fit on a tight racing frame.



      Despite the fact that I was a broke college kid at the time I wouldn't have felt comfortable with getting back on the bike without someone with some professional knowledge taking a look at it. (Of course, I didn't have an internet full of "wisdom" to consult, but still...)






      share|improve this answer


























        up vote
        14
        down vote



        accepted










        Not to disparage any of the very knowledgeable people here, but the best you'll get from a couple of pictures on the internet is a "good guess", or maybe even an "educated guess" but in my mind that's not very good when serious personal injury is on the line. Take the bike to a frame builder - preferably the one who built it for you, but any reputable one will work. Have him/her look at it and give you a professional opinion.



        I'd imagine that any reputable frame builder would give you one of two answers based on two pictures: 1) nope, or 2) bring it in and let me look at it. The first answer is either "it's obviously way too far gone" or "I'm running from liability". The second indicates that he thinks there's a chance but needs to get an in-depth, hands on look before making a decision that could affect his reputation, business and livelihood.





        My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back.




        This line has been there from the beginning, and I meant to address it initially, but somehow I missed doing so. Unless you're very familiar with metal working, I'd suggest not doing this. You're likely to cause far more damage than you're fixing and not know that you've made it worse. If nothing else, putting the head tube in a vice and clamping down tight enough to bend the top & down tubes without the head tube moving may well crush (or at least ovalize to the point of non-function) the bearing races, or at the very least remove paint and open your nice steel frame up for rust.



        A skilled frame builder will have the tools (a frame jig, the appropriate mandrels for bending without causing additional kinks, etc.) and the knowledge of how much straightening it will take before causing additional damage. Your builder may even be able to disassemble the frame, replace the damaged tubes (with original material), and repaint it so it's just as good as new.




        As an anecdotal note, I was in a wreck many years ago on a steel frame - I went off the road and head-on into a concrete culvert. I ended up with a cracked vertebrae, and the bike ended up a mess. The fork, formerly with a nice forward sweep was perfectly straight (the only thing that stopped it from having a reverse curve was the tire hitting the down tube), and everything else looked off. I took the bike to a frame builder who put it on his jig. He determined that everything was 1/8 - 1/4" out of alignment, but he felt it was within reason of straightening, so I had him do the work.



        The one item that he didn't/couldn't fix was a little wrinkle in the down tube right behind the head tube, very similar to yours (though I didn't have the wrinkle in the top tube). He said there was nothing he could do about it, but felt that it was safe enough that he would ride it. He returned the bike with one warning: if the paint at that wrinkle (which was still nicely attached) ever cracked, get off the bike immediately and never ride it again.



        That was almost 30 years ago (OMG how did that happen!?!?) and I've put many thousands of miles on the bike since. I hung it up when componentry for it became difficult to find and when I got too, um... large to comfortably fit on a tight racing frame.



        Despite the fact that I was a broke college kid at the time I wouldn't have felt comfortable with getting back on the bike without someone with some professional knowledge taking a look at it. (Of course, I didn't have an internet full of "wisdom" to consult, but still...)






        share|improve this answer
























          up vote
          14
          down vote



          accepted







          up vote
          14
          down vote



          accepted






          Not to disparage any of the very knowledgeable people here, but the best you'll get from a couple of pictures on the internet is a "good guess", or maybe even an "educated guess" but in my mind that's not very good when serious personal injury is on the line. Take the bike to a frame builder - preferably the one who built it for you, but any reputable one will work. Have him/her look at it and give you a professional opinion.



          I'd imagine that any reputable frame builder would give you one of two answers based on two pictures: 1) nope, or 2) bring it in and let me look at it. The first answer is either "it's obviously way too far gone" or "I'm running from liability". The second indicates that he thinks there's a chance but needs to get an in-depth, hands on look before making a decision that could affect his reputation, business and livelihood.





          My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back.




          This line has been there from the beginning, and I meant to address it initially, but somehow I missed doing so. Unless you're very familiar with metal working, I'd suggest not doing this. You're likely to cause far more damage than you're fixing and not know that you've made it worse. If nothing else, putting the head tube in a vice and clamping down tight enough to bend the top & down tubes without the head tube moving may well crush (or at least ovalize to the point of non-function) the bearing races, or at the very least remove paint and open your nice steel frame up for rust.



          A skilled frame builder will have the tools (a frame jig, the appropriate mandrels for bending without causing additional kinks, etc.) and the knowledge of how much straightening it will take before causing additional damage. Your builder may even be able to disassemble the frame, replace the damaged tubes (with original material), and repaint it so it's just as good as new.




          As an anecdotal note, I was in a wreck many years ago on a steel frame - I went off the road and head-on into a concrete culvert. I ended up with a cracked vertebrae, and the bike ended up a mess. The fork, formerly with a nice forward sweep was perfectly straight (the only thing that stopped it from having a reverse curve was the tire hitting the down tube), and everything else looked off. I took the bike to a frame builder who put it on his jig. He determined that everything was 1/8 - 1/4" out of alignment, but he felt it was within reason of straightening, so I had him do the work.



          The one item that he didn't/couldn't fix was a little wrinkle in the down tube right behind the head tube, very similar to yours (though I didn't have the wrinkle in the top tube). He said there was nothing he could do about it, but felt that it was safe enough that he would ride it. He returned the bike with one warning: if the paint at that wrinkle (which was still nicely attached) ever cracked, get off the bike immediately and never ride it again.



          That was almost 30 years ago (OMG how did that happen!?!?) and I've put many thousands of miles on the bike since. I hung it up when componentry for it became difficult to find and when I got too, um... large to comfortably fit on a tight racing frame.



          Despite the fact that I was a broke college kid at the time I wouldn't have felt comfortable with getting back on the bike without someone with some professional knowledge taking a look at it. (Of course, I didn't have an internet full of "wisdom" to consult, but still...)






          share|improve this answer














          Not to disparage any of the very knowledgeable people here, but the best you'll get from a couple of pictures on the internet is a "good guess", or maybe even an "educated guess" but in my mind that's not very good when serious personal injury is on the line. Take the bike to a frame builder - preferably the one who built it for you, but any reputable one will work. Have him/her look at it and give you a professional opinion.



          I'd imagine that any reputable frame builder would give you one of two answers based on two pictures: 1) nope, or 2) bring it in and let me look at it. The first answer is either "it's obviously way too far gone" or "I'm running from liability". The second indicates that he thinks there's a chance but needs to get an in-depth, hands on look before making a decision that could affect his reputation, business and livelihood.





          My plan is to put the head tube in a vice and use the frame as a lever to bend the head tube back.




          This line has been there from the beginning, and I meant to address it initially, but somehow I missed doing so. Unless you're very familiar with metal working, I'd suggest not doing this. You're likely to cause far more damage than you're fixing and not know that you've made it worse. If nothing else, putting the head tube in a vice and clamping down tight enough to bend the top & down tubes without the head tube moving may well crush (or at least ovalize to the point of non-function) the bearing races, or at the very least remove paint and open your nice steel frame up for rust.



          A skilled frame builder will have the tools (a frame jig, the appropriate mandrels for bending without causing additional kinks, etc.) and the knowledge of how much straightening it will take before causing additional damage. Your builder may even be able to disassemble the frame, replace the damaged tubes (with original material), and repaint it so it's just as good as new.




          As an anecdotal note, I was in a wreck many years ago on a steel frame - I went off the road and head-on into a concrete culvert. I ended up with a cracked vertebrae, and the bike ended up a mess. The fork, formerly with a nice forward sweep was perfectly straight (the only thing that stopped it from having a reverse curve was the tire hitting the down tube), and everything else looked off. I took the bike to a frame builder who put it on his jig. He determined that everything was 1/8 - 1/4" out of alignment, but he felt it was within reason of straightening, so I had him do the work.



          The one item that he didn't/couldn't fix was a little wrinkle in the down tube right behind the head tube, very similar to yours (though I didn't have the wrinkle in the top tube). He said there was nothing he could do about it, but felt that it was safe enough that he would ride it. He returned the bike with one warning: if the paint at that wrinkle (which was still nicely attached) ever cracked, get off the bike immediately and never ride it again.



          That was almost 30 years ago (OMG how did that happen!?!?) and I've put many thousands of miles on the bike since. I hung it up when componentry for it became difficult to find and when I got too, um... large to comfortably fit on a tight racing frame.



          Despite the fact that I was a broke college kid at the time I wouldn't have felt comfortable with getting back on the bike without someone with some professional knowledge taking a look at it. (Of course, I didn't have an internet full of "wisdom" to consult, but still...)







          share|improve this answer














          share|improve this answer



          share|improve this answer








          edited Sep 11 at 21:03

























          answered Sep 11 at 11:55









          FreeMan

          851313




          851313




















              up vote
              14
              down vote













              I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.



              Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.



              Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.



              If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.






              share|improve this answer






















              • Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
                – colinnnn
                Sep 10 at 18:34






              • 12




                The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
                – Argenti Apparatus
                Sep 10 at 18:44














              up vote
              14
              down vote













              I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.



              Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.



              Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.



              If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.






              share|improve this answer






















              • Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
                – colinnnn
                Sep 10 at 18:34






              • 12




                The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
                – Argenti Apparatus
                Sep 10 at 18:44












              up vote
              14
              down vote










              up vote
              14
              down vote









              I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.



              Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.



              Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.



              If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.






              share|improve this answer














              I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.



              Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.



              Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.



              If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.







              share|improve this answer














              share|improve this answer



              share|improve this answer








              edited Sep 10 at 18:46

























              answered Sep 10 at 17:46









              Argenti Apparatus

              29.7k23377




              29.7k23377











              • Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
                – colinnnn
                Sep 10 at 18:34






              • 12




                The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
                – Argenti Apparatus
                Sep 10 at 18:44
















              • Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
                – colinnnn
                Sep 10 at 18:34






              • 12




                The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
                – Argenti Apparatus
                Sep 10 at 18:44















              Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
              – colinnnn
              Sep 10 at 18:34




              Gotcha. I'm going to try to straighten anyways, since I have nothing to lose. Assuming I don't crush/ovalize the head tube in the "un-bending" process, you would still worry about the frame collapsing? Like the metal shearing somehow?
              – colinnnn
              Sep 10 at 18:34




              12




              12




              The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
              – Argenti Apparatus
              Sep 10 at 18:44




              The point of my answer is that yes, I absolutely would worry about the frame cracking and collapsing. The tube wall of the downtube just behind the headtube is folded almost 90 degrees. Localized deformation and stress weakens metal enormously. A crack would probably form along the line of that fold. Hit a bump and the headtube would likely rip right off sending you face first into the ground.
              – Argenti Apparatus
              Sep 10 at 18:44










              up vote
              11
              down vote













              The frame has undergone plastic deformation, which took it close to failure, and there might be small points of failure hidden under the paint, for all we know. The fact that it has completely buckled on the downtube seems like a bad sign to me. You will need to plastically deform it again, meaning damage the metal again.



              The article you linked to suggests that for damage this severe, you would cut out the damaged section and splice in a new section. This would be difficult so close to the head tube.



              The upside of having a sentimental favorite as a beater does not override the downside of catastrophic failure for me. Then again, if this is steel, you'd probably get some warning it was about to fail--but I'd never feel comfortable riding it.






              share|improve this answer
















              • 1




                You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
                – Toby Speight
                Sep 11 at 8:34










              • I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
                – KeithWM
                Sep 11 at 10:10














              up vote
              11
              down vote













              The frame has undergone plastic deformation, which took it close to failure, and there might be small points of failure hidden under the paint, for all we know. The fact that it has completely buckled on the downtube seems like a bad sign to me. You will need to plastically deform it again, meaning damage the metal again.



              The article you linked to suggests that for damage this severe, you would cut out the damaged section and splice in a new section. This would be difficult so close to the head tube.



              The upside of having a sentimental favorite as a beater does not override the downside of catastrophic failure for me. Then again, if this is steel, you'd probably get some warning it was about to fail--but I'd never feel comfortable riding it.






              share|improve this answer
















              • 1




                You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
                – Toby Speight
                Sep 11 at 8:34










              • I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
                – KeithWM
                Sep 11 at 10:10












              up vote
              11
              down vote










              up vote
              11
              down vote









              The frame has undergone plastic deformation, which took it close to failure, and there might be small points of failure hidden under the paint, for all we know. The fact that it has completely buckled on the downtube seems like a bad sign to me. You will need to plastically deform it again, meaning damage the metal again.



              The article you linked to suggests that for damage this severe, you would cut out the damaged section and splice in a new section. This would be difficult so close to the head tube.



              The upside of having a sentimental favorite as a beater does not override the downside of catastrophic failure for me. Then again, if this is steel, you'd probably get some warning it was about to fail--but I'd never feel comfortable riding it.






              share|improve this answer












              The frame has undergone plastic deformation, which took it close to failure, and there might be small points of failure hidden under the paint, for all we know. The fact that it has completely buckled on the downtube seems like a bad sign to me. You will need to plastically deform it again, meaning damage the metal again.



              The article you linked to suggests that for damage this severe, you would cut out the damaged section and splice in a new section. This would be difficult so close to the head tube.



              The upside of having a sentimental favorite as a beater does not override the downside of catastrophic failure for me. Then again, if this is steel, you'd probably get some warning it was about to fail--but I'd never feel comfortable riding it.







              share|improve this answer












              share|improve this answer



              share|improve this answer










              answered Sep 10 at 18:46









              Adam Rice

              4,8661330




              4,8661330







              • 1




                You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
                – Toby Speight
                Sep 11 at 8:34










              • I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
                – KeithWM
                Sep 11 at 10:10












              • 1




                You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
                – Toby Speight
                Sep 11 at 8:34










              • I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
                – KeithWM
                Sep 11 at 10:10







              1




              1




              You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
              – Toby Speight
              Sep 11 at 8:34




              You might not get enough warning of imminent failure if you hit a pothole or kerb - perhaps not enough to safely dismount, never mind to ride it home to your other bike.
              – Toby Speight
              Sep 11 at 8:34












              I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
              – KeithWM
              Sep 11 at 10:10




              I'd look into some other way of preserving your beloved bike without running (riding) the risk of it killing you. Pinterest might be more helpful.
              – KeithWM
              Sep 11 at 10:10










              up vote
              10
              down vote













              The degree of crumpling is relatively unusual and suggests a thin walled, high strength tube selection, which also frequently goes along with handbuilt frames. The material property that is the biggest factor in whether the frame would eventually fail is ductility, the material's resistance to flaws or stresses in the crystalline structure of the metal propagating out, which tubes of this sort have the least of of any steel bike tubes.



              More mundane steel frames are often pretty well able to be re-aligned from front end impacts like this. They also buckle less severely. It's never a perfectly safe thing that has no risk of failure, but a lot of bikes in the world, especially the less developed world, are running around post this kind of realignment. The comparison here is pretty apples to oranges. It actually probably has some odds of breaking all the way in the realignment process. There's no way I would trust it.



              The upshot here is that this kind of thing can be a little more repairable than people give credit for if you're willing for the bike to take on a little different form and have a framebuilder fix it. In this case for example a bilaminate headtube could be fashioned.






              share|improve this answer
























                up vote
                10
                down vote













                The degree of crumpling is relatively unusual and suggests a thin walled, high strength tube selection, which also frequently goes along with handbuilt frames. The material property that is the biggest factor in whether the frame would eventually fail is ductility, the material's resistance to flaws or stresses in the crystalline structure of the metal propagating out, which tubes of this sort have the least of of any steel bike tubes.



                More mundane steel frames are often pretty well able to be re-aligned from front end impacts like this. They also buckle less severely. It's never a perfectly safe thing that has no risk of failure, but a lot of bikes in the world, especially the less developed world, are running around post this kind of realignment. The comparison here is pretty apples to oranges. It actually probably has some odds of breaking all the way in the realignment process. There's no way I would trust it.



                The upshot here is that this kind of thing can be a little more repairable than people give credit for if you're willing for the bike to take on a little different form and have a framebuilder fix it. In this case for example a bilaminate headtube could be fashioned.






                share|improve this answer






















                  up vote
                  10
                  down vote










                  up vote
                  10
                  down vote









                  The degree of crumpling is relatively unusual and suggests a thin walled, high strength tube selection, which also frequently goes along with handbuilt frames. The material property that is the biggest factor in whether the frame would eventually fail is ductility, the material's resistance to flaws or stresses in the crystalline structure of the metal propagating out, which tubes of this sort have the least of of any steel bike tubes.



                  More mundane steel frames are often pretty well able to be re-aligned from front end impacts like this. They also buckle less severely. It's never a perfectly safe thing that has no risk of failure, but a lot of bikes in the world, especially the less developed world, are running around post this kind of realignment. The comparison here is pretty apples to oranges. It actually probably has some odds of breaking all the way in the realignment process. There's no way I would trust it.



                  The upshot here is that this kind of thing can be a little more repairable than people give credit for if you're willing for the bike to take on a little different form and have a framebuilder fix it. In this case for example a bilaminate headtube could be fashioned.






                  share|improve this answer












                  The degree of crumpling is relatively unusual and suggests a thin walled, high strength tube selection, which also frequently goes along with handbuilt frames. The material property that is the biggest factor in whether the frame would eventually fail is ductility, the material's resistance to flaws or stresses in the crystalline structure of the metal propagating out, which tubes of this sort have the least of of any steel bike tubes.



                  More mundane steel frames are often pretty well able to be re-aligned from front end impacts like this. They also buckle less severely. It's never a perfectly safe thing that has no risk of failure, but a lot of bikes in the world, especially the less developed world, are running around post this kind of realignment. The comparison here is pretty apples to oranges. It actually probably has some odds of breaking all the way in the realignment process. There's no way I would trust it.



                  The upshot here is that this kind of thing can be a little more repairable than people give credit for if you're willing for the bike to take on a little different form and have a framebuilder fix it. In this case for example a bilaminate headtube could be fashioned.







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered Sep 10 at 20:07









                  Nathan Knutson

                  21.6k11353




                  21.6k11353



























                       

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