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  1. #1
    wounded knee
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    Pugsley frame failure

    I know I seen a thread on this a while back I have searched in vain and found nothing.
    About 2 weeks ago I had a frame failure on my 2010 Surly Pugsley, behind the seat stay right where the failures were on the 2012 if I remember correctly.



    My local shop Valley Cycles was nice enough to take care of all the Warranty paperwork and headaches that go along with it for me.

    They got the ok to send it back but no call tag, and when they asked for one there was no reply? So I'm going to have to foot the bill for shipping which acording to them is not the norm.

    Anyone else that went through this how long did it take to get the new frame?
    Did you pay shipping?
    I know I'm going to have to pay the shop for switching all the parts over, honestly I just want my favorite bike back in time for Winter.
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  2. #2
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    I was looking for that old thread too, no idea what happened to it. Surly should take care of the shipping, they are usually really good with warranty issues. Have your LBS call them again tomorrow for a call tag. Your LBS will have to pack the frame to send back to Surly on their own dime, so I'd recommend dropping off a 12 pack of beer shortly before closing
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  3. #3
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    Iíve had several frames from small builders and big manufactures break over the years and warrantied many customer frames. Iíd say itís about 50/ 50 when it comes to manufacturers paying for the return shipping. Itís always worth having your shop ask, but jeeze, youíve got a few seasons of riding on this thing, $35 to get a new frame is a pretty sweet deal if you ask me. As long as it is warranty, and they have a frame in your size in stock, I bet youíll have a
    shiny new frame by the end of the week.

  4. #4
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    LBS took in my damaged frame (7 months of riding on mine before I noticed the cracks) and received a warranty frame from Surly. There was some arm wrestling over who was to pay for shipping to an fro but between them but I was not involved in that. Also said bike shop was under new ownership after I purchased my Pugsley, so the frame/parts swap was on my dime albeit discounted. I like Surly and the bike shop so I paid the bill and went for a ride! No harm, no foul.

  5. #5
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    Quote Originally Posted by Yoreskillz View Post
    LBS took in my damaged frame (7 months of riding on mine before I noticed the cracks) and received a warranty frame from Surly. There was some arm wrestling over who was to pay for shipping to an fro but between them but I was not involved in that. Also said bike shop was under new ownership after I purchased my Pugsley, so the frame/parts swap was on my dime albeit discounted. I like Surly and the bike shop so I paid the bill and went for a ride! No harm, no foul.
    this seems reasonable

  6. #6
    wounded knee
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    Honestly I don'y mind paying the freight out $56.00, and the changeover of parts from my LBS, I also have them regreasing all the bearings, running all new cables, ect.
    I have had 2 and a half years of riding my favorite mountain bike, I just hope to hear something next week about when I'll see the new frame.
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  7. #7
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    ^Cheers for positive news

  8. #8
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    Sorry to hear that...are u getting the yellow or red frame

    or do they have white frames still in stock?
    Your pugs was the bike that convinced me that I had to get a fat bike. Rode it briefly at the moon over a year ago. Surprised to see the frame crack, that bike seemed like a tank!!!!

  9. #9
    wounded knee
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    Quote Originally Posted by Team Honeybadger View Post
    or do they have white frames still in stock?
    Your pugs was the bike that convinced me that I had to get a fat bike. Rode it briefly at the moon over a year ago. Surprised to see the frame crack, that bike seemed like a tank!!!!
    I wish they had the white, from what I hear I'm getting a Yellow frame, would of rathered the Red, maybe it's time for a change though, can't wait to get it back.
    I'm allways happy to let people ride it, love hearing them say WOW I thought it would be slow and cumbersome, and see the reaction on their faces.
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  10. #10
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    THere are more than a handful of unique reports of the OP's type of failure on the Amazing Surly Pugsley Facebook page... not good..

  11. #11
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    Local guy had this happen on 3 white frames in a fairly short amount of time. The first one after a year or so, and the others a few months afterwards for each. His yellow one is holding up good so far. The design of the rear seat stay is different on the new yellow frame. He's not riding it super hard, sand rides and single track with no hucking off of big drops or anything.

  12. #12
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    Quote Originally Posted by sfuller View Post
    Local guy had this happen on 3 white frames in a fairly short amount of time...
    Is the frame is on the small side for him and he's using a longer seatpost to make up for it? (ie insertion depth insufficient). Or is he using a stiff seatpost?

    This is happening often enough that Surly need to reinforce that area to make it foolproof.

    This sort of problem plagues manufacturers of well-used folding bikes which tend to use long seatposts (although most don't get ridden far enough for this to become evident)
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  13. #13
    wounded knee
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    The good news is my replacement frame should be here by Friday, the bad news is it might be a White one, I don't understand why they would still be shipping these frames out for replacement ones when they know there is a problem with them, I'm going to be inspecting it every ride.
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  14. #14
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    Quote Originally Posted by boogman View Post
    THere are more than a handful of unique reports of the OP's type of failure on the Amazing Surly Pugsley Facebook page... not good..
    Yeah I saw that. Also a lot of assumptions being made there about what the cause is that are pretty far fetched.

  15. #15
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    if they changed the design on the yellow and red frames, safe to say the Necro pug has the same design as the white? and potentially same issue?

  16. #16
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    I can't visualize how the forces work. Could someone explain how the curved piece as opposed to the straight piece makes the frame crack?

  17. #17
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    Pictures?

    Quote Originally Posted by kuan View Post
    I can't visualize how the forces work. Could someone explain how the curved piece as opposed to the straight piece makes the frame crack?
    I'm not sure exactly what part you're referring to but all other things being equal a curved piece is more flexible than a straight one. Often used by designers to give a frame "compliance" (makes it ride softer)

    If you're talking about the strut between the seatstays (curved on my Pugs) a curved one will allow more flexing where the seatstays join the seat tube (where those cracks are) than a straight one.

    Designs need to be flexible, the trick is spreading the flexibility around so a single area is not overloaded. (beyond the material's fatigue limit) A straight strut might just move the cracking failures to another area.

    I wonder if the cracked frames are being ridden hard? (jumps, wheelies, hammered?)
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  18. #18
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    Ah I see. Makes perfect sense now. It's too flexy and the welds take the brunt of it, not the tubing. Thanks.

  19. #19
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    Haz...?

    It is worthwhile to note that it is not the weld bead itself that is cracked; it's in the seat tube immediately adjacent to the weld---this is a typical weld failure in the "Heat Affected Zone". This could be the result of poor weld technique, wrong materials or skipping possible post-welding heat treatment (normalizing); not necessarily poor geometry/design.

    My "Curry Squirt" Pugs (no cracks thus far) has much smaller weld beads in the area shown in the OP photo; this may be of some significance. I also noticed that on the red frame (still has a curved brace) pictured on the Surly site the tubes are now spaced further apart so the joints are more on the side of the seat tube.
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  20. #20
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    Quote Originally Posted by dirtrider6 View Post
    The good news is my replacement frame should be here by Friday, the bad news is it might be a White one, I don't understand why they would still be shipping these frames out for replacement ones when they know there is a problem with them, I'm going to be inspecting it every ride.
    I was just communicating with Surly about this problem and I think form a manufacturing point of view there is very few bikes that are failing in this model (white) to send out a different model.

    Most of the white ones (like mine) are fine and good bikes. I know of others that have this model and their bikes are OK. So it is just an anomaly. A pain that it has happen to some, like yourself and it did cause me to check my bike and contact Surly. The good news is that Surly is such a great company to deal with and that they take good care of there customer.

    I hope all goes well with your new frame and I will be watching mine more closely.

  21. #21
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    Quote Originally Posted by pliebenberg View Post
    It is worthwhile to note that it is not the weld bead itself that is cracked; it's in the seat tube immediately adjacent to the weld---this is a typical weld failure in the "Heat Affected Zone". This could be the result of poor weld technique, wrong materials or skipping possible post-welding heat treatment (normalizing); not necessarily poor geometry/design.

    My "Curry Squirt" Pugs (no cracks thus far) has much smaller weld beads in the area shown in the OP photo; this may be of some significance. I also noticed that on the red frame (still has a curved brace) pictured on the Surly site the tubes are now spaced further apart so the joints are more on the side of the seat tube.
    ^^^
    Yep.

    Failure in the HAZ.

  22. #22
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    Lots of activities on the the amazing surly pugsley facebook page regarding the frame failure.. Pop corn time!

    Hpefully this wont degrade white pugs' resale value.. I have fatter bikes within my view

  23. #23
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    Quote Originally Posted by pliebenberg View Post
    It is worthwhile to note that it is not the weld bead itself that is cracked; it's in the seat tube immediately adjacent to the weld---this is a typical weld failure in the "Heat Affected Zone". This could be the result of poor weld technique, wrong materials or skipping possible post-welding heat treatment (normalizing); not necessarily poor geometry/design.

    My "Curry Squirt" Pugs (no cracks thus far) has much smaller weld beads in the area shown in the OP photo; this may be of some significance. I also noticed that on the red frame (still has a curved brace) pictured on the Surly site the tubes are now spaced further apart so the joints are more on the side of the seat tube.
    Bingo! My first gen Pug has no problems and most likely never will and it's curved. It's absolutely absurd to claim that is the issue when its just a QC issue with the welds. Lots of claims being made by non metallurgists and people who have never TIG welded 4130. I'm sure Surly will straighten it out and people should be going to them and/or their LBS about it.

  24. #24
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    Quote Originally Posted by boogman View Post
    Lots of activities on the the amazing surly pugsley facebook page regarding the frame failure.. Pop corn time!

    Hpefully this wont degrade white pugs' resale value.. I have fatter bikes within my view
    Mostly one persons crusade from what I can see, and he's barking up the wrong tree.

  25. #25
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    I've recently bought a used Pugs frame which had a similar crack and then had it repaired. So if out of warranty it's still fixable. Now awaiting powder coat and build up.

    Pugsley frame failure-img_3600.jpg

    Pugsley frame failure-img_3603.jpg

  26. #26
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    Quote Originally Posted by andyh2 View Post
    I've recently bought a used Pugs frame which had a similar crack and then had it repaired. So if out of warranty it's still fixable....
    That's the beauty of a steel frame. Just about any local metalworker can fix them.

    A crack is not the end of the world. Surly will honour their warranty, and if out of warranty, a fix is cheap enough.
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  27. #27
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    I'm on my second frame and it is also starting to crack!

  28. #28
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    dang, saw this thread, went to check my 2011 white pugs... Cracked in the same spot. WTF

  29. #29
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    Quote Originally Posted by trail rida View Post
    dang, saw this thread, went to check my 2011 white pugs... Cracked in the same spot. WTF
    Oops! I'd better go and check mine....
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    Quote Originally Posted by trail rida View Post
    dang, saw this thread, went to check my 2011 white pugs... Cracked in the same spot. WTF
    I checked mine when this thread first came out. No problems at frame is holding up fine.

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    damn man! I know internet reports of issues is not representative of the true percentage.. but all things being equal, I don't see this type of reports of failures on other bikes.. therefore it surely it can't just be a fluke manufacturing defect...?

  32. #32
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    Quote Originally Posted by Velobike View Post
    Is the frame is on the small side for him and he's using a longer seatpost to make up for it? (ie insertion depth insufficient). Or is he using a stiff seatpost?

    This is happening often enough that Surly need to reinforce that area to make it foolproof.

    This sort of problem plagues manufacturers of well-used folding bikes which tend to use long seatposts (although most don't get ridden far enough for this to become evident)
    Frame is the right size for him. He does use a Cane Creek Thudbuster on his bike, but it was inserted well into the seat tube (past the seat/top tube joint and well past the seat stays.

  33. #33
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    How much frame flex?

    This much:
    <iframe width="853" height="480" src="http://www.youtube.com/embed/ry7diWP6hR8?rel=0" frameborder="0" allowfullscreen></iframe>
    Not exactly related to this frame cracking problem, I've converted my Pugs to belt drive. In the process it's become necessary to know how much the frame flexes. (To see if it was within the specifications for the Gates Carbon Drive system)

    The video shows me (at 200#) "hammering" (off the saddle) up a 20% grade. The gearing is 39/28 F/R and the cranks have 175mm arms.

    The video is inverted because that's how the GoPro was mounted as was the scale; it's also being played at 1/2 speed. If you can't see the scale plainly then you may want to watch the vid directly on YouTube with the setting on HD.

    The test set-up is a rigid aluminum bar attached in the vicinity of the Bottom Bracket (the chain guide lug) with the back end having a scale (from an old tape measure blade) fixed with 1/16" markings . Under this heavy pedaling the frame is flexing laterally about 1/4"; during "normal" riding it's still flexing about 1/16".

    I'm sort of getting away with the flexing in regards to the belt but I think it's more than Gates would approve.

    In regards to the cracking; it "is what it is"---if solely due to flexing I'd expect to be seeing failure more so at the chain-stay/BB juncture than at the lighter loaded seat-stay/ST juncture. I still suspect a failure in the fabrication process at the factory; not the design.
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  34. #34
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    Quote Originally Posted by boogman View Post
    damn man! I know internet reports of issues is not representative of the true percentage.. but all things being equal, I don't see this type of reports of failures on other bikes.. therefore it surely it can't just be a fluke manufacturing defect...?
    Sure it can. While I wouldn't normally preheat or need to stress relieve 4130 this thin if I was welding it, letting it cool too fast after welding (TIG) it then it would become exceptionally brittle right where it's failing.

    These are made in Taiwan right? Not at all out of the question to have a new guy make mistakes like this on a production line (cooling too fast, tungsten strikes, etc). It's not a design issue- its a QC issue and I am sure they will take care of it.

  35. #35
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    Bummer, mine is cracked too!!!

    After reading this post, I decided to inspect my frame in the same area. Oh, crap, I think I have the start of a HAZ crack. I spot checked it with fluorescent penetrant and it bleeds back wipe after wipe. I guess I will continue to monitor it.
    Attached Thumbnails Attached Thumbnails Pugsley frame failure-pugsley-frame-crack-1.jpg  


  36. #36
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    Quote Originally Posted by RockyRider View Post
    Sure it can. While I wouldn't normally preheat or need to stress relieve 4130 this thin if I was welding it, letting it cool too fast after welding (TIG) it then it would become exceptionally brittle right where it's failing.

    These are made in Taiwan right? Not at all out of the question to have a new guy make mistakes like this on a production line (cooling too fast, tungsten strikes, etc). It's not a design issue- its a QC issue and I am sure they will take care of it.
    yeah, but if it was a QC issue, wouldn't it show up in random areas on the bikes?
    if a product fails in one spot every time, when there are welds all over the bike, what are the chances that it's from a fluke mistake welding?

    it's possible there are poor welds all over the bike, but this is the only area that is stressed enough to cause failure, but a good design would be able to handle a little variance in the weld process. If the welds were that bad on QC, it would be apparent elswhere.

    I think it is obvious there is either a weak spot in the basic design, or the tubing spec is too thin right there.

  37. #37
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    Quote Originally Posted by autodoctor911 View Post
    yeah, but if it was a QC issue, wouldn't it show up in random areas on the bikes?
    if a product fails in one spot every time, when there are welds all over the bike, what are the chances that it's from a fluke mistake welding?

    it's possible there are poor welds all over the bike, but this is the only area that is stressed enough to cause failure, but a good design would be able to handle a little variance in the weld process. If the welds were that bad on QC, it would be apparent elswhere.

    I think it is obvious there is either a weak spot in the basic design, or the tubing spec is too thin right there.
    Not if they are using the same assemblers as a multitude of other bike companies. Its an actual assembly line where they make different runs of bikes and chances are it's one person welding that area and then it moves onto somebody else to work on other areas.

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    hmm just checked out my bike again and under a bright LED light I can see a faint line, just like Tripower's pic, but much fainter.. Can't feel it yet with my nail.. I'll keep monitoring it but I assume it will develop into a crack..

  39. #39
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    ^in reference to the green colored frame above^...
    ...a little brass and gas, a metal gusset, and splash of paint later, makes Happy Jack!

  40. #40
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    Surly really did stand behind their product, in less than 2 weeks time I was once again riding my favorite bike this past weekend and had a blast riding it on some of the roughest trails around here, I will be keeping a better eye on it.
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  41. #41
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    Quote Originally Posted by dirtrider6 View Post
    Surly really did stand behind their product, in less than 2 weeks time I was once again riding my favorite bike this past weekend and had a blast riding it on some of the roughest trails around here, I will be keeping a better eye on it.
    great to hear.

  42. #42
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    Quote Originally Posted by boogman View Post
    hmm just checked out my bike again and under a bright LED light I can see a faint line, just like Tripower's pic, but much fainter.. Can't feel it yet with my nail.. I'll keep monitoring it but I assume it will develop into a crack..
    Mine is at the same stage, visible with light but tough to photograph. Not worried, I marked the ends with a sharpie, if it grows past the marks then I'll contact Surly. Chances are it's been like that for months and I never bothered to notice. Surly is good people, they'll take care of it. There have been no reports of complete separation, so it's not really a safety hazard. Minor inconvenience if anything, but I'd be lying if I said I wasn't excited to drink beer and rebuild my bike!
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  43. #43
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    Hey;

    This is not an uncommon failure, and has been seen on many different bikes for many years. There could be a number of reasons for it, both contributory or direct. While it is true that these cracks are appearing in the HAZ, that is most likely only a contributing factor at best. If it happened on an entire sequential batch of frames, in a more consistent pattern, I would be more inclined to believe it was an issue. More than likely, it is not a result of that at all, since it is a fairly widespread failure type, and somewhat random.

    It is most likely from simple fatigue failure. That area sees a lot of stress; from the twisting motion demonstrated in the previous video, from direct compression loading when the rear tire hits a bump, and from seat post stresses. Since those loads cannot be absorbed by the seat tube in bending/twisting over a length of tube because it is directly opposed by the top tube, the stress is put into the material in a very localized fashion. The small stay size also further focuses the stress in a small area. That very particular spot just on either side of the weld bead is also the first portion of tube unsupported by the weld, and so will see magnified stresses.

    It is likely that a redesign of the angles of the tops of the stays, where and how the intersect the seat tube, and the placement and shape of the bridge would solve it.
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  44. #44
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    What is the HAZ?

  45. #45
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    Haz

    Heat Affected Zone

  46. #46
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    Somebody hazn't...

    Quote Originally Posted by boogman View Post
    What is the HAZ?
    ...been following this whole thread!!!

    A good description can be found here Heat Treated 4130 thanks to some race-car aficionados.
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  47. #47
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    Well I read this thread and went out to the garage to check my frame and here is what I found:



    Now what? I'm contacting my LBS who I purchased the bike new from. Hopefully Surly will honor their manufacturer defects warranty. From what I've read, they seem to stand behind their stuff.
    Last edited by ultraspontane; 12-31-2012 at 01:26 AM.

  48. #48
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    Found the same crack on my white Pug. My shop and Surly are standing behind the product and I'll be back on a fat bike in a week or so.

  49. #49
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    HAZ has been covered.. But one aspect of the weld is.. the weld bead itself is usually taller and wider hence stronger/ less ductile.

    This lessening of Ductilitiy can lead to failure just around the weld and is not caused by HAZ but from bad design (uneven stress load)or even a to large weld bead. These look like stress cracks.

    4130 does not like to have stress risers and the lack of ductility simply can cause a stress riser within the tubing itself.

  50. #50
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    Quote Originally Posted by RockyRider View Post
    Yeah I saw that. Also a lot of assumptions being made there about what the cause is that are pretty far fetched.
    the reason is the assymetrical seat stays dont distribute the load eqaully, one is more curved than the other, thus one flexes more and the other remains more rigid

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