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  1. #26
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    Quote Originally Posted by NJfolder View Post
    I totally agree. It seems most everyone who has responded to this post is not seeing how dangerous this type of failure can be. If I went to Walmart and bought a cheapo MTB for $50, I'd expect this type of failure-- but not on a Downtube. Sure, things happen from time to time, but I wonder how often this type of failure has occurred and what Downtube is doing about it, if anything.
    Why do you expect it from a Walmart bike, but not a Downtube? After all, the cheapo folders at Walmart cost about the same as the cheaper Downtubes (especially if you consider the ebay ones).

    Quote Originally Posted by spambait11 View Post
    Quality control? It did not break at the welds. Are you going to blame them for the quality of aluminum as well?
    Why not? Isn't securing decent materials part of the job of building a bike?

  2. #27
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    Load question

    Please forgive my asking, but how much did the rider weigh at the time of the breakage?

  3. #28
    Señor Mambo
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    Quote Originally Posted by makeinu View Post
    Why not? Isn't securing decent materials part of the job of building a bike?
    I'm thinking many here suppose that Yan didn't bother to check. This might be true, and if so, would be very short-sighted on his part, esp. if he's trying to make a name for DT. Another possibility is that the manufacturer could have baited and switched materials. We'll see how this pans out.

  4. #29
    Señor Mambo
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    Quote Originally Posted by gazer View Post
    Umm, yes it did.

    The weld either weakened the metal by using too much heat, or left a space/nick which served as a stress concentrator and led to the failure.

    If their tubes are failing outright, Downtube has a much bigger problem on their hands... And yes, if their aluminum was that bad, I'd blame them for it too.
    You may be right; I take that back.

    What still needs to be determined though is if DT's "tubes are failing outright" or if this is related to how the OP uses the bike. As a fellow commuter, I know how I treat my IXFS esp. now that I don't use public transportation anymore, and enjoy the challenge of getting home as fast as I can.
    Last edited by spambait11; 11-21-07 at 05:44 PM.

  5. #30
    Wheelsuck Fat Boy's Avatar
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    Quote Originally Posted by spambait11 View Post
    Quality control? It did not break at the welds. Are you going to blame them for the quality of aluminum as well?
    If you look at the first picture, you can see that one end of the shear starts at the edge of a weld. It doesn't go _through_ the weld, it starts right at the edge. This is called the 'heat affected zone' (HAZ). I'd bet the farm that this weld was undercut(not enough filler) and that was the initiation point.

    You don't need a problem all the way through the tube....all you need is one 'dotted line' and time will take care of the rest.

    I will say that before this actually broke, I would suspect that there was at least some sort of tell-tale signs going on if the owner would have inspected everything very closely. Probably this would have been more closely than normal. I would also think that there might have been a few seconds of the bike really moving around under the rider before it actually let go. But, since there isn't much bending in the ends of the tubes, it very well might have been a sudden brittle fracture.

    My guess is that you could weld this, gusset the tubes a bit and get a fair bit more time on the bike. It would take a decent fabricator to do it, but they aren't _that_ hard to find. The bike is 6061 AL if I remember right, and that's a very common alloy that is easy to weld. Once it's welded, it will be no stronger or weaker than it was previously (except for the possibility of an undercut weld). The gusseting would made a big difference, though.

  6. #31
    Junior Member Cascade's Avatar
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    Regardless of the warranty limitations this is an obvious defect in materials and/or workmanship and Downtube should provide a new frame. In fact many states do not allow certain warranty limits regardless of what the manufacturer specifies. Downtube would also gain a lot of good publicity, and reroute the negative impacts of this occurence, by helping resolve the issue to the customer's satisfaction.

    BTW I am recovering from a broken left hip and plan to buy a Downtube once I am riding again. So for both of those reasons I am watching this thread very closely.
    Last edited by Cascade; 11-22-07 at 01:19 AM.

  7. #32
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    EvilV - thankyou for posting those pics - worth 1000 words and v sobering.

  8. #33
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    Quote Originally Posted by Simple Simon View Post
    EvilV - thankyou for posting those pics - worth 1000 words and v sobering.
    Well, I was wondering if they were a bit gory and then I thought, maybe not, because THAT is what is at stake if a frame breaks on the road. I ride a lot in an urban environment, I'm usually a foot or two from cars and trucks. I avoid busy fast roads, but while I'm working out at 15 - 22 mph, one, two and twenty tonne vehicles are passing me at 30 or 40 mph, so what happens if a collapsing frame causes me to suddenly deviate or worse still, to fall off?

    “Get a bicycle. You will not regret it, if you live." - Mark Twain

  9. #34
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    I love my Downtube NS-9 and hammer it daily for a 10mile to and 10 from
    commute. Its totally flat here but you can still feel everything flexing like Gumby
    In a hilly situation I suppose this would be even worse. But to be fair, a search using the
    word 'crack' in the Roadie forum would show plenty of hyper-$$$$$ expensive bikes of
    all types of materials crack too.

  10. #35
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    thanks for all the replies, I'm not going to have it welded as I really want to trust whats under me for safety's sake.

    I would say that like a few of the people who replied, i like to ride speedily to and from work. the route is fairly flat and well made, but of course a few jolts have happened. not sure what my weight is as i don't have scales. If your riding style sounds like mine then maybe best to check the seat tube before you ride just in case. it could of course be that i have a duff unit but it doesn't hurt to be careful.

    Barney

  11. #36
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    "If I went to Walmart and bought a cheapo MTB for $50, I'd expect this type of failure..."


    I don't think so. There are ten million lawyers anxiously waiting for just this sort of thing!

  12. #37
    Senior Member Nigeyy's Avatar
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    Well as a Downtube owner (front suspension only) I can't deny I'm a little concerned. Was that frame a non suspension or just front suspension frame? Reason I ask is that the two frames do differ a little with an additional supporting member between the bottom bracket and top tube on the frame with just front suspension. This *might* prevent such a failure....

    Anyway I know that frames do and can fail -even with the best quality control. More worrying would be more instances of this happening compared to the number of Downtubes used in a similar manner assuming usage within the weight parameters of Downtube (don't know how you find that out, but probably the best thing is to compare against the number of bikes sold and assume many of them aren't used as often, but I digress).

    As a side note, when I buy a bicycle -whether from Walmart or any other source -I would not expect a frame breakage under normal usage for at least a couple of years worth of use. If the frame is prone to catastrophic failure, it shouldn't be sold, it's that simple. What's more difficult is ascertaining what "normal usage" is, and what "prone" to catastrophic failure means, what an acceptable timeframe involved is, and what are deemed acceptable limits. Having said that, I bought a Downtube knowing that there was only a year warrantee on the bike -frame and parts. In hindsight with respect to this post, I can't help wondering whether this was prudent.

    Yan, if ever you need to reply to a thread, this is a good one!

  13. #38
    Eschew Obfuscation SesameCrunch's Avatar
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    Quote Originally Posted by Nigeyy View Post
    Well as a Downtube owner (front suspension only) I can't deny I'm a little concerned. Was that frame a non suspension or just front suspension frame? Reason I ask is that the two frames do differ a little with an additional supporting member between the bottom bracket and top tube on the frame with just front suspension. This *might* prevent such a failure....
    I think it's the NS. They haven't made a Front Suspension in black yet. NS is a lighter frame without the bracing, as you said.

  14. #39
    Senior Member JosephLMonti's Avatar
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    Quote Originally Posted by SesameCrunch View Post
    I think it's the NS. They haven't made a Front Suspension in black yet. NS is a lighter frame without the bracing, as you said.
    I have the 2007 (released in June 2006) Front Suspension in black. Also, if you look at the photos of the broken DT, the frame looks more like the Front Suspension than the NS, specifically, the seat tube would extend a lot more beyond the top tube on the NS than the one in the photo.

  15. #40
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    just to confirm, its a black 2007 front suspension model.

  16. #41
    To fold or not to fold?
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    Yan contributes to this forum pretty regularly - I'd be surprised if he hasn't been alerted to this thread. Has he been in contact with you on this? Have you emailed him? If so, what response? This is one DT problem I'd have expected him to be all over (to the extent of getting the bike mailed back to him to inspect). Having been made aware of this pretty serious failure, if he hasn't checked out whether its a more widespread design or manufacturing problem (as opposed to just an unlucky one-off) he could find himself on the end of some pretty toxic lawsuits if any other DT bikes break in the same way and someone gets hurt.
    foldingbikes.wikispaces.com - help create the ultimate folding bike community resource

  17. #42
    Senior Member downtube's Avatar
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    Quote Originally Posted by matt52 View Post
    Yan contributes to this forum pretty regularly - I'd be surprised if he hasn't been alerted to this thread. Has he been in contact with you on this? Have you emailed him? If so, what response? This is one DT problem I'd have expected him to be all over (to the extent of getting the bike mailed back to him to inspect). Having been made aware of this pretty serious failure, if he hasn't checked out whether its a more widespread design or manufacturing problem (as opposed to just an unlucky one-off) he could find himself on the end of some pretty toxic lawsuits if any other DT bikes break in the same way and someone gets hurt.
    Matt,

    I would like to address a couple points. First I want to address this failure issue. Everyone seems interested in trying to determine the cause of this failure. I too am interested in the question, however there seems minimal information given. Rider weight/height has not been defined, exactly how it happened, was there an incident along the line of breakage previously? Ever have a shearing force at that point. Without more information I do not think anyone can make any claims about the bike. However I will agree that calling it defective from the pics and limited information would most likely be the proper judgment.

    Now let me ask another question.....How likely is it that a manufacturer has no frames break? I would think it to be impossible for no frames to ever break by a manufacturer. I have broken two frames, one a Marin, and the other an off brand I can't remember. Does this information imply anything bad about the bikes? Maybe maybe not. It is the beginning point to asking the right questions and understanding.

    Question #1 What is the defect rate of Downtube frames.....assuming this one is defective?
    Answer: Well less than 1 out of a 1000.
    Question #2 Are the frames tested?
    Answer: Yes both by stress testing machines and by real life riding.
    Question #3 Have the frames passed all tests?
    Answer: Yes we have only broken one prototype frame during stress testing, and that frame was changed before production.
    Question #4 are the current frames the same?
    Answer: No there were some changes in 2008 to accommodate taller riders.
    Question #5 Will the frames stay the same?
    Answer: We have plans to change most of our lineup every year. As we have in the past.

    Again I think the claims of our bikes being compared to Walmart bikes are a little premature.

    This is the first I have heard about this problem, and I do not think it is proper for me to deal with it in a public forum. We handle many warranty claims every year, all are discussed privately. Hence I would prefer to do the same here.

    I think we have a quality product with minimal defects and we have many customers that feel the same. FYI if our defect rate was high we could not sell our bikes for the prices we do. Our low problem rate make our business model feasible.

    Several writers have mentioned that they were surprised I have addressed this issue before. I have stopped coming to the forums as frequently and will probably not attend as much in the future. In 2005/2006 I had a great time here....lots of fun & friends. Many of the old friends have moved on & several other members have used the forum to attack me. In short it is not as much fun as it was and I do not think I will be as active for a while. Hopefully it becomes fun again for everyone....why else would we all be here???

    Thanks,
    Yan

  18. #43
    Bicycling Gnome
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    Well said.

    The Downtube bikes were never Walmart bikes, else they would never have had the reception they have had here. It seems to me that DT have produced some innovative cycles and given a lot of people pleasure for not a lot of money. They seem far and away in the bracket of 'best value' - not the cheapest, but far and away a better buy than many other low cost models. So they don't have top class componentry - well, if you want a lot of Campagnalo and other expensive makes, go out and pay through the nose for no more functionality.

    I can buy a 2007 Mini here in Britain with all taxes paid ($190 tax and shipping) for an all in cost of £286. There is no decent folder here for ANYTHING like that, and that includes my beloved Merc which is £330. I have no doubt that the mini is the equal of that at least.

    As for Matt's mention of law suits - what a bizarre idea. Everyone who ever gets on a bike knows that they take their life in their hands every time they do. We all want lighter and lighter bikes and any poster here knows that metal fatigues, especially aluminium. So who are we going to sue if a bike breaks? Personaly, I wash and minutely examine each of my bikes every hundred miles and on the ally ones - which is most of them, I look extremely carefully at the paintwork, especially around joints. I've never had a problem, but I'd count myself a fool if I rode a bike mile after mile knowing that ally frames let go occasionally and hadn't checked them out at known trouble spots on a regular basis.
    “Get a bicycle. You will not regret it, if you live." - Mark Twain

  19. #44
    Lonesome No More nigelme's Avatar
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    You have to take rough with smooth; surely this forum is a feedback arena for 'real world' experience of 'real bike users' and hopefully for manufacturers. It's a pity that Yan doesn't want to hear the negative because it isn't fun. I read these threads to hear when things go wrong as-well as right.

    I have a Downtube IX FS; I got it partly because of what I read on this forum and I will still buy a DT Mini (when shipped to UK). This one frame failure hasn't totally tarnished the brand. It has made me think about checking my 'stress lines' occasionally, so it's been useful. Of course if my frame failed i'd never buy that brand again so erm! (things that happen to me have more impact!)

    The bike mechanic who set up my DT reckoned the frame was stronger and better engineered than many other folders he's worked on - so - what?

    Where can I get a Walmart bike in the UK? (only joking)

  20. #45
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    Quote Originally Posted by nigelme View Post
    It's a pity that Yan doesn't want to hear the negative because it isn't fun. I read these threads to hear when things go wrong as-well as right.

    Where can I get a Walmart bike in the UK? (only joking)

    But, realistically, how many people chime in
    with negative stuff on any given multi-page
    thread that are just opining with no first hand
    knowlege of the product, as in, I wonder what the
    ratio of real Downtube owners to opinionaters is
    in the loooooong, ongoing Downtube thread ?
    If I was a manufacturer my patience would wear
    thin too....To its benefit, this is a friendly forum
    compared to alot of the other ones, though.

    Also, WAL*MART is soley responsible for the decline of our society...
    You really dont want one there

  21. #46
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    A couple of things bothered me in this thread: The OP has no idea of his weight because he has no scales? Hmmm. What did I weigh the last time I checked? Was it 375? No no, silly me, it was 175.

    The other is the shear point in the pics makes a lot more sense if that was where the saddle post ended. I know he said it was waaaay down further but the OP is the calmest guy in the thread, no evident anger, just willing to trash his 1.5 yr/old frame and move on. I'd like to see a pic of the post itself. Mine shows where it's insertion point is.

    I'm all for open info but I'd bet a case of beer that the OP would have had a new frame on the way if he'd have handled this privately as Yan suggested. As others have said, bike frames do break. That breaking near the weld stuff was scary but we all know it happens. Given the compactness of folders, maybe our frames are stronger than larger bikes. I used to crew on an offshore aluminum dive boat. Things broke all too frequently. They got welded back together before 6 am next day.

  22. #47
    Bicycling Gnome
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    Quote Originally Posted by nigelme View Post
    Where can I get a Walmart bike in the UK? (only joking)
    ASDA sell bikes sometimes, though I haven't been there in a while. Asda is walmart as you probably know. A few years back I saw some bikes in ASDA for £68 - chunky looking mountain bikes. I think they may have been steel frames. I bought two for my teenaged sons and they had teh wheels trashed within a week. I took them back and got my money back. They were a bad buy.

    Isn't the mini here in the UK? The DT site seems to suggest I can get one here. Maybe I missed something. I was tempted now the dollar price makes it so attractive. The mini has had some VERY enthusiastic reports on here - almost universally 'joyous'.
    “Get a bicycle. You will not regret it, if you live." - Mark Twain

  23. #48
    Senior Member staehpj1's Avatar
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    Quote Originally Posted by tgzzzz View Post
    I'm all for open info but I'd bet a case of beer that the OP would have had a new frame on the way if he'd have handled this privately as Yan suggested.
    That was my thought as well. I have found that talking to the manufacturer or distributer often will get a fix even if out of warranty. IMO: Complaining online is a bad idea unless you have exhausted all of your possible remedies first.

    In this case it didn't seem like the OP thought he had or should have had a chance of getting any resolution from Downtube. I think that is often a mistake. Most companies want to have satisfied customers. If they can't see clear to replace the part in question sometimes they make other concessions like a deep discount on a replacement for the broken part.

    I know that I have had great service from several companies in this regard and it tends to make me more loyal to their product. I am more likely to buy again and also to recommend the product to others.

  24. #49
    Eschew Obfuscation SesameCrunch's Avatar
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    Quote Originally Posted by downtube View Post
    Several writers have mentioned that they were surprised I have addressed this issue before. I have stopped coming to the forums as frequently and will probably not attend as much in the future. In 2005/2006 I had a great time here....lots of fun & friends. Many of the old friends have moved on & several other members have used the forum to attack me. In short it is not as much fun as it was and I do not think I will be as active for a while. Hopefully it becomes fun again for everyone....why else would we all be here???
    I, for one, am sorry to see Yan retreat from the site. It was great to have the owner of the company "talk" directly with the customers. I think it's been good for us and good for him as well.

    Unfortunately, I can sympathize with his point that this path has been overused and perhaps abused.

    Oh well, all good things eventually come to an end. RIP...
    Last edited by SesameCrunch; 12-05-07 at 09:10 AM.

  25. #50
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    More info better than less

    Quote Originally Posted by tgzzzz View Post
    I'm all for open info but I'd bet a case of beer that the OP would have had a new frame on the way if he'd have handled this privately as Yan suggested. As others have said, bike frames do break.
    Privately may have worked better for him, but getting the information out is better for us. This is only one frame break in thousands, and I think informed customers can see that--especially with the great analysis on this board-- but it is important to get the information out there in case there is a larger problem.

    A frame break was brought to light publicly in the Swift forum and I believe it ended happily, with the owner getting a new frame, and showing pictures of the frame design changes Xooter made (which may not be necessary in this case).

    BTW, I finally convinced my girlfriend to take the plunge and get a foldie, and am still seriously looking at the Mini. I'm going to have her test ride it at the NYC spring foldie ride if one's available.

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