Forum home Road cycling forum Workshop

Bent Aluminium Seat Stay.

dafyddllywelyndafyddllywelyn Posts: 9
edited May 2015 in Workshop
Yesterday I finished a 104 mile sportive, and just after the finish line upon seeing someone I know I slowed down. Then another rider crashed into the back of me. The resulting crash seemed innocuous at first, with me having a bent spoke and broken (cheap) bottle cage, so just shook hands and thought none of it.

Today, having sorted both of those problems at the workshop. I noticed that there was a bend in the seat stay, one at the dropout and another half way up the seat stay (on the chainstay side.)

I've included a picture, does it need repairing? Can it be repaired?

The seat stay does have a graze on it from a failing to clip out incident a few years ago, and seems to show that it's solid as opposed to hollow... don't know if this makes any odds though!

Should I chase up this fellow who went into the back of me, or is that being petty?

Posts

  • Sad to say that looks terminal. The kink is in the worst place for stress and I think it will compromise your safety if you ride it. I'd put it down to experience and start the exciting process of choosing a new frame.
  • dnwhite88dnwhite88 Posts: 285
    edited April 2015
    +1 unfortunately that looks fit for the bin

    EDIT as far as finding the chap responsible goes, I think by shaking hands at the scene you forfeited any right to a claim there, assuming he was liable which if you slowed without warning is surely debatable?
    "It never gets easier, you just go faster"
  • BTW the seatstay will be a tube not solid.
  • keezxkeezx Posts: 1,311
    I would carefully bend it back straight and observe what happens while and after riding.
    Seatstays are only loaded on pressure and besides that, there are frames with bent seatstay on purpose which last.
  • censored ... was afraid so.

    Tbh, the end of the event was a bit of a blur, also the thing with the frame wasn't noticed so not sure. But he'd certainly have a case to say that i stopped a little earlier than would be expected. Also difficult to estimate the value of a four and a half year old aluminium frame, certainly under a £100.
  • imposter2.0imposter2.0 Posts: 10,825
    keezx wrote:
    I would carefully bend it back straight and observe what happens while and after riding.
    Seatstays are only loaded on pressure and besides that, there are frames with bent seatstay on purpose which last.

    Seriously, please ignore this advice.
  • Imposter wrote:
    keezx wrote:
    I would carefully bend it back straight a... are frames with bent seatstay on purpose which last.

    Seriously, please ignore this advice.

    Not to worry on that one! Almost seemed sarcastic.
  • Smokin JoeSmokin Joe Posts: 5,669
    keezx wrote:
    I would carefully bend it back straight and observe what happens while and after riding.
    Seatstays are only loaded on pressure and besides that, there are frames with bent seatstay on purpose which last.
    :shock: :shock: :shock: :shock: :shock:
  • dgunthordgunthor Posts: 644
    +1 frame for bin (keep the forks!)
  • apreadingapreading Posts: 4,534
    I would bin it. I think you could get it repaired but the cost and hassle probably wouldnt be worth it (http://www.allmetalweldingservices.co.u ... airUK.html for example).

    I wouldnt consider riding or fixing it yourself though.

    You would still have a case to go back to the guy that hit you - legally anyway, morally I can understand why you would feel that you let it go and its awkward to pick up with him now.
  • Right... A bit of luck, a friend of mine who works restoring a rebuilding (very) classic cars is going to have a look and take it to his boss. So my thoughts are if anyone can fix it it'll be them.

    Yeah, it's the moral quandary of chasing up a cyclist for an honest mistake. I think I might make a decision once I know the deal with the frame.
  • imposter2.0imposter2.0 Posts: 10,825
    Don't bother trying to repair, it's not worth it. The stay will have work hardened and bending it back will weaken it further. Replacing the stay (if you can find a replacement) will almost certainly require the frame to be heat-treated again. Bin it and move on.
  • Imposter wrote:
    Don't bother trying to repair, it's not worth it. The stay will have work hardened and bending it back will weaken it further. Replacing the stay (if you can find a replacement) will almost certainly require the frame to be heat-treated again. Bin it and move on.

    Totally agree, more effort than it's worth and uncertain outcome.
  • keezxkeezx Posts: 1,311
    Imposter wrote:
    keezx wrote:
    I would carefully bend it back straight a... are frames with bent seatstay on purpose which last.

    Seriously, please ignore this advice.

    Not to worry on that one! Almost seemed sarcastic.

    No I'm dead serious.
    When no cracks appear after bending it 'll be fine.
  • QubeQube Posts: 1,899
    keezx wrote:
    No I'm dead after riding with a dangerously bent seat stay.

    FTFY.
  • GiraffotoGiraffoto Posts: 2,078
    That's busted, and I'm afraid you're morally obliged to accept it as One Of Those Things. The only way to make yourself feel better is to get a shiny new bike, or at least a shiny new frame.
    Specialized Roubaix Elite 2015
    XM-057 rigid 29er
  • Monty DogMonty Dog Posts: 20,614
    If the frame alignment isn't seriously out of whack to affect handling, then you could probably carry on riding it - but it will probably crack sooner or later - just be prepared for the taxi ride home!
    Any notion that you could bend it back is nonsense - written by someone who has never worked with metal is my guess.
    The same for a repair - welding thin alloy tubes is tricky and the welding will probably create local stress raisers due to heat or changes in section - it'll probably last no longer than riding the bent frame.
    Make mine an Italian, with Campagnolo on the side..
  • keezxkeezx Posts: 1,311
    I can cut my seatstay in 2 with a grinder and wrap it with ducttape and ride on.
    BTW I'm a licenced welding technologist, so I know averything I need to know.
    Even hardened aluminium alloy has some working space, it's not 100% brittle as some believe....
    Trying does'nt harm anyone.
  • keezxkeezx Posts: 1,311
    Qube wrote:
    keezx wrote:
    No I'm dead after riding with a dangerously bent seat stay.

    FTFY.

    Some people should stay away completely from bikes, far too dangerous.
  • Surely the important point here is that the op has the perfect reason to justify an N+1 - what else is there to discuss?
  • apreadingapreading Posts: 4,534
    This can be fixed but not many people know how to work with Aluminium. The link I attached earlier and others I found with a brief google shows people who do this and know what they are doing. Even carbon can be repaired.

    Its all about the cost and hassle of finding/visiting/posting to a professional that normally rules it out though.
  • gozzygozzy Posts: 640
    apreading wrote:
    This can be fixed but not many people know how to work with Aluminium. The link I attached earlier and others I found with a brief google shows people who do this and know what they are doing. Even carbon can be repaired.

    Its all about the cost and hassle of finding/visiting/posting to a professional that normally rules it out though.

    Carbon certainly can be repaired. A friend bought a colnago c59 with a snapped chain stay for not very much money, he also bought some carbon sheets to wrap it and now has a working c59.
  • GiraffotoGiraffoto Posts: 2,078
    apreading wrote:
    This can be fixed but not many people know how to work with Aluminium. The link I attached earlier and others I found with a brief google shows people who do this and know what they are doing. Even carbon can be repaired.

    Its all about the cost and hassle of finding/visiting/posting to a professional that normally rules it out though.

    From my scant knowledge of the subject I'd actually expect carbon to be easier to bring back up to full strength than aluminium.

    Just to fly off at a tangent for a moment, I used to have a steel frame, and I had to get it repaired. Despite the oft quoted "steel is better than aluminium or carbon because you can get it repaired", it's still a massive hassle and you still need a full respray at the end of the process. So whatever your frame material, if you bust it your bike's still going to be OC for a month.

    And to the OP: get a shiny new frame.
    Specialized Roubaix Elite 2015
    XM-057 rigid 29er
  • imposter2.0imposter2.0 Posts: 10,825
    apreading wrote:
    This can be fixed but not many people know how to work with Aluminium. The link I attached earlier and others I found with a brief google shows people who do this and know what they are doing. Even carbon can be repaired.

    Its all about the cost and hassle of finding/visiting/posting to a professional that normally rules it out though.

    Carbon can be repaired. But there is no correlation between repairing carbon and repairing aluminium, so it doesn't follow that just because one is economically repairable, the other is too.
  • homers_doublehomers_double Posts: 6,442
    Imposter wrote:
    keezx wrote:
    I would carefully bend it back straight and observe what happens while and after riding.
    Seatstays are only loaded on pressure and besides that, there are frames with bent seatstay on purpose which last.

    Seriously, please ignore this advice.
    keezx wrote:
    I can cut my seatstay in 2 with a grinder and wrap it with ducttape and ride on.
    BTW I'm a licenced welding technologist, so I know averything I need to know.
    Even hardened aluminium alloy has some working space, it's not 100% brittle as some believe....
    Trying does'nt harm anyone.

    Seriously... No.
    Advocate of disc brakes.
Sign In or Register to comment.