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On a scale of fixeable to Dimond how fucked is my bike

doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM
Just riding along on the weekend and noticed my front derailleur wouldn't shift into the big ring. It was almost as if the cage separated and wasn't pulling the chain. I stopped to assess and noticed the epoxy holding my front derailleur mount to the frame had come away and also pulled the rivet through the carbon. It's a 2010 Scott Plasma, Scott's website says frame warranties are 5 years. It's also second hand. I've reached out to the original owner to see if he has the original receipt, and then I'll try and contact Scott to see what they can do for me.

Apart from that, what's anyone elses take on this? I was going to drill out the rivets, remove the mount and assess the damage more closely but I'd rather not do that until I hear from Scott. To me it's a clear manufacturers defect. There's no sign of any corrosion on the rivet. To me it can either be two things, improper installation of the rivet which wasn't brought to light because the epoxy held, or delamination/corrosion of the carbon/aluminum intervace causing the rivet to pull through.

I found a few articles online with similar issues on other bikes with how-to's on repair. Basically re-riveting with a larger/different type of rivet. My other issue is, and I won't know until I inspect it, is more delamination of carbon around that area. Simply re-riveting and re-epoxy will still leave the underlying problem of delamination, if that's what caused it.







Comments

  • Options
    MartinMartin Member, Rooster Endurance Member
    You might find this page helpful: SRAM Force 1.

    (Thank you for reinforcing my fear of all that is carbon on bikes.)
    MattdhrKenElPescadoPeladoKuchtoebutt769Aaron Webstey
  • Options
    scottyscotty Member
    It looks like one of those things that's fixable just probably not by you. Lots of carbon repair places should be able to make it work though.

    Is the down tube a funky shape? Wondering if a clamp on hanger would be a cheap/temporary fix.
    ______


  • Options
    doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM
    Martin said:

    You might find this page helpful: SRAM Force 1.

    (Thank you for reinforcing my fear of all that is carbon on bikes.)

    It's funny, because I was thinking about going 1X with this but wanted to use my road bike wheels interchangeable. I'd need to get a larger range cassette if I go 1x. That's definitely an option I'm willing to explore, but to do that I'd have to invest in some new parts including upgrading to 11-speed which I'd rather not do yet.
    Martin
  • Options
    doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM
    edited May 2017
    scotty said:

    It looks like one of those things that's fixable just probably not by you. Lots of carbon repair places should be able to make it work though.

    Is the down tube a funky shape? Wondering if a clamp on hanger would be a cheap/temporary fix.

    It's a funky shape with the rear wheel just a few MM from the seat tube, so no chance of fitting a band-on hanger. I have a little experience with carbon repair, and know a few people. I saw this blog post which looked encouraging http://roguemechanic.typepad.com/roguemechanic/2012/01/shimano-di2-front-derailleur-1-felt-f1-front-derailleur-mount-0.html , but I also saw a post from a pro carbon repair specialist that had the same issue and the entire seat tube needed to be cut out, repaired, repainted, etc.

    I think it's more of a case of "it can be repaired correctly and never be an issue again by someone else, or it can be hacked and have a 75% chance over never being an issue if i do it"
  • Options
    KHilgendorfKHilgendorf Member, Rooster Endurance Member, POTM
    Do the repair yourself and have 1x as a backup plan. All you truly need is to pull the FD and small ring, but you might want to add a narrow wide to be safe. 1x10 is fine. You don't have to get all new parts.
    Martin
  • Options
    Zach MillerZach Miller Member, Rooster Endurance Member, POTM
  • Options
    PevashishDaulPevashishDaul Member, POTM
    Pressure them into a voluntary recall.
    Aaron Webstey
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    scottyscotty Member

    Pressure them into a voluntary recall.

    1. File suit against them
    2. Start a GoFundMe to cover costs.
    3. Post to Slowtwitch.
    4. ?????
    5. PROFIT!!
    KenElPescadoPeladodoyoueventribroMartinsimonsen77DawnCTad_MHSeeley14Aaron Webstey
    ______


  • Options
    wchevronwchevron Member, POTM
    6. Return all GoFundMe money, tell everyone you really just wanted to find out how much everyone liked you.
    KenElPescadoPeladoscottySeanHMartinM_Waretoebutt769DawnCkjrunninTad_MHSeeley14Aaron Webstey
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    doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM
    edited May 2017
    I took a better look at the damage. The hole seems fine and there's no audible "dull" sound when I do a coin test. It looks like the rivet was the issue.

    I think the main failure, however, is the design. The derailleur hanger is only mounted using two small 1/8" rivets, one of which wraps around the seat tube and connects on the edge (the one that pulled out).

    The mount, and derailleur, wants to be straight, because, but the rivet it forcing it closed. I think even if I repair it identical to new the same issue could come up in the future.

    The option I'm exploring now (unless Scott decides to warranty the frame) is to use a different derailleur mount. Basically I'll remove the old mount and use a different one. One that doesn't apply force on the edge of the seat tube, like this. http://soshanger.com/epages/box11137.sf/en_GB/?ObjectPath=/Shops/box11137/Products/"WG39/GNT"

    To do this, I'm not sure if I should build up an extra layer of carbon or not. It's easy enough to fill the old holes with some epoxy but I'm not sure how built up that area is. If I go with a new mount there's a possibility that the new holes will also pull out which could be catastrophic since it would basically pull away the carbon with it. Adding some extra carbon is probably the safest route to prevent this but is a lot more time consuming. The other issue is that most derailleurs don't use the standard rivet system, they screw into a rivnut mounted in the frame. Right now I don't have the tools so install a rivnut, but I can work that out. The bonus is that the area for repair doesn't have any decals/paint so once completed it should look like new. I'll keep everyone updated.

  • Options
    MartinMartin Member, Rooster Endurance Member
    You might be the first triathlete to look for ways to NOT buy a new bike.
    simonsen77doyoueventribroStruangKenElPescadoPeladoscottykjrunninSeanHBrent_RTad_MJJacksonHSeeley14Craig_DAaron Webstey
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    KHilgendorfKHilgendorf Member, Rooster Endurance Member, POTM
    @doyoueventribro discounting the idea that the original design is flawed, I'd still try to repair and return to original. As you said, any new holes in that area could be catastrophic. BB shells are very sturdy, but the tubes are usually a lot thinner, especially the seat tube as it doesn't have the same torsional forces on it the others - mostly axial. Which is good both good and bad. It means the bike could still be rideable with a crack in that area, but also that the tube will be more prone to breakage as you drill into it.

    Also, if you do have a failure of your repair on the original clamp design, you still have the 1x back-up. If the re-design fails, you're probably looking at a new frame.
    KenElPescadoPelado
  • Options
    doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM

    @doyoueventribro discounting the idea that the original design is flawed, I'd still try to repair and return to original. As you said, any new holes in that area could be catastrophic. BB shells are very sturdy, but the tubes are usually a lot thinner, especially the seat tube as it doesn't have the same torsional forces on it the others - mostly axial. Which is good both good and bad. It means the bike could still be rideable with a crack in that area, but also that the tube will be more prone to breakage as you drill into it.

    Also, if you do have a failure of your repair on the original clamp design, you still have the 1x back-up. If the re-design fails, you're probably looking at a new frame.

    Good point. I think I'll scrap the redesign unless I find some legit carbon damage. I think just replacing the standard blind rivet with a flange rivet/bulb rivet should do the trick. The trick is that, because of the design of the mount, I can't use a larger head rivet, so even slight damage to the hole might mean I go with the redesign
  • Options
    doyoueventribrodoyoueventribro Member, Rooster Endurance Member, POTM
    Great news for anyone that gives a shit about some age groupers 7 year old bike. I drilled out the rivets and it looks like there's absolutely no damage to the carbon. I'm taking it into a bike shop on the weekend to use their scope-camera-thing but from the outside it looks like the rivet just failed. Most likely from the excessive amount of epoxy that was used. Fuck 1x drivetrains (for now)





    balsdorfKenElPescadoPeladoMattsimonsen77Tad_MCraig_DMartin

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