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Repairing buckled Ksyrium SL rim

ClaudeHClaudeH Posts: 78
edited March 2015 in Workshop
I managed to ride over a massive pothole this morning which punctured my back tyre and also slightly buckled the rear rim. It is not a major buckle, the wheel still rotates true but there is a noticeable "bump" on the rim which is very obvious when braking.

I would welcome opinions on my options. Also, I know I can't keep it like this but should I ride it at all? I am obviously concerned if the slight buckle increases the chances of a complete sudden failure.

Claude

Posts

  • trailflowtrailflow Posts: 1,311
    Any Pictures ?
  • It depends.

    If the shoulder of the rim is bent, then it can be gently bent back in position by means of an adjustable spanner, although it might crack in the process if there is a damage inthe alloy. If the rim is flattened, then there isn't much you can do and realistically you need a new rim or more likely a new wheel.

    Being a rear wheel there isn't much risk in riding it... just avoid bombing at 40 mph downhill
  • Attempted photo
  • keef66keef66 Posts: 13,123
    I've had dings like that several times on my elderly RS10's and successfully bent them back with a large adjustable spanner. Not perfect, but it feels OK under braking which was the objective. One was quite nasty and needed a bit of work with a file to smooth a jagged edge next to the tyre.
  • So I assume the procedure is to take the tyre off, put whole rim into the jaws of an open spanner and gently tighten the spanner, hopefully bringing the bad side into true whilst not damaging the good side?
  • keef66keef66 Posts: 13,123
    Tyre and tube off, yes.

    I just clamped the jaws of the spanner on the buckled side of the rim then used the leverage of the handle to gently bend it inwards again.

    Don't think you can use the spanner like a vice.
  • ClaudeH wrote:
    So I assume the procedure is to take the tyre off, put whole rim into the jaws of an open spanner and gently tighten the spanner, hopefully bringing the bad side into true whilst not damaging the good side?

    No, you only clamp the bad side in the jaws of a spanner and gently bend it back
  • crikeycrikey Posts: 362
    I'd be tempted to use a block of wood and the gentle application of force from a hammer to straighten that, I think you'd have a better chance of ending up with a flat surface if you did it that way. Make sure the wood extends past the bump by a good few inches either side.

    I am not a doctor...
  • Thanks for all the advice. I will give it a go later and report back. If it doesn't work I will be asking for opinions about new wheels!
  • Monty DogMonty Dog Posts: 20,614
    You'll need to bend the rim inwards a touch more than needed in order to get it to deform - better to have a slight depression as an outwards kink will rub the brake which is annoying and wear-out the rim more quickly. Using a hammer will more likely result in too much force and a crack - you can be more progressive with a large adjustable spanner
    Make mine an Italian, with Campagnolo on the side..
  • Hi, it depends how comfortable you will be descending at high speed in the future.

    This is a critical area and if the rim or bead fails then you could be in trouble.

    You might feel ok if you can restore a normal profile. It might last for years. But I would scrap it because it is alloy and has had a big ding and you will at risk to yourself and anyone riding behind you. Shame it is a pricey rim.

    Regards

    Alan
  • Hi, it depends how comfortable you will be descending at high speed in the future.

    This is a critical area and if the rim or bead fails then you could be in trouble.

    You might feel ok if you can restore a normal profile. It might last for years. But I would scrap it because it is alloy and has had a big ding and you will at risk to yourself and anyone riding behind you. Shame it is a pricey rim.

    Regards

    Alan
    Ignore this. It is a small ding and, juddery brakes aside, the rim will be fine.
  • mamba80mamba80 Posts: 5,032
    I have successfully repaired almost identical damage using a vice, it is easier to control, allows for finer "adjustment" I then used a file to take out any slight imperfections, used some hard wood in the jaws as well.
    the rim I repaired was a Kinlin 200 and we ve had zero problems with tire mounting, rim cracking or brake judder.
  • deswellerdesweller Posts: 5,175
    While you're at it, the other thing you want to do is check the spokes in that area...if the rim has bent radially as well as laterally then you might have loose spokes.
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  • keef66keef66 Posts: 13,123
    DesWeller wrote:
    While you're at it, the other thing you want to do is check the spokes in that area...if the rim has bent radially as well as laterally then you might have loose spokes.

    Very good point. My last pothole incident (night ride, blinded by oncoming dickhead with lights on main beam) resulted in a bigger ding than this and some wheel truing was required.
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