Broken spokes mystery???

stefano
stefano Posts: 254
edited July 2008 in Workshop
I have build last March a wheel with Formula hubs CXP22 rims and ACI black double butted spokes. Over the last 4 weeks I had 3 broken spokes. All in the rear wheel and brake just after the nipples.

Any idea what’s wrong?
:? :? :? :? :?

Comments

  • NervexProf
    NervexProf Posts: 4,202
    stefano wrote:
    I have build last March a wheel with Formula hubs CXP22 rims and ACI black double butted spokes. Over the last 4 weeks I had 3 broken spokes. All in the rear wheel and brake just after the nipples.

    Any idea what’s wrong?
    :? :? :? :? :?

    Stefano...were the breakages at a common part of the rim?

    Unusual to have breakages at the nipple end - drive side, or non drive?

    Brass, or alloy nipples?

    Guessing here..but there is a hint of 'dodgy' spokes, at the threaded end - a pic would help to nail it down.
    Common sense in an uncommon degree is what the world calls wisdom
  • chriskempton
    chriskempton Posts: 1,245
    Were the spokes long enough i.e. all the threaded part inside the nipples? As Nervexprof says, it's very unusual for spokes to break at the nipple end, sounds like a definite issue and not just bad luck.
  • stefano
    stefano Posts: 254
    I do not remember for all three broken spokes which side of the wheel...but second one (maybe first one also) was from drive side.
    I think they are the basic brass nipples. I am lacing 3x...
    The spokes brake at the start of the thread that is just inside the nipples.
    I have now replace the spoke...so I cannot take a picture...

    I am thinking to retention the spokes a bit tighter... :?: :?:
  • robbarker
    robbarker Posts: 1,367
    This normally happens when the spoke enters the nipple at an angle and is most common with wheels built with large flange hubs and/or non side-specific eyelets. It can also happen with an incorrect spoking pattern for the number of spokes used. You say you've laced cross 3 - is this a 32 spoke or 36 spoke wheel? if it's a 28 it should be cross 2 to lessen the spoke/nipple angle.

    The solution is to make sure you have an appropriate lacing pattern and then loosen and re-tension all the spokes as if building from new. Make sure you get enough tension in the spokes - loose wheels get looser with use, a tight wheel will last.
  • nicklouse
    nicklouse Posts: 50,673
    to add to the above, the spokes are going to the correct eyelet?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown

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