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  1. #1
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    EQ23 is flexy.. I dont think it was before.

    Same wheel, same bike ive had for a couple years now.

    Last ride I noticed something a little funny going on in the rear over certain features. The rear wheel feels flexy. Ive never noticed a flexy feeling out back before, its always been pretty solid. Im almost 30lb lighter than last year, and I never felt it last year. Pivots are tight, no bearing slop, no frame cracks.

    Pulled the wheel and checked tension, its even enough, adjusted the dish a little. Heres the weird part... when I stress relieved it and trued it up I realized I could flex the wheel enough in my lap to fully detension the spokes, on both the ds and nds side. I might be able to taco this thing by hand! Its just plain flexy. Ive built a lot of road wheels, and none have been this flexy, despite narrower spacing and taller rims.

    Is it possible that the pinned joint came loose and is contributing to flex? A rim shouldnt just lose stiffness, it doesnt make a lot of sense.

  2. #2
    Save Jesus
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    spoke tension too low

  3. #3
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    125kgf on the DS.

  4. #4
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    Too much spoke tension then, LOL.

    It is possible, but unlikely, that if the 125 kgf includes an inflated tire, that the rim is nearing the radial collapse point (although it is technically not radial collapse but a taco collapse due to conservation of [technical stuff snipped]). This is related to the Jobst Brandt spoke tension test of "do a stress relief, and if the rim starts to taco, you have too much tension and need to back off". My guess is that you tried to bend the wheel into a taco, i.e. push the hub one way and pull on both sides of the wheel. This is exactly the kind of load to apply to a wheel if you want to taco it, and also unlike the load a wheel experiences during normal riding. If you want to test normal riding loads, mount the wheel in a bike with a rigid rear triangle and using one hand, squeeze the rim towards the chainstay. Doing this on my bike, I get about 3/16" for a firm squeeze, and the spokes lose about 1/2 the tension on one side and gain on the other. The way to differentiate an imminent collapse from a normal reaction to a side load is to see to what extent the neighboring spoke increases its tension.

    More likely, what you are feeling is tire flex and not wheel flex because a tire flexes a lot more, as 4slomo mentioned in another thread. This rim is a scrawny 16mm internal width, and coupled with a big tire, it is going to squirm a lot.

    A loose rim joint is not going to affect the stiffness of the rim because that joint was only for positional alignment and not a brace. An you don't need a brace there anyway because the two ends are held parallel with an incredible amount of compression force.

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