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Discussion Starter · #1 ·
What do you suppose a wheel that had spokes held captive on both sides of the rim would ride like? Currently, it's the spokes above the hub that are under load, while those pointing towards the ground do effectively zero work with on-axis loads (the spokes being free to extend into the rim when the rim is compressed by contact with the ground). Could this configuration be run with substantially lower spoke tension given that the spokes would be under load both above and below the hub? Or would it simply result in more broken rims?
 

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Are you referring to the style BMW used on the 1200GS. The spokes were at the Beed allowing them to have a solid rim and run a true tubeless radial tire.



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Discussion Starter · #3 ·
I can't tell from the photos. The configuration I'm thinking of would essentially require a nipple that had a set of external threads (in addition to the existing internal threads)on the portion that extended through the rim towards the hub, and some sort of nut threaded onto it and snugged up against the rim itself.
 

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I think I follow you. Essentially the spoke tension would be a 0. The pressure on the rim would be taken up by the external nut on the spokes. It's an interesting thought. It may add a lot of complexity to a simple system.

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Spokes have essentially no compressive strength as they'll just bend. You can find videos and pix of wheels under load that show the lower spokes bending despite not being captive.
 

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Discussion Starter · #7 ·
What is it that compresses those bottom spokes? There's absolutely nothing that prevents the nipple with the spoke attached from simply moving into the rim when the rim is pushed towards the hub. The bike actually hangs from the upper spokes under tension.

For your contention to be true, there would have to be something that keeps this from happening, as would be the case in the hypothetical design I asked about in the first place.
 

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One Pivot is just trolling. There were some mechanical engineers a while back that argued the fallacy that less tension relative the rest of the spokes = compression.

It's just a schoolboy sophistry. If spokes were really in compression then buckling would be a possible failure mode. But it isn't, because they aren't.

But please, lets carry this on while going in circles for five pages.
 

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One Pivot is just trolling. There were some mechanical engineers a while back that argued the fallacy that less tension relative the rest of the spokes = compression.

It's just a schoolboy sophistry. If spokes were really in compression then buckling would be a possible failure mode. But it isn't, because they aren't.

But please, lets carry this on while going in circles for five pages.
It's measurable though.

Have someone sit on the bike and check tension on the top spokes. Marginal change. The bottom have a drop in tension, due to compression .

We don't see it often with decent parts. You certainly can buckle spokes. Walmart bikes do it fairly easily. Tension drops to zero and the nipples unseat.
 

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You are still being intentionally confusing. Lesser tension != compression.

If you are genuinely uncertain, you are free to peruse the dictionary and refresh yourself on the meaning of these words.
 

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And you can measurably reduce tension by applying _______. :lol:

I agree the whole thing is silly mental masturbation, *until* you start trying to pull a mavic and literally reinvent the wheel. Call it what you will, the bottom few spokes drop tension, but still maintain tension.
 

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And you can measurably reduce tension by applying _______. :lol:
an axial force. That is not anywhere near -

"The bottom 3-6 spokes stand in compression holding up the weight of the bike and rider. "

Glad to see you gave it up.

I'm sure we'll have one of those engineers chime in, the type that make a living baffling with bs instead of being clear.
 
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