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EAT MORE GRIME
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How can these build a wheel as stiff as one built with stainless steel?
they cannot be as stiff

but it is largely irrelevant, wheel will stay centered, just feel a tad more forgiving
 

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Formerly of Kent
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Lightweights are some of the stiffest wheels made (and most expensive) and they use a carbon/Kevlar spoke.

I see no reason these can’t be as stiff as a steel spoked wheel.


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Lightweights are some of the stiffest wheels made (and most expensive) and they use a carbon/Kevlar spoke.

I see no reason these can’t be as stiff as a steel spoked wheel.


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I can't read German. If they use carbon in their spokes, carbon is stiffer than steel; kevlar not.
 

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RAKC Industries
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You realize spoke material means absolutely nothing in that regard right? Its all about the tension compressing the rim and how the loads are spread through the spokes/rim. The only way spokes would effect the wheel build in that way is if they were stretching and contracting during riding. All that matters is that when wheel build is completed the spokes no longer elongate and cause loss of tension on other spokes.

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I can't read German. If they use carbon in their spokes, carbon is stiffer than steel; kevlar not.
Saying that carbon is stiffer than steel is not true. It CAN be stiffer than steel.

But, we’re also talking about bodies under tension. Not chain stays or down tubes.


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You realize spoke material means absolutely nothing in that regard right? Its all about the tension compressing the rim and how the loads are spread through the spokes/rim. The only way spokes would effect the wheel build in that way is if they were stretching and contracting during riding. All that matters is that when wheel build is completed the spokes no longer elongate and cause loss of tension on other spokes.

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Dude, you realize that you can only tension spokes so much. The rim has to be able to take the tension else it will crack.


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Dude, you realize that you can only tension spokes so much. The rim has to be able to take the tension else it will crack.


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And spoke tension, after a certain point (well below rim or spoke failure) has no impact on wheel stiffness.


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RAKC Industries
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^ exactly. After a certain point it doesnt effect stiffness to any noticeable level. Once that point is reached all you are doing is pulling harder on the rim, the "stretch" of a spoke stops at a certain point.

Even rider/bike weight can matter. A 150lb rider can run a lower tension to get the same feel and strength of a said wheel than a 250lb guy can.

Bicycle wheels are like a cable suspension bridge. When you put weight on the axle, the load is actually carried by pulling on the spokes at the top. The spokes at the bottom actually loose a little bit of tension. Basically spokes are nothing but a bunch of support cables.

Also why when you install and inflate a tire to fully pressure if you check spoke tension it is actually lower.

So material used doesnt matter as long as its strong enough for the task and its fatigue life is long enough be useful in the application.

Technically you could build a wheel with large deep sea kevlar fishing line and it would be as stiff and strong initially as anything else. But its useful life is really short and almost no abrasion resistance. Same with using just basic steel cable. But same problems. Fatigue life as well as just service life in general.

Thats why stainless is the go to. Cheap, lasts a long time, corrosion resistant, any elongation during use comes returns to normal (elasticity) for its working life and is rather resistant to impacts and abrasions.


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^ exactly. After a certain point it doesnt effect stiffness to any noticeable level. Once that point is reached all you are doing is pulling harder on the rim, the "stretch" of a spoke stops at a certain point.

Even rider/bike weight can matter. A 150lb rider can run a lower tension to get the same feel and strength of a said wheel than a 250lb guy can.

Bicycle wheels are like a cable suspension bridge. When you put weight on the axle, the load is actually carried by pulling on the spokes at the top. The spokes at the bottom actually loose a little bit of tension. Basically spokes are nothing but a bunch of support cables.

Also why when you install and inflate a tire to fully pressure if you check spoke tension it is actually lower.

So material used doesnt matter as long as its strong enough for the task and its fatigue life is long enough be useful in the application.

Technically you could build a wheel with large deep sea kevlar fishing line and it would be as stiff and strong initially as anything else. But its useful life is really short and almost no abrasion resistance. Same with using just basic steel cable. But same problems. Fatigue life as well as just service life in general.

Thats why stainless is the go to. Cheap, lasts a long time, corrosion resistant, any elongation during use comes returns to normal (elasticity) for its working life and is rather resistant to impacts and abrasions.


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Yeah. If the Berd spokes are made of typical UHMW polyethylene, they should be ~15x more abrasion resistant than carbon steel. That’s huge.

The problem with it is that it’s really hard to tie into knots. Which is probably some of why the cost is so high.


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RAKC Industries
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From what I can see in the pics (mike needs to chime in on this though)

Its not knotted though unless it is on the threaded end. Its ran into a loop with what appears to be a little nub that goes in the loop to hold it into the spoke holes on the hubs.

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Its not knotted though unless it is on the threaded end. Its ran into a loop with what appears to be a little nub that goes in the loop to hold it into the spoke holes on the hubs.

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Sorry, what I meant to say is that, in order to make the loop on the hub end, they couldn't use a knot like a bowline or something; they had to weave it back into itself to make the loop. Which obviously makes manufacturing more difficult on their end.

If it was simply cutting lengths of cord and tying knots in the end, it would be a lot, lot cheaper.
 

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RAKC Industries
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Ya that makes sense. I dont know anything about how they do that with any form of thread or cable. But would make one question the strength at that one location, the loop. Basic knowledge would be the loop is made simply, thus only half as thick at that location than the rest. But we cant see whats under the outer layer. If it is indeed layered as it appears.

But what little reading Ive done on the material since mike started these threads it seems, though costly, they can do things standard steel cable or rope doesnt respond as well to in a design and manufacturing sense.

Rather intriguing just trying to get a clue what these guys did. But mike's been hammering on them and they are holding up. Even if the marketing is only half of the improvements they say, still could be the future of spoke design. Especially if they deal with crap getting in them like sticks and such better than steel spokes do.

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I'm still curious how the threaded "spoke" attaches to the string part of the spoke. Also, what's the threaded part made of? I suggested to Berd that these be made black instead of white so they'll stay looking new longer. White Spinergy PBO spokes get stained black easily.
 
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