Double butted or straight gauge spokes???????

JRB · Jun 21, 2004

Me thinks having been riding 14/15s for some time and getting some 14g, the straight are stiffer. That doesn't answer your question, but I would think that the shoulder would cause the failure if you are referring to flange failure. Maybe the DTs are bigger at the shoulder. A 14/15g and a 14g should be the same at the hub. I could only say that it would be mfg differences.

*sorry - I confused myself trying to think this through.

dw · Jun 21, 2004

Cant think of one reason (other than cost) to go straight gage personally. Most of the 823's Ive seen broken have cracked at the eyelet, so I dont think a straight gage will help there. For next year the 823 is improved in this area as far as I understand. Rims are just one of those items that most people will kill no matter what unfortunately.

Acadian · Jun 21, 2004

Get Hopes..

psycle-on · Jun 21, 2004

Not being an engineer, my guess is that straight gauge would not make any difference for flat spots since your weight is actually hanging from the spokes at the top of the wheel, not pushing down on the bottom of the wheel where it is in contact with the ground and absorbing impacts creating flatspots.

thaflyinfatman · Jun 21, 2004

psycle-on said:
Not being an engineer, my guess is that straight gauge would not make any difference for flat spots since your weight is actually hanging from the spokes at the top of the wheel, not pushing down on the bottom of the wheel where it is in contact with the ground and absorbing impacts creating flatspots.

I think ideally spoke tension should be enough that each spoke is ALWAYS under (positive) tension, even when it's at the bottom of the wheel, being "pushed" against. Obviously the internal forces will change according to where the spokes are (with reference to angular position at the time of the impact), but the spokes at the bottom should still always be under tension.

Edit: that was kind of irrelevant, wasn't it...

psycle-on · Jun 21, 2004

Brian HCM#1 said:
If they made spokes I would

Maybe some Hope rims?

Or should it be "I hope these Mavic's don't flat spot"
:devil:

Westy · Jun 21, 2004

Lose weight

.

psycle-on · Jun 21, 2004

thaflyinfatman said:
I think ideally spoke tension should be enough that each spoke is ALWAYS under (positive) tension, even when it's at the bottom of the wheel, being "pushed" against. Obviously the internal forces will change according to where the spokes are (with reference to angular position at the time of the impact), but the spokes at the bottom should still always be under tension.

Edit: that was kind of irrelevant, wasn't it...

LOL... I guess what I was trying to say is the way spokes are, the nipple flanges do nothing to resist a pushing in of a rim - ie, it is the strength of the circle of the rim, not the spokes?

thaflyinfatman · Jun 21, 2004

psycle-on said:
LOL... I guess what I was trying to say is the way spokes are, the nipple flanges do nothing to resist a pushing in of a rim - ie, it is the strength of the circle of the rim, not the spokes?

Well (this is entirely coincidental, i didn't think of this when I posted that first comment) having greater spoke tension would apply a more even pressure on the rim, so that the compressive force the spokes apply to the rim on either side of the point of impact, prevents the rim being pushed in (flatspotting) because the sections of the rim immediately beside the point of impact, can't push outwards to allow the rim to bend in at one point.

If that made no sense, never mind, I'm retarded.

psycle-on · Jun 21, 2004

thaflyinfatman said:
Well (this is entirely coincidental, i didn't think of this when I posted that first comment) having greater spoke tension would apply a more even pressure on the rim, so that the compressive force the spokes apply to the rim on either side of the point of impact, prevents the rim being pushed in (flatspotting) because the sections of the rim immediately beside the point of impact, can't push outwards to allow the rim to bend in at one point.

If that made no sense, never mind, I'm retarded.

Makes sense to me

But do you think spoke gauge makes any difference?

thaflyinfatman · Jun 21, 2004

psycle-on said:
Makes sense to me
But do you think spoke gauge makes any difference?

Stop asking for relevance!

haha I have no idea... I guess it would be stiffer or something if you used straight gauge, but I really don't know. My knowledge of wheels and what makes them tick is very limited, I don't even know what the deal with butting is (is it an average of 14g if it's double butted, or is it 14g at the thickest point, or what?), blah blah, can't build my own wheels, too tired to be able to make sense of my own ramblings, blah....gahohgoaaa

Repack · Jun 21, 2004

dw said:
Cant think of one reason (other than cost) to go straight gage personally. Most of the 823's Ive seen broken have cracked at the eyelet, so I dont think a straight gage will help there. For next year the 823 is improved in this area as far as I understand. Rims are just one of those items that most people will kill no matter what unfortunately.

I have always been told that DB spokes have a higher tensile strength because they are drawn (not rolled like 14g), but that 14g is stiffer b/c they are thicker.
Based on this info, I drew the conclusion that 14g is better for dh wheels only because the stiffer wheel will keep the stress more evenly dustributed across the rim, making it stronger.
But what I just wrote has nothing to do with 823's. Just buy 729's and stay happy.

Any truth to this dw?

HTFR · Jun 21, 2004

the way i see it is if you are ripping spokes out of the rim or the nipple or snaping at the ends and butted spoke should not make a difference. but if you have noticed when a wheel is tacoed or really bent, the bend is in the middle of the spoke. so as long as your not landing tweeked or off camber or doing harsh sidways hit etc, i butted spoke should be fine.
so
up/down hits it probibly will not matter
side/side hits you would probibly notice it

but, then again, i have no proof i have never ridden 14/15/13 spokes only 14s, and i don't normally brake rims, its just what i noticed. can anyone back me up on this? or am i way off? :help:

binary visions · Jun 21, 2004

It's always been my understanding that DB spokes tend to snap less because they flex slightly (instead of snapping). That means you can have a much higher tension wheel without having broken spokes, which in turn means it is stronger. Building straight-gauge spokes to the same tension as DB spokes tends to cause the spokes to snap.

Not having gone through a lot of wheels, I don't have proof of any of this, but it makes perfect sense to me...

theflyinfatman: I've never seen a butted spoke that didn't list multiple gauge numbers. That is, I've never seen a spoke referred to as "butted 14g", you usually see "butted 14/15g" which means the ends are 14g and the middle is 15g...

Repack · Jun 21, 2004

I forgot to say that 14/15 spokes are easier to tension/true. I get a much better feel from them. Again, I believe that it is because of the stiffness, but perhaps more so from the fact that the thinner spokes are bent/deflected less when they cross the other spokes.

Jeremy R · Jun 21, 2004

Brian HCM#1 said:
Well I'm going back to Wheelsmith 14g spokes, just ordered some this morning. I'll see if this make any difference.......Probably not.

That is the same setup that I had on mine.
I flatspotted my rear, put in a tube, and then my der. went into
my spokes and stripped out a couple of holes ruining the rim.
Then again, my front 823 is still perfectly true, and I have been riding the pizz out of it since December. It has been through the US OPen and 2 Nationals among a bunch of other stuff.
So who knows. Try it and see. :cool:

bomberz1qr20 · Jun 21, 2004

Everyone who has read or replied to this thread needs to read "The Bicycle Wheel" by Jobst Brandt. It covers all of these questions, from an engineering POV.

DB spokes are better, period. They are drawn (swaged) through a die, this work hardens them. They are therefore stronger AND lighter.

This is the same thing that makes a cold-forged crank or stem so desirable.

DB spokes are harder to true, because a thinner mid section will "wind-up" more than a thicker one. This can be dealt with by a good wheel builder.

Where do almost ALL spokes fail? At the elbow. Not the mid section, unless you crash. (and most any spokes will be toast in a good sidways crash.) Elbows on a 14g spoke and a 14/15g spoke are the same.

A spoke fails at the elbow from insufficient tension. This is cummulative, and will happen over time, at any time. Ever broke a spoke 'JRA'? This is from a build up of fatigue at the elbow of the spoke. A spoke at low tension will go through a greater range of fatique cycles, and fail early. (think: bending a paper clip back and forth) A spoke at proper tension can resist these fatigue cycles (try to bend that paper clip if it's in very high tension)

Optimum tension is determined by over all rim strength. The more a rim can resist filing at the spoke hole, the greater the over-all tension can be.

Wanna save your wheels? Have them built by a good builder, and KEEP UP ON THE TENSION! Have them re-tensioned and trued after they are broken in, and give them some TLC every once in awhile.

Jm_ · Jun 21, 2004

bomberz1qr20 said:
Where do almost ALL spokes fail? At the elbow. Not the mid section, unless you crash. (and most any spokes will be toast in a good sidways crash.) Elbows on a 14g spoke and a 14/15g spoke are the same.

.

Naw, all the spokes i've broken always snap near or at the nipple.

I just broke one yesterday (it's been a long time since I've broken any though). That's what I get for not checking my tension in a long time of course

I like how DT spokes "taper" much more smoothly than Wheelsmith.

I have had zero problems from my wheel built with revolution spokes strangely.

thaflyinfatman · Jun 21, 2004

binary visions said:
theflyinfatman: I've never seen a butted spoke that didn't list multiple gauge numbers. That is, I've never seen a spoke referred to as "butted 14g", you usually see "butted 14/15g" which means the ends are 14g and the middle is 15g...

Oh righto, I didn't know that. You can tell I'm not a wheelbuilder eh..

kidwoo · Jun 21, 2004

I use straight gauge dt spokes on all my "heavy duty" bike wheels and since switching from DB spokes about 2 years ago on the wheels I build, with one exception, I've had 8 wheels between three bikes and only had one failure. I flatspotted a sun ryno lite on a cased landing that also cracked a bb spindle, cracked a crank and put a subcutaneous baseball in the arch of my foot. I don't think anything would have prevented the death of that rim.

I still ride every other one of those wheels (minus one set of 321s I sold to someone who rides them currently). Ages of those wheels vary from 2 months to two years but I have noticed one thing. I have to true them a whole lot less. I have a few higher volume wheel building friends who hold true to the theory that if you don't allow a wheel to flex, it won't reach degrees of flatspots and getting out of true to the point where the rim wants to stay there. One of these fellas used to build wheels for sun ringle's riders if that gives him any more cred. From what I've seen on my own wheels and a few folks I ride DH with a lot (at northstar mostly where brian and luc accomplished their latest feats) this holds pretty true (forgive the pun).

I literally have not broken a spoke on anything but DB laced wheels either. As far as the accepted theories on db spokes go, they do make sense. But they are in direct opposition to everything I've seen in real life regarding wheels that get the living crap beat out of them......mine for instance. So in the meantime, I try to build my wheels stiff as poo and the best way to do this it seems to me is to use spokes that aren't designed to let your wheels get to points of deformity where you don't want them to potentially stay.

my 2 cents

edit: If someone can explain to me why I'm wrong, please do so. I am by no means a master wheelbuilder. This line of thinking seems to be working for me, I know it's not the popular one.

Repack · Jun 21, 2004

kidwoo said:
Ages of those wheels vary from 2 months to two years but I have noticed one thing. I have to true them a whole lot less. I have a few higher volume wheel building friends who hold true to the theory that if you don't allow a wheel to flex, it won't reach degrees of flatspots and getting out of true to the point where the rim wants to stay there. One of these fellas used to build wheels for sun ringle's riders if that gives him any more cred. From what I've seen on my own wheels and a few folks I ride DH with a lot (at northstar mostly where brian and luc accomplished their latest feats) this holds pretty true (forgive the pun).

I agree with every word of that. I am a very good wheel builder and have built hundreds of them. I have been doing it for so long that I can get a wheel within a couple of millimeters of perfect true/round before it gets near a truing stand. I also feel that a stiffer wheel is stronger, even if the tensile strength of the spokes are different. I know that db's are stronger. I'm not trying to contradict that. Does anybody know the tensile strength of a spoke? I do not, but I am willing to bet that it is somewhere over 1,000# per spoke. Multiply by 32 and you have enough metal to lift a bus. Breaking strength alone is not the only factor. When you ride, you weight is hanging off of the top ~1/3 of the spokes. Every time the wheel rotates, every spoke sees a significant change in the amount of tension on it. It is the cycle that causes a wheel to go out of true. This was a huge opstacle for low spoke count wheel builders and one of the reasons why Bontrager and Shimano wheels have such high tension.
While I do not believe that spoke choice has much of an effect when it comes to catastrophic failure, I do believe it has a very real effect on the overall longevity of the wheel. Spoke tension is another reason why no-dish wheels are better, and why DT Swiss makes hubs with asymetrical flange diameters.

Double butted or straight gauge spokes???????

MMMMMMMMM BEER!!!!!!!!!!

JRB

Guest

Wiffle Ball ninja

MMMMMMMMM BEER!!!!!!!!!!

Born Again Newbie

:)

MMMMMMMMM BEER!!!!!!!!!!

Turbo Monkey

:)

the teste

:)

MMMMMMMMM BEER!!!!!!!!!!

Turbo Monkey

:)

Turbo Monkey

MMMMMMMMM BEER!!!!!!!!!!

Turbo Monkey

Monkey

The voice of reason

Turbo Monkey

<b>x</b>

Turbo Monkey

sled dog's bollocks

Turbo Monkey

Artisanal Tweet Curator

Turbo Monkey