spoke nipple life expectancy?

[Skuke]

On a recent ride, I broke a spoke nipple just under the head where it rides against the rim eyelet
(rear wheel). No biggie, I just opened the brake and continued with the ride for another 25 miles or
so. I stopped at the LBS on the way home and bought a nipple.

When I took the rim tape off, there was a bit of corrosion around most of the nipples and that
concerned me a bit. Anyhow, I replace the one broken nipple and while truing the wheel, another
nipple broke also just under the head. I had a spare and replaced the second nipple. Then a third
broke! So I go back to the LBS and buy 32 nipples as I plan to now replace them all. While removing
the nipples, a 4th breaks! I noticed that they were only failing on the drive side and the ones
successfully removed had the anodizing worn off where it contacts the eyelet (to be expected). I'm
guessing that micro fractures started in the contact area and propagated from there.

Some info for those of you who will want to know: Wheelsmith alloy 15ga nipples, Wheelsmith
14/15(?)ga double butted spokes, Mavic UB Reflex 32 hole rims. Built about 8 years ago, now has
aproximately 13k miles and has had virtually zero maintainance since (minor trueing 2-3 times).
Campy spoke prep was used in the inital build. Although this time, I only had Phil Wood bottom
bracket grease and used that. I weigh about 130-135 pounds and ride primarily in the SF bay area.
When caught in the rain, I do NOT remove the tires when I get home to "properly" dry out the wheels,
rim tape...

I'm perfectly satisfied that they have lasted 8+ years and am just curious if that is the usual life
expectancy of alloy nipples. I am a little concerned that they might have popped like a broken
zipper on my ride though. Less load, but should I have front wheel concerns? I'm complacent and lazy
enough that I don't want to rebuild the front wheel unless I really have to!

TIA, Skuke

 

[Sheldon Brown]

A shy person wrote:

> On a recent ride, I broke a spoke nipple just under the head where it rides against the rim eyelet
> (rear wheel)...
>
> When I took the rim tape off, there was a bit of corrosion around most of the nipples and that
> concerned me a bit. Anyhow, I replace the one broken nipple and while truing the wheel, another
> nipple broke also just under the head. I had a spare and replaced the second nipple. Then a
> third broke! So I go back to the LBS and buy 32 nipples as I plan to now replace them all.
> While removing the nipples, a 4th breaks! I noticed that they were only failing on the drive
> side and the ones successfully removed had the anodizing worn off where it contacts the eyelet
> (to be expected). I'm guessing that micro fractures started in the contact area and propagated
> from there.
>
> Some info for those of you who will want to know: Wheelsmith alloy 15ga nipples, ...
>
> I'm perfectly satisfied that they have lasted 8+ years and am just curious if that is the usual
> life expectancy of alloy nipples. I am a little concerned that they might have popped like a
> broken zipper on my ride though. Less load, but should I have front wheel concerns? I'm complacent
> and lazy enough that I don't want to rebuild the front wheel unless I really have to!

This is not an unusual occurrence when aluminum ("alloy") nipples are used with spokes that are a
little too short.

If the steel spokes extended farther into the nipple head, they would have added support and most
likely obviated the risk of this sort of failure.

Sheldon "Better A Bit Too Long Than A Bit Too Short" Brown +------------------------------------+
| Immigrants are not our burden, | They are our wealth --Jane Adams |
+------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone 617-244-9772
FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Bob Denton]

On 24 Feb 2003 13:31:19 -0800, [email protected] (skuke) wrote:

>I'm perfectly satisfied that they have lasted 8+ years and am just curious if that is the usual
>life expectancy of alloy nipples. I am a little concerned that they might have popped like a broken
>zipper on my ride though. Less load, but should I have front wheel concerns? I'm complacent and
>lazy enough that I don't want to rebuild the front wheel unless I really have to!
>
>TIA, Skuke

My last wheel with aluminum nipples (DT) lasted about 4 months, and I started splitting nipples on a
particular bridge, almost every time I crossed on the return.

I ride along the beach road here in Florida, and I assume that the puddles I often ride through have
some salt content.

I replaced all the nipples with brass and haven't had a nipple problem since.

cu Bob Denton Gulf Stream International Delray Beach, Florida www.sinkthestink.com Manufacturers of
Sink the Stink

 

[Qui Si Parla Ca]

skuke-<< I broke a spoke nipple just under the head where it rides against the rim eyelet (rear
wheel) << Anyhow, I replace the one broken nipple and while truing the wheel, another nipple broke
also just under the head. << I had a spare and replaced the second nipple. Then a third broke! <<
While removing the nipples, a 4th break

<< Some info for those of you who will want to know: Wheelsmith alloy 15ga nipples,

Bing, bing, bing, we have a winner!!!

use brass nipples, not aluminum alloy.

<< I'm perfectly satisfied that they have lasted 8+ years and am just curious if that is the usual
life expectancy of alloy nipples.

About 13000 miles??

Brass last longer-

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

[Skuke]

Firstly, why do you think I'm "shy"? Because I use an anonymous, free email address and alias?
That's not shyness, it's a concern for trying to maintain my privacy and that of my family. Also,
it's to try and reduce the amount of Spam I receive. Now I realize that my true identity can
probably be found by those who want to put forth the time and energy, but my way just keeps the
"honest people honest". That you choose to use your real name and a "good" email address is your
perogative. Having said that, Mr. Brown, do know that I have perused your website and found it to be
of much help on many occasions and I do respect your opinions. Thank you for the input regarding my
spoke nipples.

The spokes are either flush with nipple head (into the screwdriver slot) or extend no more than
about 1mm past (in towards the hub). I don't believe any of the spokes are even short by one thread
pitch in the nipple. I believe the spoke length is correct, yes?

Thanks, skuke

> A shy person wrote:

> <snip a bunch of stuff>

>
> This is not an unusual occurrence when aluminum ("alloy") nipples are used with spokes that are a
> little too short.
>
> If the steel spokes extended farther into the nipple head, they would have added support and most
> likely obviated the risk of this sort of failure.

 

[Skuke]

Yes, but my question is: "Is 8 years and 13k miles with a 130+lb rider about normal for
Aluminum nipples?"

Why did I use Aluminum over brass? Because of weight, color availability, and that's all I've ever
used. I have never had any part of a wheel fail in 18 years of riding (road or dirt). Of course,
this wheel set is the longest time and milage I ever owned so I would just like to have an idea of
life expectancy.

Thanks, skuke

>
> Brass last longer-
>
>
> Peter Chisholm Vecchio's Bicicletteria

 

[Sheldon Brown]

A timid person wrote:

> Firstly, why do you think I'm "shy"? Because I use an anonymous, free email address and alias?
> That's not shyness, it's a concern for trying to maintain my privacy and that of my family. Also,
> it's to try and reduce the amount of Spam I receive. Now I realize that my true identity can
> probably be found by those who want to put forth the time and energy, but my way just keeps the
> "honest people honest".

I don't like to quote without some sort of attribution, but since you didn't choose to sign your
posting, I had no better way to attribute it.

I commmonly use the attribute "shy" in preference to, say, "anonymous" "stealthy" or "paranoid"
because I prefer the gentler term.

> That you choose to use your real name and a "good" email address is your perogative. Having said
> that, Mr. Brown, do know that I have perused your website and found it to be of much help on many
> occasions and I do respect your opinions. Thank you for the input regarding my spoke nipples.
>
> The spokes are either flush with nipple head (into the screwdriver slot) or extend no more than
> about 1mm past (in towards the hub). I don't believe any of the spokes are even short by one
> thread pitch in the nipple. I believe the spoke length is correct, yes?

That does sound correct. Another possibility is that the nipple seat had not been properly
lubricated when the wheel was built. In this case, the friction of the nipples being tightened
against the spoke holes oculd have scored the undersides of the nipple heads, creating a
stress riser.

I don't recall what rim you have, but if it had plain drilled spoke holes, without eyelets/ferrules,
the sharp edge of the spoke hole could be a contributing factor. It is not good practice to use
aluminimimium nipples with this sort of rims. (Note British spelling!)

It is not "normal" for nipples to break at any age or mileage.

Sheldon "Nothing To Hide, Can Live With The Spam" Brown
+-------------------------------------------------------+
| It is better to be victimized occasionally, | than to go through life filled with suspicion. |
| --Elbert Hubbard |
+-------------------------------------------------------+ Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Jay Beattie]

"Sheldon Brown" <[email protected]> wrote in message
news:[email protected]...
> A timid person wrote:
>
> > Firstly, why do you think I'm "shy"? Because I use an anonymous,
free
> > email address and alias? That's not shyness, it's a concern for trying to maintain my privacy
> > and that of my family. Also, it's to try and reduce the amount of Spam I receive. Now I realize
> > that my true identity can probably be found by those who want to put forth
the
> > time and energy, but my way just keeps the "honest people honest".
>
> I don't like to quote without some sort of attribution, but since you didn't choose to sign your
> posting, I had no better way to attribute
it.
>
> I commmonly use the attribute "shy" in preference to, say, "anonymous" "stealthy" or "paranoid"
> because I prefer the gentler term.
>
> > That you choose to use your real name and a "good" email address is your perogative. Having
> > said that, Mr. Brown, do know that I have perused your website and found it to be of much help
> > on many
occasions
> > and I do respect your opinions. Thank you for the input regarding
my
> > spoke nipples.
> >
> > The spokes are either flush with nipple head (into the screwdriver slot) or extend no more than
> > about 1mm past (in towards the hub). I don't believe any of the spokes are even short by one
> > thread pitch
in
> > the nipple. I believe the spoke length is correct, yes?
>
> That does sound correct. Another possibility is that the nipple seat had not been properly
> lubricated when the wheel was built. In this case, the friction of the nipples being tightened
> against the spoke holes oculd have scored the undersides of the nipple heads, creating a
> stress riser.
>
> I don't recall what rim you have, but if it had plain drilled spoke holes, without
> eyelets/ferrules, the sharp edge of the spoke hole
could
> be a contributing factor. It is not good practice to use
aluminimimium
> nipples with this sort of rims. (Note British spelling!)
>
> It is not "normal" for nipples to break at any age or mileage.

Sheldon, have you had any problems with the MA3? I oiled the hell out of the nipples and spoke holes
but kept lathing-off the nipple head (DT brass/32 hole). I would get the wheel up to tension, and
then PING! -- there goes a nipple. I have never had this problem on any other rim, and did not have
the same problem on the 36 hole version. -- Jay Beattie.

 

[Sheldon Brown]

Jay Beattie asked:

> Sheldon, have you had any problems with the MA3? I oiled the hell out of the nipples and spoke
> holes but kept lathing-off the nipple head (DT brass/32 hole). I would get the wheel up to
> tension, and then PING! -- there goes a nipple. I have never had this problem on any other rim,
> and did not have the same problem on the 36 hole version. --

I haven't built a lot of wheels with MA3s (these days I spend a lot more time at a keyboard than a
truing stand) but we've sold a ton of them with very few problems. I have no beef with them.

For my own use, I prefer the Open Pro, but it is twice the price. For heavier applications, or wider
tires, I often recommend the Sun CR-18.

Sheldon "Em Ah Trois" Brown +--------------------------------------------+
| If it can't be expressed in figures, | it is not science; it is opinion. | --Robert A.
| Heinlein |
+--------------------------------------------+ Harris Cyclery, West Newton, Massachusetts Phone
617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

 

[Skuke]

Mr Brown,

>
> I don't like to quote without some sort of attribution, but since you didn't choose to sign your
> posting, I had no better way to attribute it.

I signed my original post "TIA, skuke". But, I answer to most anything including Shy, and Timid. I
was just curious as to why you addressed me as "Shy" is all.

> Another possibility is that the nipple seat had not been properly lubricated when the wheel
> was built.

The nipple seat was lubed with Campy spoke prep on the original build. On the few subsequent
trueings, I put some lube (probably TriFlow cuz it's handy) on the spoke so it would run down the
threads and on the nipple so it would run into the eyelet hole.

In this
> case, the friction of the nipples being tightened against the spoke holes oculd have scored the
> undersides of the nipple heads, creating a stress riser.

The tensioning, (whether original or subsequent trueing is unknown) did remove the anodizing. I
looked at a few of the replaces nipples under a 10x loop and there is scoring on most of them. They
are small, but that is how stress risers start and propagate.

>
> I don't recall what rim you have,

Mavic Reflex UB 32 hole circa 1995. There are factory eyelets in the holes.

> It is not good practice to use aluminimimium nipples with this sort of rims. (Note British
> spelling!)

I think you have two too many "im" there.

>
> It is not "normal" for nipples to break at any age or mileage.

Thanks, Skuke aka Shy and Timid