14/15/14 vs. straight-gauge 15

Quoted post said:

Originally posted by Michael
I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that these
might not be strong enough for me - 210 lb rider on a road bike with disc brakes. Opinions?

Bad mistake by Colorado Cyclist. I'm sure if you call them, they'll tell you some BS about how double-butted spokes 15/14/15 stretch and get out of true more than 15 gauge single butted. But you have a right to return them.

Michael said:

I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that these
might not be strong enough for me - 210 lb rider on a road bike with disc brakes. Opinions?

210 pounds, disk brakes? I sure hope you have a _lot_ of those 15 gauge spokes. I would complain,
and get them re-built.

--

David L. Johnson

__o | A mathematician is a machine for turning coffee into theorems. _`\(,_ | -- Paul Erdos
(_)/ (_) |

Rick Onanian said:

Quoted message said:

J999w said:

Despite all the neglect I gave it, it saved my life last night, I crashed and pulverized it.

And you know it saved your life because the control experiment with an unhelmeted head showed...
... no, wait, this is idle supposition on your part, isn't it?

"Saved my life" is always idle supposition, by your standards.

Not necessarily. For instance, if a soldier claimed that a military issue helmet saved his life
from a bullet wound, there probably would be data about the effects of similar bullets on
unhelmeted heads.

Quoted message said:

Have you ever, in fact, hit your head hard enough to crush a helmet, while not wearing a helmet? It
takes a lot of force to crush a helmet; certainly enough to splatter your head.

I suggest you post anonymously when describing your extensive experience of splattering heads; that
is illegal in most jurisdictions.

Quoted message said:

I certainly wouldn't want to live after destroying my skull and brain. I'll take the risk of
uselessly supporting the helmet companies, I certainly waste enough money on other useless stuff.

This is equally well an argument for carrying a lucky rabbit's foot, image of the Virgin Mary,
Discordian Society membership card, etc. - except that only in the case of helmets is there such
telling statistical evidence that they are ineffective. So why not carry all that other junk?

[It is also an argument for wearing a helmet while carrying out activities more prone to head
injuries - like any time you are in your kitchen. I suspect you don't do that, either...]
--
David Damerell <[email hidden]> Kill the tomato!

In article <[email hidden]>, Michael

Quoted message said:

I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that these
might not be strong enough for me - 210 lb rider on a road bike with disc brakes. Opinions?

You mean 14/15/14? I think that would be a better spoke for you than 15, yes.

--Paul

In article <[email hidden]>, [email hidden] says...

Quoted message said:

I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that these
might not be strong enough for me - 210 lb rider on a road bike with disc brakes. Opinions?

Send them back. Why pay for something you didn't order. Especially when it is something inferior.
-----------------
Alex __O _-\<,_ (_)/ (_)

"Dave Thompson" <[email hidden]> wrote

Quoted message said:

Quoted message said:

I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that
these might not be strong enough for me - 210 lb rider on a road bike with disc brakes.
Opinions?

Are you sure they are not double butted spokes? The butting is not easily seen and the taper is
somewhat gradual, not abrupt. The butts are about 1~1
1/2" from either end.

You're right. I have another wheelset with 14/15/14 spokes where the taper is very abrupt and easily
visible. The DT spokes' taper is extremely gradual; I can feel it with my fingers, but I can't see
it at all. Thanks.

Michael-<< I recently had wheels built by Colorado Cyclist. I specified black DT
15/14/15 spokes, but the wheels came with straight-gauge 15-gauge spokes. I'm concerned that these
might not be strong enough for me - 210 lb rider on a road bike with disc brakes. Opinions?

Quoted message said:

Quoted message said:

<BR><BR>

Other than the fact they are not what you ordered...15g straights on a big rider with disc
brakes...not a good setup, IMHO-

Should be 36 hole(at least the rear) and 14/15, built well, of course.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(16)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

[email hidden] (Qui si parla Campagnolo) wrote

Quoted message said:

Should be 36 hole(at least the rear) and 14/15, built well, of course.

Why 36 holes? I guess what I'm asking is, at what point - rider weight, riding style, disc brakes,
etc. - do 36 holes become necessary?

I've been riding 32-hole wheels (though not with disc brakes) for years; the only problem I've had,
two times, is a spoke pulling through a rear drive-side spoke hole on hard-anodized rims, as
predicted by Jobst.

Michael said:

[email hidden] (Qui si parla Campagnolo) wrote

Quoted message said:

Should be 36 hole(at least the rear) and 14/15, built well, of course.

Why 36 holes?

It's the most robust equipment that is available without a significant price penalty. Why _not_ 36
holes, eh?
--
David Damerell <[email hidden]> Distortion Field!

Michael said:

David Damerell <[email hidden]>:

Quoted message said:

Michael said:

[email hidden] (Qui si parla Campagnolo) wrote
>Should be 36 hole(at least the rear) and 14/15, built well, of course.
Why 36 holes?

It's the most robust equipment that is available without a significant price penalty. Why _not_ 36
holes, eh?

Why not 24 holes? Why not 48 holes? etc.

Not 24 because it is less robust. Not 48 because it is more expensive and requires larger hub
flanges, which is starting to take the weight penalty into the realms of the meaningful as well as
making it less likely that spares will be readily available.

Quoted message said:

I look for components that perform well while being as light as possible while being sufficiently
durable for my application.

Wheel failures certainly still happen, so I think we can say that an increase in wheel durability
that does not carry a significant penalty is always good. That's true when going from any number <36
to 36, where the weight penalty is practically nothing, but it's not true when going above 36
because the equipment is significantly more expensive.

Quoted message said:

I was asking if anyone has valid analytical or anecdotal reasons for one over the other.

As you can see, I do.
--
David Damerell <[email hidden]> Distortion Field!

Michael Press said:

Quoted message said:

Quoted message said:

Why 36 holes?

Quoted message said:

Quoted message said:

It's the most robust equipment that is available without a significant price penalty. Why _not_
36 holes, eh?

Quoted message said:

Why not 24 holes? Why not 48 holes? etc.

I'm glad you asked. There is a best ratio between rim cross section, spoke diameter and number of
spokes. As the spoke count is reduced, spoke tension must be increased to prevent slackening in use.
This demands a greater rim strength in bending to bridge between spokes and it requires a stronger
rim bed to prevent spoke pull-outs. At the other end, hubs must be made stronger to retain higher
spoke tension.

Since spoke tension is limited by the circumferential compressive strength of the rim, more spokes
don't hurt although they cannot be as tight as fewer spokes, but they can support a greater load
because it is distributed among more spokes. That is why 48 spokes have served tandems well for
those willing to ignore the fad of fewer spokes. It boils down to how many spokes per length of rim
and for 700c rims it comes down to 36.

All this was developed from over 100 years of trial and error, back in the days when the bicycle was
an important transportation vehicle and racers were not rich professional athletes who could afford
replacing wheels that failed readily. Of course this doesn't affect riders who ride mainly new
wheels and several sets of them.

Quoted message said:

I look for components that perform well while being as light as possible while being sufficiently
durable for my application. It's also nice if they are standard sizes for easy replacement and/or
swapping between my bikes. If that means a wheel with 24 or 32 or 36 or 48 spokes, I don't care,
but I was asking if anyone has valid analytical or anecdotal reasons for one over the other.

I'm glad to see you qualify that with "for my application". That puts a different spin on it.

Jobst Brandt [email hidden] Palo Alto CA

Jobst Brandt said:

Michael Press said:

Quoted message said:

> Why 36 holes?

Quoted message said:

Quoted message said:

It's the most robust equipment that is available without a significant price penalty. Why _not_
36 holes, eh?

Quoted message said:

Why not 24 holes? Why not 48 holes? etc.

I'm glad you asked. There is a best ratio between rim cross section, spoke diameter and number of
spokes. As the spoke count is reduced, spoke tension must be increased to prevent slackening in
use. This demands a greater rim strength in bending to bridge between spokes and it requires a
stronger rim bed to prevent spoke pull-outs. At the other end, hubs must be made stronger to
retain higher spoke tension.

Since spoke tension is limited by the circumferential compressive strength of the rim, more spokes
don't hurt although they cannot be as tight as fewer spokes, but they can support a greater load
because it is distributed among more spokes. That is why 48 spokes have served tandems well for
those willing to ignore the fad of fewer spokes. It boils down to how many spokes per length of
rim and for 700c rims it comes down to 36.

All this was developed from over 100 years of trial and error, back in the days when the bicycle
was an important transportation vehicle and racers were not rich professional athletes who could
afford replacing wheels that failed readily. Of course this doesn't affect riders who ride mainly
new wheels and several sets of them.

[...]

You write that for regular bikes 36 holes are optimal, and "48 spokes have served tandems well". I'm
curious how the optimum spoke count scales with load. I think it's reasonable to assume that the
tandem's wheels will carry twice the load of the 36 spoke wheels. Yet they only have 1/3 more
spokes. I would expect a 48 spoke wheel to serve two riders about as "well" as a 24 spoke wheel
serves one.

Imagine a 24 spoke wheel that is sitting on the floor and is carrying 100 lbs. It is bent out of
round a bit to accomodate the load. If we now double the spoke count while simultaneously doubling
the load, nothing should move. That's assuming the rim really acts like a wet noodle, the way you
describe it in your book "The Bicycle Wheel". Even if rim rigidity played a role, the tandem rim
might be twice as strong as the regular one, so I would expect the tandem wheel carrying 200 lbs to
look very similar to the 24 spoke wheel carrying 100 lbs. Hence the cyclical stresses will be
similar in 48 spoke tandem wheels and 24 spoke regular wheels, and their durability should be the
same, too.

I've never ridden a tandem. Are 48 spoke wheels considered durable? Does anyone feel the need for
more spokes?

-Till Rosenband

Till Rosenband said:

Quoted message said:

Quoted message said:

> It's the most robust equipment that is available without a significant price penalty. Why _not_
> 36 holes, eh?

Quoted message said:

Quoted message said:

Quoted message said:

Why not 24 holes? Why not 48 holes? etc.

Quoted message said:

Quoted message said:

I'm glad you asked. There is a best ratio between rim cross section, spoke diameter and number of
spokes. As the spoke count is reduced, spoke tension must be increased to prevent slackening in
use. This demands a greater rim strength in bending to bridge between spokes and it requires a
stronger rim bed to prevent spoke pull-outs. At the other end, hubs must be made stronger to
retain higher spoke tension.

Quoted message said:

Quoted message said:

Since spoke tension is limited by the circumferential compressive strength of the rim, more
spokes don't hurt although they cannot be as tight as fewer spokes, but they can support a
greater load because it is distributed among more spokes. That is why 48 spokes have served
tandems well for those willing to ignore the fad of fewer spokes. It boils down to how many
spokes per length of rim and for 700c rims it comes down to 36.

Quoted message said:

Quoted message said:

All this was developed from over 100 years of trial and error, back in the days when the bicycle
was an important transportation vehicle and racers were not rich professional athletes who could
afford replacing wheels that failed readily. Of course this doesn't affect riders who ride mainly
new wheels and several sets of them.

Quoted message said:

You write that for regular bikes 36 holes are optimal, and "48 spokes have served tandems well".
I'm curious how the optimum spoke count scales with load. I think it's reasonable to assume that
the tandem's wheels will carry twice the load of the 36 spoke wheels. Yet they only have 1/3 more
spokes. I would expect a 48 spoke wheel to serve two riders about as "well" as a 24 spoke wheel
serves one.

It is a matter of how many spoke fall in the load affected zone ad that is not linear with load. I'm
not saying that 48 spoke tandem wheels are optimal, only that there is benefit in that number of
spokes using otherwise conventional dim profiles. I'm sure a better cross section could be achieved
for tandems.

Quoted message said:

Imagine a 24 spoke wheel that is sitting on the floor and is carrying 100 lbs. It is bent out of
round a bit to accommodate the load. If we now double the spoke count while simultaneously
doubling the load, nothing should move. That's assuming the rim really acts like a wet noodle, the
way you describe it in your book "The Bicycle Wheel". Even if rim rigidity played a role, the
tandem rim might be twice as strong as the regular one, so I would expect the tandem wheel
carrying 200 lbs to look very similar to the 24 spoke wheel carrying 100 lbs. Hence the cyclical
stresses will be similar in 48 spoke tandem wheels and 24 spoke regular wheels, and their
durability should be the same, too.

Quoted message said:

I've never ridden a tandem. Are 48 spoke wheels considered durable? Does anyone feel the need for
more spokes?

I started the 48 spoke concept with Spence Wolf of Cupertino Bike Shop when tandems in the 1950's
suffered spoke and rim failures at a great rate. In those days one cold request rims with different
drillings. In any case, the wheels made a big difference and have been used by average sized tandem
riders who travel.

Jobst Brandt [email hidden] Palo Alto CA

[email hidden] (Qui si parla Campagnolo) wrote in message
news:<[email hidden]>...

Quoted message said:

Michael-<< Why 36 holes? I guess what I'm asking is, at what point - rider weight, riding style,
disc brakes, etc. - do 36 holes become necessary? >><BR><BR>

Most adult male riders shouold use at least a 36h rear. Geezzz, 4 spokes weigh 28 grams, but a
36 is stronger than 32, all else being the same. I will never understand this reluctance toward
36h, but methinks it has soimething to do with marketing and once again, trying to save $ by
offering only 32 hole. A local MO outfit doesn't even carry 36h hubs/rims anymore...altho they
are easy to get.

What disadvantage can you think of for 36 vs 32 hole??

For you(200 pounds?) and disc brakes???

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"

This one will get quickly shot down but as at least two people here are eminently more qualified to
address the science, but I've always contended that the 32h wheel was stronger because the spoke
count was Base 2. Just for consideration, note how the 32h wheel has 8 pairs of spokes on each side
rather than 9 pairs. My theory is that this allows more equal opposing longitudinal forces while
sharing the opposition to latitudinal forces that the 9 pairs do on the 36h wheel. Wait,...let me
put my helmet on.

"Gary Kamieneski" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

This one will get quickly shot down but as at least two people here are eminently more qualified
to address the science, but I've always contended that the 32h wheel was stronger because the
spoke count was Base 2. Just for consideration, note how the 32h wheel has 8 pairs of spokes on
each side rather than 9 pairs. My theory is that this allows more equal opposing longitudinal
forces while sharing the opposition to latitudinal forces that the 9 pairs do on the 36h wheel.
Wait,...let me put my helmet on.

That's not so at all. The fact is, 32 spoke wheels have only become feasible since rims were welded
at the seam. With unwelded rims, if you lace 32 spokes and leave a gap at the valve hole for your
pump, then you leave a corresponding gap at the seam, which of course pulls the seam apart straight
away. With 36 spokes (or 28 for that matter) the spokes either side of the seam pull it together. Of
course now, with welded rims, you're relying on that weld not letting go.

That's the _real_ reason the experts advocate 36 spoke rims.

Regards,

Suzy (tongue firmly planted in cheek)

Suzy Jackson said:

Quoted message said:

This one will get quickly shot down but as at least two people here are eminently more qualified
to address the science, but I've always contended that the 32h wheel was stronger because the
spoke count was Base 2. Just for consideration, note how the 32h wheel has 8 pairs of spokes on
each side rather than 9 pairs. My theory is that this allows more equal opposing longitudinal
forces while sharing the opposition to latitudinal forces that the 9 pairs do on the 36h wheel.
Wait,...let me put my helmet on.

Quoted message said:

That's not so at all. The fact is, 32 spoke wheels have only become feasible since rims were
welded at the seam. With unwelded rims, if you lace 32 spokes and leave a gap at the valve hole
for your pump, then you leave a corresponding gap at the seam, which of course pulls the seam
apart straight away. With 36 spokes (or 28 for that matter) the spokes either side of the seam
pull it together. Of course now, with welded rims, you're relying on that weld not letting go.

Quoted message said:

That's the _real_ reason the experts advocate 36 spoke rims.

I take it you say that in jest, yet it is amazing how popular that belief was for all the years
before a stress analysis was published. The number of bicycle shop owners and mechanics that do not
read and are unaware that some of their their customers are better informed about wheels than they
are, amazes me. I recently overheard your comment about spoke patterns in a bicycle shop.

On that subject, Fiamme rims used a rivet on either side of the butt joint and then for a long time
had none before reverting to rivets in their waning days. No MA-2 rims (of which I have a reasonable
cache) have anything holding them together at the joint except friction from the alignment insert.
These shenanigans, among others, moved me to write "the Bicycle Wheel."

avocet.comwheelbook.htmlOpen ↗

Jobst Brandt [email hidden] Palo Alto CA

Quoted message said:

their waning days. No MA-2 rims (of which I have a reasonable cache) have anything holding them
together at the joint except friction from the alignment insert.

jobst, i think they are jointed by diffusion welding. it's a common solid-phase method of
joining aluminum.

jb

jim beam said:

Quoted message said:

their waning days. No MA-2 rims (of which I have a reasonable cache) have anything holding them
together at the joint except friction from the alignment insert.

Quoted message said:

Jobst, I think they are jointed by diffusion welding. It's a common solid-phase method of joining
aluminum.

The joint can be pulled apart by hand to expose a well fitting sleeve. Pleas explain how my rims
could be diffusion welded, these or the Fiamme rims remaining from the days of tubulars.

Jobst Brandt [email hidden] Palo Alto CA

relax

i said "i think" because some rims were and my ma2 looks similar to those examples. i do not however
plan on pulling my ma2 apart just to argue with you.

have a beer. go to bed.

diffusion welding is really cool though.

Quoted message said:

jim beam said:

Quoted message said:

their waning days. No MA-2 rims (of which I have a reasonable cache) have anything holding them
together at the joint except friction from the alignment insert.

Quoted message said:

Jobst, I think they are jointed by diffusion welding. It's a common solid-phase method of joining
aluminum.

The joint can be pulled apart by hand to expose a well fitting sleeve. Pleas explain how my rims
could be diffusion welded, these or the Fiamme rims remaining from the days of tubulars.

Jobst Brandt [email hidden] Palo Alto CA