What do these wheels stand on?

"Carl Fogel" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

As I understand things, a normal pre-tensioned bicycle
wheel "stands" [1] on its lower spokes, which lose tension
as they roll under the hub, effectively compressing, while
the other spokes show no significant change in tension.

At the same time, the bottom of the rim flattens out a
tiny bit.

So how do these odd wheels work?

Looks fundamentally the same as a regular spoked rim. It's a
pre-stressed structure that operates in the same manner as
what we're used to. They've changed the method of attaching
the "spokes" to the hub, but it doesn't change the overall
concept significantly. They're attempting to improve the
interfaces and the material in tension. Looks to be trued in
the same manner, although there may be some uniqueness due
to the shared tension member from one side to the other if
the spoke is allowed to move freely through the hub
interface.

Cheers,

Scott..

Carl Fogel said:

As I understand things, a normal pre-tensioned bicycle
wheel "stands" [1] on its lower spokes, which lose tension
as they roll under the hub, effectively compressing, while
the other spokes show no significant change in tension.

Quoted message said:

At the same time, the bottom of the rim flattens out a
tiny bit.

Quoted message said:

So how do these odd wheels work?

Quoted message said:

topolinotech.comtopolinotech.comOpen ↗

Quoted message said:

topolinotech.comWheelSpokes.htmOpen ↗

Neither the pictures nor the text make this clear to me.
However, I notice that the spokes are anchored to each other
at their crossings. The whole concept reeks of "it's
different and therefore good".

Quoted message said:

They seem to bend double-length spokes slightly around the
hub, from one side of the rim to the other.

Quoted message said:

What happens to each end of such double-length spokes? And
what does the rim do?

Their explanation on the tech web site:

# WHAT HAPPENS IF I BREAK A SPOKE ?

# The Kevlar / carbon fiber combination produces an
# incredibly strong and tough spoke. Under normal use, it is
# virtually impossible to break the fibers in a Topolino
# spoke. Topolino spokes are not subject to flex fatigue
# like steel spokes, because they cannot move where they
# join the hub and do not experience the bend and squirm
# associated with conventional steel spokes. A small nick in
# the spoke should normally be no problem. If a spoke ever
# does somehow fail, half of the spokes and one side of the
# hub are removed and replaced as one modular piece.
# Although not as inexpensive as a traditional steel spoke,
# the process is relatively straightforward (no special
# tools) and these "halves" are provided at a very
# reasonable cost.

Quoted message said:

Do rim-to-rim spokes work differently than traditional god-
fearing rim-to-hub spokes? Was this all tried years ago,
worked out, and abandoned?

They must be anchored at the hub or it wouldn't be
supported. If, as is implied in one of their pictures, the
hub hangs in a hammock of a slightly angled spoke pair, then
the wheel would be unstable and collapse the rim from the
extreme tension this would cause in a horizontal spoke
(pair). If I happen to see one of these wheels, I'll
certainly give it my scrutiny.

Jobst Brandt [email hidden]

Quoted post said:

Originally posted by Jobst Brandt

BCarl Fogel said:

As I understand things, a normal pre-tensioned bicycle
wheel "stands" [1] on its lower spokes, which lose tension
as they roll under the hub, effectively compressing, while
the other spokes show no significant change in tension.

Quoted message said:

At the same time, the bottom of the rim flattens out a
tiny bit.

Quoted message said:

So how do these odd wheels work?

Quoted message said:

topolinotech.comtopolinotech.comOpen ↗

Quoted message said:

topolinotech.comWheelSpokes.htmOpen ↗

Neither the pictures nor the text make this clear to me.
However, I notice that the spokes are anchored to each other
at their crossings. The whole concept reeks of "it's
different and therefore good".

Quoted message said:

They seem to bend double-length spokes slightly around the
hub, from one side of the rim to the other.

Quoted message said:

What happens to each end of such double-length spokes? And
what does the rim do?

Their explanation on the tech web site:

# WHAT HAPPENS IF I BREAK A SPOKE ?

# The Kevlar / carbon fiber combination produces an
# incredibly strong and tough spoke. Under normal use, it is
# virtually impossible to break the fibers in a Topolino
# spoke. Topolino spokes are not subject to flex fatigue
# like steel spokes, because they cannot move where they
# join the hub and do not experience the bend and squirm
# associated with conventional steel spokes. A small nick in
# the spoke should normally be no problem. If a spoke ever
# does somehow fail, half of the spokes and one side of the
# hub are removed and replaced as one modular piece.
# Although not as inexpensive as a traditional steel spoke,
# the process is relatively straightforward (no special
# tools) and these "halves" are provided at a very
# reasonable cost.

Quoted message said:

Do rim-to-rim spokes work differently than traditional god-
fearing rim-to-hub spokes? Was this all tried years ago,
worked out, and abandoned?

They must be anchored at the hub or it wouldn't be
supported. If, as is implied in one of their pictures, the
hub hangs in a hammock of a slightly angled spoke pair, then
the wheel would be unstable and collapse the rim from the
extreme tension this would cause in a horizontal spoke
(pair). If I happen to see one of these wheels, I'll
certainly give it my scrutiny.

Jobst Brandt [email hidden] [/B]

I weigh 120kg and can climb small but steep hills in the big ring with no real "Flex" or damage to the Topolino...I see in another post Nelson Vales has a pair, If he cant breack em......

Carl Fogel said:

As I understand things, a normal pre-tensioned bicycle
wheel "stands" [1] on its lower spokes, which lose tension
as they roll under the hub, effectively compressing, while
the other spokes show no significant change in tension.

At the same time, the bottom of the rim flattens out a
tiny bit.

So how do these odd wheels work?

topolinotech.comtopolinotech.comOpen ↗

topolinotech.comWheelSpokes.htmOpen ↗

They seem to bend double-length spokes slightly around the
hub, from one side of the rim to the other.

What happens to each end of such double-length spokes? And
what does the rim do?

Do rim-to-rim spokes work differently than traditional god-
fearing rim-to-hub spokes? Was this all tried years ago,
worked out, and abandoned?

Dear Carl,

Topolino is the Italian name for Mickey Mouse. That would
suggest that these wheels are designed using "Mickey Mouse
Engineering".

--
Tom Sherman - Quad Cities (Illinois Side)

On 19 Mar 2004 19:01:56 -0800, [email hidden] (Carl Fogel) may

have said:

So how do these odd wheels work?

topolinotech.comtopolinotech.comOpen ↗

topolinotech.comWheelSpokes.htmOpen ↗

By distribution of the loading via tension, the same as a
regular wheel.

Quoted message said:

They seem to bend double-length spokes slightly around the
hub, from one side of the rim to the other.

It appears that the spokes are bonded in place where they go
through their channel in the hub as well. The manufacturer's
statement about the spoke replacement procedure makes this
fairly clear: "If a spoke ever does somehow fail, half of
the spokes and one side of the hub are removed and replaced
as one modular piece."

In other words, just because the spoke filaments continue
from nipple to nipple does not mean that the spoke is not
effectively attached to the hub at the center.

Quoted message said:

What happens to each end of such double-length spokes? And
what does the rim do?

The spokes and rim do the same thing they always do, just
using different materials than are ordinarily employed.

Quoted message said:

Do rim-to-rim spokes work differently than traditional god-
fearing rim-to-hub spokes?

Since the illusion that the spokes somehow are not anchored
to the hub has been punctured, the question is no longer
meaningful.

Quoted message said:

Was this all tried years ago, worked out, and abandoned?

Probably, using different materials.

I'd also point out their lack of honesty in another
statement; "steel is 3 times stiffer than aluminum", which
only works if you are comparing a steel part that's stiffer
than an equivalent aluminum part that's been made to be less
stiff than the steel one. Stiffness is in the heat treating
and alloy selection; aluminum can be very stiff indeed.

To me, this is an example of stupid-light tech
accomplishing a well-understood task in a novel but not real-world-
useful manner. I, for one, would not want to rely on a
design that required the exchange of nearly half of the
complete assembly in the event that a spoke was damaged. A
steel spoke is easily swapped out, and its failure is a
relatively trivial matter in a well-designed wheel. These
Topolino wheels holds no fascination whatever for me;
doubtless there will be people who will be enchanted by the
novelty, though, and they are welcome to them. I don't
doubt that the wheels *work*, I just can't find anything in
them that appeals to me.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

Werehatrack said:

... I'd also point out their lack of honesty in another
statement; "steel is 3 times stiffer than aluminum", which
only works if you are comparing a steel part that's
stiffer than an equivalent aluminum part that's been made
to be less stiff than the steel one. Stiffness is in the
heat treating and alloy selection; aluminum can be very
stiff indeed....

They should use the term elastic (or Young's) modulus to
avoid confusion over whether they are referring to the
intrinsic material property, or that of a particular section
of the material under loading.

The elastic modulus of aluminium is around 75 GPa, while
that of steel is around 200 GPa, so the elastic modulus of
steel is roughly 3 times that of aluminium.

While the tensile strength of both aluminium and steel will
vary widely with alloying, cold working and heat treatment,
the elastic moduli do not change significantly.

--
Tom Sherman - Quad Cities (Illinois Side)

Quoted message said:

Neither the pictures nor the text make this clear to me.
However, I notice that the spokes are anchored to each
other at their crossings. The whole concept reeks of "it's
different and therefore good".

It must remove the problem of spokes breaking at the bends,
because there aren't any sharp bends at all.

I think I'd trade the occasional breakage on a conventional
wheel against the undoubtedly massive repair costs if one
of these things needs attention. The need to replace half
the hub and spokes, not a LBS job, suggests it's a
throwaway design.

I always thought the hub was suspended from all the spokes
simultaneously ("A suspension bridge with no end-points" as
an engineer once put it)?

- - "May you have the wind at your back. And a really low
gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner geocities.comczcornerOpen ↗

"Chris Zacho "The Wheelman"" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I always thought the hub was suspended from all the spokes
simultaneously ("A suspension bridge with no end-points"
as an engineer once put it)?

Yes, that's about it. But the tension decrease is not linear
across all spokes (or pre-tensioned members in this case..)
when a load is introduced at the hub. The bottom few spokes
have greater reduced tension and the rest are increased by a
much smaller amount. But you're right, it is being suspended
by all spokes simultaneously.

Cheers,

Scott..