On 1/14/2022 11:23 AM, Tom Kunich wrote:
> On Thursday, January 13, 2022 at 5:41:38 PM UTC-8, Ralph Barone wrote:
>> Frank Krygowski <frkr...@sbcglobal.net> wrote:
>>> On 1/13/2022 3:43 PM, Roger Merriman wrote:
>>>> Frank Krygowski <frkr...@sbcglobal.net> wrote:
>>>>> On 1/13/2022 1:26 PM, AMuzi wrote:
>>>>>> woo hoo the future is here, maybe:
>>>>>>
>>>>>> https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
>>>>>>
>>>>>>
>>>>> Wow. Talk about diminishing returns!
>>>>>
>>>>
>>>> I’m assuming Frank is talking about any performance gain which I agree
>>>> seems to be into undetectable levels!
>>>
>>> Yes, exactly.
>>>
>>> The friction drag from ordinary pawls is so low as to be practically
>>> undetectable. It may be that eddy current losses from those tiny magnets
>>> more than offset any purported improvement.
>>>
>>> Just imagine the chagrin of the owner of _this_ year's hub, when he
>>> realizes his buddy with _last_ year's hub is coasting one nanometer per
>>> second faster than he is. Because, no eddy currents! ;-)
>>>
>>>
>> The funny trying is that to a first approximation, you would assume that
>> the force the magnets are placing on the pawls would be the same as that
>> from the previous spring design, so the friction should be the same. The
>> force from the magnets should be more non-linear than that from springs, so
>> maybe that counts for something, but when you’re talking about second order
>> effects on something that is in itself a second order effect, yeah, it’s
>> gonna be tiny.
>
> Super magnets which would be necessary in a design like this are sensitive to harsh vibration so I wouldn't even try them.
>

It's not ridiculous.
Clearances are small and the outer ratchet ring is steel.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On Friday, January 14, 2022 at 9:48:23 AM UTC-8, AMuzi wrote:
> On 1/14/2022 11:23 AM, Tom Kunich wrote:
> > On Thursday, January 13, 2022 at 5:41:38 PM UTC-8, Ralph Barone wrote:
> >> Frank Krygowski <frkr...@sbcglobal.net> wrote:
> >>> On 1/13/2022 3:43 PM, Roger Merriman wrote:
> >>>> Frank Krygowski <frkr...@sbcglobal.net> wrote:
> >>>>> On 1/13/2022 1:26 PM, AMuzi wrote:
> >>>>>> woo hoo the future is here, maybe:
> >>>>>>
> >>>>>> https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
> >>>>>>
> >>>>>>
> >>>>> Wow. Talk about diminishing returns!
> >>>>>
> >>>>
> >>>> I’m assuming Frank is talking about any performance gain which I agree
> >>>> seems to be into undetectable levels!
> >>>
> >>> Yes, exactly.
> >>>
> >>> The friction drag from ordinary pawls is so low as to be practically
> >>> undetectable. It may be that eddy current losses from those tiny magnets
> >>> more than offset any purported improvement.
> >>>
> >>> Just imagine the chagrin of the owner of _this_ year's hub, when he
> >>> realizes his buddy with _last_ year's hub is coasting one nanometer per
> >>> second faster than he is. Because, no eddy currents! ;-)
> >>>
> >>>
> >> The funny trying is that to a first approximation, you would assume that
> >> the force the magnets are placing on the pawls would be the same as that
> >> from the previous spring design, so the friction should be the same. The
> >> force from the magnets should be more non-linear than that from springs, so
> >> maybe that counts for something, but when you’re talking about second order
> >> effects on something that is in itself a second order effect, yeah, it’s
> >> gonna be tiny.
> >
> > Super magnets which would be necessary in a design like this are sensitive to harsh vibration so I wouldn't even try them.
> >
> It's not ridiculous.
> Clearances are small and the outer ratchet ring is steel.

Well, my experience with super magnets was mostly in starter motors. They ALL fail sooner or later whereas the older all DC drives were good forever.

On Fri, 14 Jan 2022 11:48:25 -0600, AMuzi <am@yellowjersey.org> wrote:

>On 1/14/2022 11:23 AM, Tom Kunich wrote:
>> On Thursday, January 13, 2022 at 5:41:38 PM UTC-8, Ralph Barone wrote:
>>> Frank Krygowski <frkr...@sbcglobal.net> wrote:
>>>> On 1/13/2022 3:43 PM, Roger Merriman wrote:
>>>>> Frank Krygowski <frkr...@sbcglobal.net> wrote:
>>>>>> On 1/13/2022 1:26 PM, AMuzi wrote:
>>>>>>> woo hoo the future is here, maybe:
>>>>>>>
>>>>>>> https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
>>>>>>>
>>>>>>>
>>>>>> Wow. Talk about diminishing returns!
>>>>>>
>>>>>
>>>>> I’m assuming Frank is talking about any performance gain which I agree
>>>>> seems to be into undetectable levels!
>>>>
>>>> Yes, exactly.
>>>>
>>>> The friction drag from ordinary pawls is so low as to be practically
>>>> undetectable. It may be that eddy current losses from those tiny magnets
>>>> more than offset any purported improvement.
>>>>
>>>> Just imagine the chagrin of the owner of _this_ year's hub, when he
>>>> realizes his buddy with _last_ year's hub is coasting one nanometer per
>>>> second faster than he is. Because, no eddy currents! ;-)
>>>>
>>>>
>>> The funny trying is that to a first approximation, you would assume that
>>> the force the magnets are placing on the pawls would be the same as that
>>> from the previous spring design, so the friction should be the same. The
>>> force from the magnets should be more non-linear than that from springs, so
>>> maybe that counts for something, but when you’re talking about second order
>>> effects on something that is in itself a second order effect, yeah, it’s
>>> gonna be tiny.
>>
>> Super magnets which would be necessary in a design like this are sensitive to harsh vibration so I wouldn't even try them.
>>
>
>It's not ridiculous.
>Clearances are small and the outer ratchet ring is steel.

But, but, but. this morning's news has it that the use of these exotic
super magnets, unless manufactured from U.S. "Rare Earths", is, or is
going to be, illegal. NO MORE CHINESE RARE EARTHS!
https://www.aljazeera.com/news/2022/1/14/us-bill-would-block-defence-firms-from-using-chinese-rare
Never mind that the U.S. currently has only one rare-earths mine and
has no capacity to process rare-earth minerals.
--
Cheers,

John B.

On Fri, 14 Jan 2022 09:25:22 -0800 (PST), Tom Kunich
<cyclintom@gmail.com> wrote:

>On Thursday, January 13, 2022 at 9:25:57 PM UTC-8, jeff.li...@gmail.com wrote:
>> On Thu, 13 Jan 2022 12:26:49 -0600, AMuzi <a...@yellowjersey.org> wrote:
>>
>> >woo hoo the future is here, maybe:
>> >https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
>> I don't understand the benefits of magnets. Slightly faster shifting?
>>
>> Magnetic attraction (force) is proportional to the square of the
>> distance, while spring force is directly proportional (linear) with
>> the compression/expansion distance. A magnet can create quite a bit
>> of force over fairly small distances, but inverse square law soon
>> makes the force weak over a larger distance. In other words, it would
>> be like the magnetic "spring" wasn't even there if the pawl need to
>> move a moderate distance. Magnetism also has a hysteresis effect,
>> where it takes more force to separate the magnet(s) than it does to
>> attract the magnet(s). I can only imagine the problems caused by the
>> magnets attracting iron filings from sand and road grit. Unless I'm
>> missing something here, magnets seem to offer additional complications
>> over a simple spring, and minimal benefits. I'm I missing something
>> somewhere?

>Jeff, you are correct. But you don't actually believe this difference to make any measurable difference in rotational energy demand do you?

I do wish you would stop telling me what I "believe" and then ask me
to defend *YOUR* position. You could have just asked me if I believe
that there was any measurable difference in what "rotational energy
demand" might be. Had you done that I would have pointed out that it
should be "rotational kinetic energy" and that it is not a "demand"
system, which might mean reducing the energy required to power the
hub. Note that the calculation of "rotational kinetic energy"
involves the angular velocity of the hub (also known as RPM), and the
moment of inertia about the axle, which is a function of the radial
mass distribution of the hub:
<https://en.wikipedia.org/wiki/Rotational_energy>
Since the RPM doesn't change with the new design, and most of the
rotational mass of the hub is in the sprockets, there will be little
or no change in the "rotational kinetic energy" of the hub with a
change of mass, spring action, or design of the pawls.

I haven't had time to check if there is a patent application on the
design. Since I still don't understand how replacing a spring with a
magnet to possibly produce "faster engagement", I'm hoping to find a
better explanation in the patent application. Until then, color me
neutral, uninformed, and skeptical about the device. If there was a
change of mass (i.e. less weight) or mass distribution (moment of
inertia), it may have been negated by the addition of more lubricating
oil:
<https://bikerumor.com/nahbs-2017-project-321-introduces-low-drag-high-engagement-magnetic-drive-system-quiet-loud-choice/>
"Project 321 actually increased the oil volume by adding
a bunch of machined holes under the driver in the hub shell."
Is the additional oil necessary for some improvement, besides sound
dampening and decreased service interval, or is something wearing out
quicker which requires lubrication. I don't know and I'm suspicious.

--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On Saturday, January 15, 2022 at 10:01:49 AM UTC-8, jeff.li...@gmail.com wrote:
> On Fri, 14 Jan 2022 09:25:22 -0800 (PST), Tom Kunich
> <cycl...@gmail.com> wrote:
>
> >On Thursday, January 13, 2022 at 9:25:57 PM UTC-8, jeff.li...@gmail.com wrote:
> >> On Thu, 13 Jan 2022 12:26:49 -0600, AMuzi <a...@yellowjersey.org> wrote:
> >>
> >> >woo hoo the future is here, maybe:
> >> >https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
> >> I don't understand the benefits of magnets. Slightly faster shifting?
> >>
> >> Magnetic attraction (force) is proportional to the square of the
> >> distance, while spring force is directly proportional (linear) with
> >> the compression/expansion distance. A magnet can create quite a bit
> >> of force over fairly small distances, but inverse square law soon
> >> makes the force weak over a larger distance. In other words, it would
> >> be like the magnetic "spring" wasn't even there if the pawl need to
> >> move a moderate distance. Magnetism also has a hysteresis effect,
> >> where it takes more force to separate the magnet(s) than it does to
> >> attract the magnet(s). I can only imagine the problems caused by the
> >> magnets attracting iron filings from sand and road grit. Unless I'm
> >> missing something here, magnets seem to offer additional complications
> >> over a simple spring, and minimal benefits. I'm I missing something
> >> somewhere?
>
> >Jeff, you are correct. But you don't actually believe this difference to make any measurable difference in rotational energy demand do you?
> I do wish you would stop telling me what I "believe" and then ask me
> to defend *YOUR* position. You could have just asked me if I believe
> that there was any measurable difference in what "rotational energy
> demand" might be. Had you done that I would have pointed out that it
> should be "rotational kinetic energy" and that it is not a "demand"
> system, which might mean reducing the energy required to power the
> hub. Note that the calculation of "rotational kinetic energy"
> involves the angular velocity of the hub (also known as RPM), and the
> moment of inertia about the axle, which is a function of the radial
> mass distribution of the hub:
> <https://en.wikipedia.org/wiki/Rotational_energy>
> Since the RPM doesn't change with the new design, and most of the
> rotational mass of the hub is in the sprockets, there will be little
> or no change in the "rotational kinetic energy" of the hub with a
> change of mass, spring action, or design of the pawls.
>
> I haven't had time to check if there is a patent application on the
> design. Since I still don't understand how replacing a spring with a
> magnet to possibly produce "faster engagement", I'm hoping to find a
> better explanation in the patent application. Until then, color me
> neutral, uninformed, and skeptical about the device. If there was a
> change of mass (i.e. less weight) or mass distribution (moment of
> inertia), it may have been negated by the addition of more lubricating
> oil:
> <https://bikerumor.com/nahbs-2017-project-321-introduces-low-drag-high-engagement-magnetic-drive-system-quiet-loud-choice/>
> "Project 321 actually increased the oil volume by adding
> a bunch of machined holes under the driver in the hub shell."
> Is the additional oil necessary for some improvement, besides sound
> dampening and decreased service interval, or is something wearing out
> quicker which requires lubrication. I don't know and I'm suspicious.

If you don't like the way the question is posed why do you feel the orgasmic need to answer?

On 1/13/2022 10:26 AM, AMuzi wrote:
> woo hoo the future is here, maybe:
>
> https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/

Magnetic hubs were first available in 2008, as far as I can tell
<https://www.blackcatwheels.ch/2018/05/soul-kozak-hubs-truly-first-and.html>.

They've never caught on. They are an answer to a question that nobody asked.

On Fri, 14 Jan 2022 02:50:31 -0800 (PST), "funkma...@hotmail.com"
<funkmasterxx@hotmail.com> wrote:

>On Friday, January 14, 2022 at 12:25:57 AM UTC-5, jeff.li...@gmail.com wrote:
>> On Thu, 13 Jan 2022 12:26:49 -0600, AMuzi <a...@yellowjersey.org> wrote:
>>
>> >woo hoo the future is here, maybe:
>> >https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
>> I don't understand the benefits of magnets. Slightly faster shifting?

>No, faster engagement (allegedly)

It's been done before. The Project321 hub claims 1.67 degree angle
(215 points of engagement). There are other hubs that go as low as
1.5 degrees (240 points). See Table 1 at:
<https://cyclingtips.com/2018/12/hub-tech-understanding-freehubs-and-points-of-engagement/>
There's even zero degrees using a roller clutch mechanism.

In theory, the minimum engagement time is the time it takes to rotate
though 1 point of engagement. At 15 mph (24.1 km/hr) the time for the
wheel to rotate past one point of engagement on the Project321 hub and
26" wheel is:
<https://endless-sphere.com/forums/viewtopic.php?t=16114>
60sec/min / 194rpm = 310 msec/revolution
With 215 points of engagement, that's
310 / 215 = 1.44 msec/points-of-engagement

Using another hub from Table 1 such as Camagnola with 30 points of
engagement, that would be:
310 / 30 = 10.3 msec/points-of-engagement

While that would be almost 15 times faster engagement time, it's still
only about 9 msec faster. If a rider furiously shifts perhaps 20
times per km, that would potentially be a maximum improvement of:
9msec * 20shifts/km = 180 msec/km
For a 5km race, that's a potential maximum improvement of 900msec or
about 1 second when comparing the two hubs. Is this really
worthwhile?

>That didn't quite make sense to me either, but I don't have enough of a background in magnetics to say it's not a good design. They _are_ using neodymium magnets, so the distance I found a BikeRumor article that addresses that point specifically, though they claim it's a benefit.
>https://bikerumor.com/nahbs-2017-project-321-introduces-low-drag-high-engagement-magnetic-drive-system-quiet-loud-choice/

Nice article. Thanks.

>Coil springs generally have linear compression force, but many hubs use a flat pawl spring which have a progressive rate (https://www.ebay.com/p/2254408269, these are the ones that tend to break). It would Seem like you would _want_ an easier disengagement and and something that pushes back harder the more you push it away, rather the other way around something that has a non-linear reduction in force. , so you have a good point here IMO.

I blundered across the SRAM Zipp 404 wheel and hub, which uses an
axial (in line with axle) magnetic clutch mechanism:
<https://cyclingtips.com/2016/10/zipp-404-nsw-carbon-clincher-wheelset-review/>
What's different is that the clutch completely disengages while
coasting. Therefore, there's no drag (and no noise) from the pawls
while coasting. I didn't find a tooth count, but from the photos, I
think it's high enough to have a fairly short engagement time.
Offhand, it seems like a better way to do it.

> > I can only imagine the problems caused by the
>> magnets attracting iron filings from sand and road grit.

>That's something I hadn't considered, but could be reasonably mitigated with a good seal.

It's probably well sealed, especially since the article mentions that
there's extra oil in the hub. However, I'm always suspicious of
"waterproof" and "sealed" designs. In my experience designing marine
radios, neither of these are really true unless the package is
pressurized (with nitrogen or dried air).

>> Unless I'm
>> missing something here, magnets seem to offer additional complications
>> over a simple spring, and minimal benefits. I'm I missing something
>> somewhere?

>From a FMEA point of view, generally speaking fewer parts means fewer possible points of failure, but a complete FMEA would also look at something like the ability of a system to seal out contaminants that would cause wear/failure. Seal performance is something that's pretty difficult to model though, so in order to get a real sense of reliability you would need to perform environmental testing (which in my case also includes HALT). I could be wrong, but I don't think bicycle hub manufacturers are FMEA or environmental testing (let alone HALT), though some large company like shimano might be putting some money into a lab endurance test.

I suspect the hub would be used mostly for racing. The ideal
component would fall apart immediately after crossing the finish line.
Designing, simulating, and testing for long life is difficult enough.
Simulating and testing for a limited lifetime, presumably with some
safety margin (3x ??), is going to be a major effort. The biggest
variables for this are not easily modeled (road conditions, weather,
proper adjustment, etc).

What I think is happening is that the UCI established a lower limit of
6.8kg (15 lb) about 20 years ago. With carbon fiber, 6.8kg is easily
achieved. With weight no longer being a major consideration, bicycle
component designers seem to be targeting reduced friction and
optimizing timing.

--
Jeff Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On 1/16/2022 3:39 AM, Jeff Liebermann wrote:
>
> In theory, the minimum engagement time is the time it takes to rotate
> though 1 point of engagement. At 15 mph (24.1 km/hr) the time for the
> wheel to rotate past one point of engagement on the Project321 hub and
> 26" wheel is:
> <https://endless-sphere.com/forums/viewtopic.php?t=16114>
> 60sec/min / 194rpm = 310 msec/revolution
> With 215 points of engagement, that's
> 310 / 215 = 1.44 msec/points-of-engagement
>
> Using another hub from Table 1 such as Camagnola with 30 points of
> engagement, that would be:
> 310 / 30 = 10.3 msec/points-of-engagement
>
> While that would be almost 15 times faster engagement time, it's still
> only about 9 msec faster. If a rider furiously shifts perhaps 20
> times per km, that would potentially be a maximum improvement of:
> 9msec * 20shifts/km = 180 msec/km
> For a 5km race, that's a potential maximum improvement of 900msec or
> about 1 second when comparing the two hubs. Is this really
> worthwhile?
> ...
>
> What I think is happening is that the UCI established a lower limit of
> 6.8kg (15 lb) about 20 years ago. With carbon fiber, 6.8kg is easily
> achieved. With weight no longer being a major consideration, bicycle
> component designers seem to be targeting reduced friction and
> optimizing timing.

Or, probably more important to them, product differentiation.

Not to mention ever diminishing returns.

--
- Frank Krygowski

On 1/16/2022 10:31 AM, Frank Krygowski wrote:
> On 1/16/2022 3:39 AM, Jeff Liebermann wrote:
>>
>> In theory, the minimum engagement time is the time it
>> takes to rotate
>> though 1 point of engagement. At 15 mph (24.1 km/hr) the
>> time for the
>> wheel to rotate past one point of engagement on the
>> Project321 hub and
>> 26" wheel is:
>> <https://endless-sphere.com/forums/viewtopic.php?t=16114>
>> 60sec/min / 194rpm = 310 msec/revolution
>> With 215 points of engagement, that's
>> 310 / 215 = 1.44 msec/points-of-engagement
>>
>> Using another hub from Table 1 such as Camagnola with 30
>> points of
>> engagement, that would be:
>> 310 / 30 = 10.3 msec/points-of-engagement
>>
>> While that would be almost 15 times faster engagement
>> time, it's still
>> only about 9 msec faster. If a rider furiously shifts
>> perhaps 20
>> times per km, that would potentially be a maximum
>> improvement of:
>> 9msec * 20shifts/km = 180 msec/km
>> For a 5km race, that's a potential maximum improvement of
>> 900msec or
>> about 1 second when comparing the two hubs. Is this really
>> worthwhile?
> > ...
>>
>> What I think is happening is that the UCI established a
>> lower limit of
>> 6.8kg (15 lb) about 20 years ago. With carbon fiber,
>> 6.8kg is easily
>> achieved. With weight no longer being a major
>> consideration, bicycle
>> component designers seem to be targeting reduced friction and
>> optimizing timing.
>
> Or, probably more important to them, product differentiation.
>
> Not to mention ever diminishing returns.
>
+1
Everything is light, almost everything works dependably,
there are no more fancy lug cuts or flashy chromework and so
on. Which means differentiation is more difficult to
achieve; the method is now a press release touting some
arcane feature and not delicate hand striping.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On Sunday, January 16, 2022 at 10:20:47 PM UTC+5:30, AMuzi wrote:
> On 1/16/2022 10:31 AM, Frank Krygowski wrote:
> > On 1/16/2022 3:39 AM, Jeff Liebermann wrote:
> >>
> >> In theory, the minimum engagement time is the time it
> >> takes to rotate
> >> though 1 point of engagement. At 15 mph (24.1 km/hr) the
> >> time for the
> >> wheel to rotate past one point of engagement on the
> >> Project321 hub and
> >> 26" wheel is:
> >> <https://endless-sphere.com/forums/viewtopic.php?t=16114>
> >> 60sec/min / 194rpm = 310 msec/revolution
> >> With 215 points of engagement, that's
> >> 310 / 215 = 1.44 msec/points-of-engagement
> >>
> >> Using another hub from Table 1 such as Camagnola with 30
> >> points of
> >> engagement, that would be:
> >> 310 / 30 = 10.3 msec/points-of-engagement
> >>
> >> While that would be almost 15 times faster engagement
> >> time, it's still
> >> only about 9 msec faster. If a rider furiously shifts
> >> perhaps 20
> >> times per km, that would potentially be a maximum
> >> improvement of:
> >> 9msec * 20shifts/km = 180 msec/km
> >> For a 5km race, that's a potential maximum improvement of
> >> 900msec or
> >> about 1 second when comparing the two hubs. Is this really
> >> worthwhile?
> > > ...
> >>
> >> What I think is happening is that the UCI established a
> >> lower limit of
> >> 6.8kg (15 lb) about 20 years ago. With carbon fiber,
> >> 6.8kg is easily
> >> achieved. With weight no longer being a major
> >> consideration, bicycle
> >> component designers seem to be targeting reduced friction and
> >> optimizing timing.
> >
> > Or, probably more important to them, product differentiation.
> >
> > Not to mention ever diminishing returns.
> >
> +1
> Everything is light, almost everything works dependably,
> there are no more fancy lug cuts or flashy chromework and so
> on. Which means differentiation is more difficult to
> achieve; the method is now a press release touting some
> arcane feature and not delicate hand striping.
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971
https://www.emergenresearch.com/industry-report/computer-aided-design-market

On Wednesday, April 27, 2022 at 6:52:56 AM UTC-7, purushottam gaurav wrote:
> On Sunday, January 16, 2022 at 10:20:47 PM UTC+5:30, AMuzi wrote:
> > On 1/16/2022 10:31 AM, Frank Krygowski wrote:
> > > On 1/16/2022 3:39 AM, Jeff Liebermann wrote:
> > >>
> > >> In theory, the minimum engagement time is the time it
> > >> takes to rotate
> > >> though 1 point of engagement. At 15 mph (24.1 km/hr) the
> > >> time for the
> > >> wheel to rotate past one point of engagement on the
> > >> Project321 hub and
> > >> 26" wheel is:
> > >> <https://endless-sphere.com/forums/viewtopic.php?t=16114>
> > >> 60sec/min / 194rpm = 310 msec/revolution
> > >> With 215 points of engagement, that's
> > >> 310 / 215 = 1.44 msec/points-of-engagement
> > >>
> > >> Using another hub from Table 1 such as Camagnola with 30
> > >> points of
> > >> engagement, that would be:
> > >> 310 / 30 = 10.3 msec/points-of-engagement
> > >>
> > >> While that would be almost 15 times faster engagement
> > >> time, it's still
> > >> only about 9 msec faster. If a rider furiously shifts
> > >> perhaps 20
> > >> times per km, that would potentially be a maximum
> > >> improvement of:
> > >> 9msec * 20shifts/km = 180 msec/km
> > >> For a 5km race, that's a potential maximum improvement of
> > >> 900msec or
> > >> about 1 second when comparing the two hubs. Is this really
> > >> worthwhile?
> > > > ...
> > >>
> > >> What I think is happening is that the UCI established a
> > >> lower limit of
> > >> 6.8kg (15 lb) about 20 years ago. With carbon fiber,
> > >> 6.8kg is easily
> > >> achieved. With weight no longer being a major
> > >> consideration, bicycle
> > >> component designers seem to be targeting reduced friction and
> > >> optimizing timing.
> > >
> > > Or, probably more important to them, product differentiation.
> > >
> > > Not to mention ever diminishing returns.
> > >
> > +1
> > Everything is light, almost everything works dependably,
> > there are no more fancy lug cuts or flashy chromework and so
> > on. Which means differentiation is more difficult to
> > achieve; the method is now a press release touting some
> > arcane feature and not delicate hand striping.
> > --
> > Andrew Muzi
> > <www.yellowjersey.org/>
> > Open every day since 1 April, 1971
> https://www.emergenresearch.com/industry-report/computer-aided-design-market

As someone who used CAD as it was developed I can say that the trouble with it is that it reduces the requirement for intellectual curiosity in trade for more rapid development of set systemic development. Smartphones being a capital example. But believing that you can invent things via CAD is a grave mistake. The last job I had, had the basic microprocessor hardware designed with CAD and since they didn't input the entire requirements, it was improperly designed. This ended that project when I told them that it didn't have an interrupt for the RF link.

I had been hired to write the firmware so until I reached that point in the firmware development I didn't bother to look for that since it had been supposedly designed by a competent engineer using CAD. And since he had no idea of the system with which the firmware would be written he couldn't foresee that it had to be built around a real time operating system requiring everything to work via interrupts.

So, CAD is useful for development of things you already know. It is not for unknown requirements. I spent 50 years doing this stuff and get tired of people telling me about it who are not engineers nor think like one. You appear to be a financial advisor and are merely following market trends whereas the market is being limited by the very thing presently in rapid growth.