woo hoo the future is here, maybe:

https://cyclingtips.com/2022/01/stans-notubes-partners-with-project321-for-new-m-pulse-magnetic-hubs/
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

On Thursday, January 13, 2022 at 7:26:50 PM UTC+1, 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/
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971

Not Nobel prize material, but clever. Just replaced a broken spring leaf in my Zipp hub. I prefer the DT240S solution.

Lou

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!

--
- Frank Krygowski

On Thursday, January 13, 2022 at 1:26:50 PM UTC-5, 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/
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971

I'm not in the market for new wheels right now, but this seems at least very interesting. I don't think the point of the magnets was for increased speed, rather, faster and more positive engagement? The pawl profile is the same style they've used for 5 years, which they boast has 68% less drag than other designs. Whether 68% less drag on the pawls is enough of a change to make you go faster is probably dubious for anywhere except a lab test - sort of like increased drag from chain alignment has any real-world effect.

When I first read your post I thought it was a new magnetically suspended frictionless bearing application.

On Thursday, January 13, 2022 at 2:45:55 PM UTC-5, Frank Krygowski 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!
>

How so? In terms of cost they're on par with other high-end hubs, actually cheaper than Swiss DT-240 EXP and Chris King R45.

Frank Krygowski <frkrygow@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!

I’d also say that I generally like bike parts to be repairable by a bike
shop.

My old commute beastie due to the miles it does plus the terrain, need all
manner of things replaced, it’s a bit sluggish engaging at moment so will
get shop to look at it as and when it next needs their talents!

Roger Merriman

On Thursday, January 13, 2022 at 3:43:30 PM UTC-5, 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!

I was assuming he was referring to the Law of Diminishing Returns - which I can concede would seemingly apply to _any_ hub in that price range. However, There are many more expensive hubs out there, so generally speaking I wouldn't personally say that this product is noteworthy in that context.

>
> I’d also say that I generally like bike parts to be repairable by a bike
> shop.

OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.

Seriously though, this design is actually more simple since there are _no_ springs (I did find a broken pawl spring once or twice). So unless the magnet somehow dislodges, it would seem the failure rate of this design is at least theoretically lower than a standard sprung pawl design.

>
> My old commute beastie due to the miles it does plus the terrain, need all
> manner of things replaced, it’s a bit sluggish engaging at moment so will
> get shop to look at it as and when it next needs their talents!
>
> Roger Merriman

On 1/13/2022 3:43 PM, Roger Merriman wrote:
> Frank Krygowski <frkrygow@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! ;-)

--
- Frank Krygowski

On 1/13/2022 3:58 PM, funkma...@hotmail.com wrote:
>
> OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.

I've been told the technical name for such a component is a "ping-f**kit"

And I deal with them surprisingly often. In fact, I think scientists
should be working to identify whatever causes small mechanical bits to
spontaneously eject and become invisible.

Maybe someone's already done that and scaled it up! This could be what's
behind Unidentified Aerial Phenomena!

--
- Frank Krygowski

On Thursday, January 13, 2022 at 4:10:29 PM UTC-5, Frank Krygowski 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! ;-)
>
Now you're thinking - could be an Eddy Current Compensation Module in the next version.....I'd say they could market that right next to the Metric Torx set.

On Thursday, January 13, 2022 at 4:19:40 PM UTC-5, Frank Krygowski wrote:
> On 1/13/2022 3:58 PM, funkma...@hotmail.com wrote:
> >
> > OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.
> I've been told the technical name for such a component is a "ping-f**kit"

I like it. Now to market the "Pingfuckit Retriever" alongside the Eddy Current Compensation Module and the Metric Torx set.

>
> And I deal with them surprisingly often. In fact, I think scientists
> should be working to identify whatever causes small mechanical bits to
> spontaneously eject and become invisible.

There are well-known corollaries to Murphy's Law addressing this:
- The smaller the part, the more important it is
- The smaller the part, the farther away it will land when dropped.
- A lost part will reappear in an obvious place after you're purchased and installed a new one.
The obviousness is directly proportional to the factor of (the cost of the replacement * the length of time it took to receive it) ^the time it took to replace it

On 1/13/2022 3:56 PM, funkma...@hotmail.com wrote:
> On Thursday, January 13, 2022 at 4:19:40 PM UTC-5, Frank Krygowski wrote:
>> On 1/13/2022 3:58 PM, funkma...@hotmail.com wrote:
>>>
>>> OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.
>> I've been told the technical name for such a component is a "ping-f**kit"
>
> I like it. Now to market the "Pingfuckit Retriever" alongside the Eddy Current Compensation Module and the Metric Torx set.
>
>>
>> And I deal with them surprisingly often. In fact, I think scientists
>> should be working to identify whatever causes small mechanical bits to
>> spontaneously eject and become invisible.
>
> There are well-known corollaries to Murphy's Law addressing this:
> - The smaller the part, the more important it is
> - The smaller the part, the farther away it will land when dropped.
> - A lost part will reappear in an obvious place after you're purchased and installed a new one.
> The obviousness is directly proportional to the factor of (the cost of the replacement * the length of time it took to receive it) ^the time it took to replace it
>

Shop floors are permeable to small parts but the phenomenon
is directional; they go right through but they don't ever
come back up.

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

On Thursday, January 13, 2022 at 2:07:19 PM UTC-8, AMuzi wrote:
> On 1/13/2022 3:56 PM, funkma...@hotmail.com wrote:
> > On Thursday, January 13, 2022 at 4:19:40 PM UTC-5, Frank Krygowski wrote:
> >> On 1/13/2022 3:58 PM, funkma...@hotmail.com wrote:
> >>>
> >>> OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.
> >> I've been told the technical name for such a component is a "ping-f**kit"
> >
> > I like it. Now to market the "Pingfuckit Retriever" alongside the Eddy Current Compensation Module and the Metric Torx set.
> >
> >>
> >> And I deal with them surprisingly often. In fact, I think scientists
> >> should be working to identify whatever causes small mechanical bits to
> >> spontaneously eject and become invisible.
> >
> > There are well-known corollaries to Murphy's Law addressing this:
> > - The smaller the part, the more important it is
> > - The smaller the part, the farther away it will land when dropped.
> > - A lost part will reappear in an obvious place after you're purchased and installed a new one.
> > The obviousness is directly proportional to the factor of (the cost of the replacement * the length of time it took to receive it) ^the time it took to replace it
> >
> Shop floors are permeable to small parts but the phenomenon
> is directional; they go right through but they don't ever
> come back up.

I was assembling the Trek together and I loosened the stem and the fork fell out and the Cane Creek upper 41 x 39 mm bearing fell out and I spend an entire morning looking for it fruitlessly. This is the bearing that supposedly takes all of the turning forces so there should be replacements available. Cane Creek tells me the number is BAA1130 but I couldn't find that number on their site anywhere. Now the assembly of the Trek has frozen in place and because of all the time I wasted looking for that bearing, I didn't get out for the first ride on the Douglas Vector in its new setup. You absolutely must ride these tubeless tires for several miles so that they will hold air. But no such luck today.

funkma...@hotmail.com <funkmasterxx@hotmail.com> wrote:
> On Thursday, January 13, 2022 at 3:43:30 PM UTC-5, 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!
>
> I was assuming he was referring to the Law of Diminishing Returns - which
> I can concede would seemingly apply to _any_ hub in that price range.
> However, There are many more expensive hubs out there, so generally
> speaking I wouldn't personally say that this product is noteworthy in that context.
>
>>
>> I’d also say that I generally like bike parts to be repairable by a bike
>> shop.
>
> OH, c'mon roger, what fun is there in that? Don't you enjoy having to
> scour the shop floor looking for that one loose ball bearing or that
> lousy stinking derailleur stop screw you managed to drop? I've even had
> to break out the magnet bar for a pawl spring that lept out of the
> freehub assembly I was rebuilding and ended up ten feet away.
>
> Seriously though, this design is actually more simple since there are
> _no_ springs (I did find a broken pawl spring once or twice). So unless
> the magnet somehow dislodges, it would seem the failure rate of this
> design is at least theoretically lower than a standard sprung pawl design.

I’m not aware of the springs wearing or snapping but well the fact that the
hub will get water and mud ingress, and thus they do wear and need fixing
even on the commute I occasionally take the woods home which can be soggy
so all of the drive chain needs to be something that either I or bike shop
can fix and get parts for.

Which this technology doesn’t sound like it’s a good fit for, on a nice
road bike that only comes out on the club run? Sure.

Some technology doesn’t do well with over wet or gritty conditions.

Oddly the worse I had was a old technology, ie single speed ie BMX
freewheels will freeze up, and stop engaging. On a cold winters day in
london ie no so cold there isn’t some unfrozen water, it will get into the
hub freeze and stop it from engaging correctly…

>
>>
>> My old commute beastie due to the miles it does plus the terrain, need all
>> manner of things replaced, it’s a bit sluggish engaging at moment so will
>> get shop to look at it as and when it next needs their talents!
>>
>> Roger Merriman
>

Roger Merriman

On Thursday, January 13, 2022 at 3:28:32 PM UTC-8, Tom Kunich wrote:
> On Thursday, January 13, 2022 at 2:07:19 PM UTC-8, AMuzi wrote:
> > On 1/13/2022 3:56 PM, funkma...@hotmail.com wrote:
> > > On Thursday, January 13, 2022 at 4:19:40 PM UTC-5, Frank Krygowski wrote:
> > >> On 1/13/2022 3:58 PM, funkma...@hotmail.com wrote:
> > >>>
> > >>> OH, c'mon roger, what fun is there in that? Don't you enjoy having to scour the shop floor looking for that one loose ball bearing or that lousy stinking derailleur stop screw you managed to drop? I've even had to break out the magnet bar for a pawl spring that lept out of the freehub assembly I was rebuilding and ended up ten feet away.
> > >> I've been told the technical name for such a component is a "ping-f**kit"
> > >
> > > I like it. Now to market the "Pingfuckit Retriever" alongside the Eddy Current Compensation Module and the Metric Torx set.
> > >
> > >>
> > >> And I deal with them surprisingly often. In fact, I think scientists
> > >> should be working to identify whatever causes small mechanical bits to
> > >> spontaneously eject and become invisible.
> > >
> > > There are well-known corollaries to Murphy's Law addressing this:
> > > - The smaller the part, the more important it is
> > > - The smaller the part, the farther away it will land when dropped.
> > > - A lost part will reappear in an obvious place after you're purchased and installed a new one.
> > > The obviousness is directly proportional to the factor of (the cost of the replacement * the length of time it took to receive it) ^the time it took to replace it
> > >
> > Shop floors are permeable to small parts but the phenomenon
> > is directional; they go right through but they don't ever
> > come back up.
> I was assembling the Trek together and I loosened the stem and the fork fell out and the Cane Creek upper 41 x 39 mm bearing fell out and I spend an entire morning looking for it fruitlessly. This is the bearing that supposedly takes all of the turning forces so there should be replacements available. Cane Creek tells me the number is BAA1130 but I couldn't find that number on their site anywhere. Now the assembly of the Trek has frozen in place and because of all the time I wasted looking for that bearing, I didn't get out for the first ride on the Douglas Vector in its new setup. You absolutely must ride these tubeless tires for several miles so that they will hold air. But no such luck today.

That should have been 41 x 30 and the part number is BAA1130

Frank Krygowski <frkrygow@sbcglobal.net> wrote:
> On 1/13/2022 3:43 PM, Roger Merriman wrote:
>> Frank Krygowski <frkrygow@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.

On 1/13/2022 6:06 PM, Roger Merriman wrote:
> funkma...@hotmail.com <funkmasterxx@hotmail.com> wrote:
>> On Thursday, January 13, 2022 at 3:43:30 PM UTC-5, 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!
>>
>> I was assuming he was referring to the Law of Diminishing Returns - which
>> I can concede would seemingly apply to _any_ hub in that price range.
>> However, There are many more expensive hubs out there, so generally
>> speaking I wouldn't personally say that this product is noteworthy in that context.
>>
>>>
>>> I’d also say that I generally like bike parts to be repairable by a bike
>>> shop.
>>
>> OH, c'mon roger, what fun is there in that? Don't you enjoy having to
>> scour the shop floor looking for that one loose ball bearing or that
>> lousy stinking derailleur stop screw you managed to drop? I've even had
>> to break out the magnet bar for a pawl spring that lept out of the
>> freehub assembly I was rebuilding and ended up ten feet away.
>>
>> Seriously though, this design is actually more simple since there are
>> _no_ springs (I did find a broken pawl spring once or twice). So unless
>> the magnet somehow dislodges, it would seem the failure rate of this
>> design is at least theoretically lower than a standard sprung pawl design.
>
> I’m not aware of the springs wearing or snapping but well the fact that the
> hub will get water and mud ingress, and thus they do wear and need fixing
> even on the commute I occasionally take the woods home which can be soggy
> so all of the drive chain needs to be something that either I or bike shop
> can fix and get parts for.
>
> Which this technology doesn’t sound like it’s a good fit for, on a nice
> road bike that only comes out on the club run? Sure.
>
> Some technology doesn’t do well with over wet or gritty conditions.
>
> Oddly the worse I had was a old technology, ie single speed ie BMX
> freewheels will freeze up, and stop engaging. On a cold winters day in
> london ie no so cold there isn’t some unfrozen water, it will get into the
> hub freeze and stop it from engaging correctly…
>
>
>>
>>>
>>> My old commute beastie due to the miles it does plus the terrain, need all
>>> manner of things replaced, it’s a bit sluggish engaging at moment so will
>>> get shop to look at it as and when it next needs their talents!
>>>
>>> Roger Merriman
>>
>
> Roger Merriman
>

Freewheels need lubrication and I've also noticed the single
speed models pick up water more than multiple freewheels.
Oil it occasionally.

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

On Thu, 13 Jan 2022 12:26:49 -0600, AMuzi <am@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 Liebermann jeffl@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On Thu, 13 Jan 2022 13:56:27 -0800 (PST), "funkma...@hotmail.com"
<funkmasterxx@hotmail.com> wrote:

>... and the Metric Torx set.

<https://groups.google.com/g/rec.bicycles.tech/c/QfeGrZdzaUQ/m/9kIZCmMyAgAJ>

More than you probably wanted to know about Torx:
"Torx Bits vs Star Bits - What Are The Differences and Which Is
Better?"
<https://vehiclefreak.com/torx-bits-vs-star-bits-what-are-the-differences-and-which-is-better/>
...while the International Organization for Standardization
(ISO) has described the shape as hexalobular internal.
Next time you go to the hardware store, ask for a hexalobular driver
bit set.

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

On Thursday, January 13, 2022 at 7:06:55 PM UTC-5, Roger Merriman wrote:
> funkma...@hotmail.com <funkma...@hotmail.com> wrote:
> > On Thursday, January 13, 2022 at 3:43:30 PM UTC-5, 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!
> >
> > I was assuming he was referring to the Law of Diminishing Returns - which
> > I can concede would seemingly apply to _any_ hub in that price range.
> > However, There are many more expensive hubs out there, so generally
> > speaking I wouldn't personally say that this product is noteworthy in that context.
> >
> >>
> >> I’d also say that I generally like bike parts to be repairable by a bike
> >> shop.
> >
> > OH, c'mon roger, what fun is there in that? Don't you enjoy having to
> > scour the shop floor looking for that one loose ball bearing or that
> > lousy stinking derailleur stop screw you managed to drop? I've even had
> > to break out the magnet bar for a pawl spring that lept out of the
> > freehub assembly I was rebuilding and ended up ten feet away.
> >
> > Seriously though, this design is actually more simple since there are
> > _no_ springs (I did find a broken pawl spring once or twice). So unless
> > the magnet somehow dislodges, it would seem the failure rate of this
> > design is at least theoretically lower than a standard sprung pawl design.
> I’m not aware of the springs wearing or snapping

They do, I've seen it at least twice - once in a really expensive White Industries rear hub with a Ti axle.

> but well the fact that the
> hub will get water and mud ingress, and thus they do wear and need fixing
> even on the commute I occasionally take the woods home which can be soggy
> so all of the drive chain needs to be something that either I or bike shop
> can fix and get parts for.
>
> Which this technology doesn’t sound like it’s a good fit for, on a nice
> road bike that only comes out on the club run? Sure.
>
> Some technology doesn’t do well with over wet or gritty conditions.
>
> Oddly the worse I had was a old technology, ie single speed ie BMX
> freewheels will freeze up, and stop engaging. On a cold winters day in
> london ie no so cold there isn’t some unfrozen water, it will get into the
> hub freeze and stop it from engaging correctly…

Could simply be old grease that congealed in the colder weather, I've seen that before too.

> >
> >>
> >> My old commute beastie due to the miles it does plus the terrain, need all
> >> manner of things replaced, it’s a bit sluggish engaging at moment so will
> >> get shop to look at it as and when it next needs their talents!
> >>
> >> Roger Merriman
> >
> Roger Merriman

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)

>
> 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).

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/

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 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.

> 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.

AMuzi <am@yellowjersey.org> wrote:
> On 1/13/2022 6:06 PM, Roger Merriman wrote:
>> funkma...@hotmail.com <funkmasterxx@hotmail.com> wrote:
>>> On Thursday, January 13, 2022 at 3:43:30 PM UTC-5, 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!
>>>
>>> I was assuming he was referring to the Law of Diminishing Returns - which
>>> I can concede would seemingly apply to _any_ hub in that price range.
>>> However, There are many more expensive hubs out there, so generally
>>> speaking I wouldn't personally say that this product is noteworthy in that context.
>>>
>>>>
>>>> I’d also say that I generally like bike parts to be repairable by a bike
>>>> shop.
>>>
>>> OH, c'mon roger, what fun is there in that? Don't you enjoy having to
>>> scour the shop floor looking for that one loose ball bearing or that
>>> lousy stinking derailleur stop screw you managed to drop? I've even had
>>> to break out the magnet bar for a pawl spring that lept out of the
>>> freehub assembly I was rebuilding and ended up ten feet away.
>>>
>>> Seriously though, this design is actually more simple since there are
>>> _no_ springs (I did find a broken pawl spring once or twice). So unless
>>> the magnet somehow dislodges, it would seem the failure rate of this
>>> design is at least theoretically lower than a standard sprung pawl design.
>>
>> I’m not aware of the springs wearing or snapping but well the fact that the
>> hub will get water and mud ingress, and thus they do wear and need fixing
>> even on the commute I occasionally take the woods home which can be soggy
>> so all of the drive chain needs to be something that either I or bike shop
>> can fix and get parts for.
>>
>> Which this technology doesn’t sound like it’s a good fit for, on a nice
>> road bike that only comes out on the club run? Sure.
>>
>> Some technology doesn’t do well with over wet or gritty conditions.
>>
>> Oddly the worse I had was a old technology, ie single speed ie BMX
>> freewheels will freeze up, and stop engaging. On a cold winters day in
>> london ie no so cold there isn’t some unfrozen water, it will get into the
>> hub freeze and stop it from engaging correctly…
>>
>>
>>>
>>>>
>>>> My old commute beastie due to the miles it does plus the terrain, need all
>>>> manner of things replaced, it’s a bit sluggish engaging at moment so will
>>>> get shop to look at it as and when it next needs their talents!
>>>>
>>>> Roger Merriman
>>>
>>
>> Roger Merriman
>>
>
> Freewheels need lubrication and I've also noticed the single
> speed models pick up water more than multiple freewheels.
> Oil it occasionally.
>
Oh it’s long gone the SS bike that is about 8 years ago! Even so was
clearly freezing, than lubricant as such, de-icer would clear it!

Roger Merriman

On Friday, January 14, 2022 at 11:50:32 AM UTC+1, funkma...@hotmail.com wrote:

> 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.

Those leaf springs are often used in current hubs. I had/have them in my Hope hub, Zipp hubs and Tune hub. These are wear items and I don't really like them. Broke several of them. It will not end your ride but it is annoying.. What will end your ride is braking the spring in Campagnolo hub. This happened to me half the Passo Umbrail: https://en.wikipedia.org/wiki/Umbrail_Pass in the pooring rain on my way to Bormio. Luckily I got a ride from a nice Dutch couple with a free space on their bike rack. I was incredible lucky. I doubt that Campagnolo did a FMEA analyses. This poor design would not pass in my job. Since then I take my wheel with a DT240S hub when I go to the mountains.

Lou

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.

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?