Swapping internals in S-A hub?

[dabac]

Hi guys,

Are S-A hub shells identical across the range?

Aided by this forum I've been toying with various ideas on how to
improve the usefulness of a composite wheel with a 3-speed hub.
And although I now have a a fairly good idea on how to get a slightly
wider range and a few more intermediate gears by going to a triple front
with carefully calculated tooth counts I still haven't got the range
I'll need for a comfortable commute, using my current mtb-based ride as
a reference.

So, is there some other option I should consider before I try to graft
a Shimano-compatible DS hub flange onto the composite wheel by some
cruel and unusual method?

For instance, would it be possible to transplant the internals from a
S-A 5 speed into the hub shell of a 3-speed?


--
dabac

[James Thomson]

"A Muzi" <am@yellowjersey.org> a écrit:

> With Sturmey's S-5, gearing begins with AW's +33% high,
> direct, - 25% low then adds an additional +10% 'super high'
> and -10% 'super low'. Ten percent being a smallish difference,
> a rider who expects salvation with a 'bail out' gear when clicking
> from 2 to 1 may be disappointed.

It's a bit more than 10% (the middle three gears are spaced a touch narrower
than an AW). The two ratios are 15:19 (19:15) and 2:3 (3:2). That gives (as
a percentage of direct drive):

66.7 78.9 100 126.6 150

James Thomson

[jim beam]

jobst.brandt@stanfordalumni.org wrote:
> Frank Krygowski <frkrygow@gmail.com> wrote:
>
>>>> For instance, would it be possible to transplant the internals
>>>> from a S-A 5 speed into the hub shell of a 3-speed?
>
>>> Yes, at least with the older made-in-Britain ones. Mark Stonich in
>>> Minneapolis has done this mod several times. It's a straight swap.
>
>> I thought I read that the lowest gear of old S-A five speeds was
>> extremely inefficient. IOW, that shifting to low didn't really
>> reduce your workload significantly, but just gave you less speed.
>
>> I rode a friend's S-A five speed a few times, and got the impression
>> that the tale was true.
>
> So after riding up a few hundred yards of hill, was the hub noticeably
> warm? My son's SA S5 has ordinary planetary gears that have no more
> friction that other gears.

why don't you use hub gears?


> Low gear is achieved through the stepped
> planets that have a different number of teeth for input and output.
> That's all that's different.

and more idling componentry.

planetary gear trains have many advantages, but the same efficiency as
chain drive is not one of them. ever heard of frank berto?

[James Thomson]

"Frank Krygowski" <frkrygow@gmail.com> a écrit:

> Hmm. Not much meaningful discussion, though, from what I
> can see. Just two people disagreeing, with no relevant data.

Without wanting to appear conceited, there's a distinction to be made
between one participant who's familiar with only the myth, another who knows
the myth and uses the hubs in question, and others participants who aren't
familiar with the myth, the hubs, or the context.

Anyone who's familiar with these hubs knows that:

bottom gear is inefficient

and

bottom gear is not so inefficient as not to be useful.

The difficulty is trying to convey a sense of the problems with this
discussion to an audience that's broadly unfamiliar with hub gears in
general (hub gears never having had the popularity in North America that
they once had in Britain), and these hubs in particular.

Imagine if a rumour was in circulation that an S5 hub will play "God Save
the Queen" if shifted from middle to bottom gear without passing through
second. Someone familiar with the hubs might say it was nonsense - but
without proof, the rumour persists. Someone Googles and finds that some hubs
are said to emit noise in certain gears (a Rohloff plays "Im wunderschönen
Monat Mai" if shifted from eighth into seventh under load) so it's certainly
not impossible that a Sturmey plays "God Save the Queen" in certain gears.
Someone else says that he rode the hub in question fifteen years ago and
remembers distinctly that it made a noise, but it sounded more like "Rule
Britannia". Still, it was fifteen years ago. Someone postulates that a batch
of the hubs slipped through that played "Rule Britannia", which would
explain this exception to the well-known truth that all of these hubs play
"God Save the Queen".

For what it's worth, *everybody* knows that an S5/2 actually sings "Knees
Up, Mother Brown" to the tune of "Jerusalem". But only the batch with a blue
plastic oiler cap.

James Thomson

[Frank Krygowski]

On May 24, 6:47 pm, Tim McNamara <tim...@bitstream.net> wrote:
> In article
> <0ee921d9-7339-4279-b1af-dac25d4bc...@j22g2000hsf.googlegroups.com>,
> Frank Krygowski <frkry...@gmail.com> wrote:
>
>
>
> > On May 24, 1:59 am, "James Thomson" <yosnap...@hotmail.com> wrote:
> > > "Frank Krygowski" <frkry...@gmail.com> a écrit:
>
> > > > I thought I read that the lowest gear of old S-A five speeds was
> > > > extremely inefficient. IOW, that shifting to low didn't really
> > > > reduce your workload significantly, but just gave you less speed.
>
> > > That's an old myth. There's some relevant discussion in this
> > > thread:
>
> > >http://groups.google.fr/group/rec.bicycles.tech/browse_thread/thread
> > > /...
>
> > > James Thomson
>
> > Hmm. Not much meaningful discussion, though, from what I can see.
> > Just two people disagreeing, with no relevant data.
>
> > It would be nice to see some test data on the S-A 5 speed.
>
> In case your news server missed it, someone posted information they got
> from S-A about the efficiencies of the S-A 5 speed in the various gears.
> There was a pretty big drop in efficiency in gears 1 and 5. It should
> just a few posts back up the thread.

Ah, yes. That wasn't the news server (GG); that was my fault.
Thanks.

- Frank Krygowski

[Dan Burkhart]

James Thomson Wrote:
> "A Muzi" <am@yellowjersey.org> a écrit:
>
> > the S-5 was a minor rework of the long-produced and popular
> > FW gear train, so it wasn't, in a design sense, a totally new leap
> > for Sturmey Archer. Twenty years of FW by 1966.
> >
> > There's no difference in the low gear of an FW or an S-5, the
> > same parts being used in both.
>
> Thanks Andrew, I'm aware of that - I rode FWs for quite some time
> before my
> first five-speed, and still own a few, the oldest being a 1948. The
> interesting thing is that you never hear this myth in relation to the
> FW
> which, as you say, is mechanically identical except for the gear
> selector.
>
> > p.s. I'd take a trigger shifted FW, FG, FB 4 speed over an
> > S-5 with factory SA five speed controls any day.
>
> So would I, but I prefer a double-trigger S5/2.
>
> James Thomson
Sturmey Archer has recently come out with very nice "rapid fire" style
thumb shifters for 3 and 5 speed hubs. I have one of the 5 speed ones,
but I haven't tried it out yet.
Dan Burkhart
www.boomerbicycle.ca


--
Dan Burkhart

[A Muzi]

> Frank Krygowski <frkrygow@gmail.com> wrote:
>> I thought I read that the lowest gear of old S-A five speeds was
>> extremely inefficient. IOW, that shifting to low didn't really reduce
>> your workload significantly, but just gave you less speed.
>> I rode a friend's S-A five speed a few times, and got the impression
>> that the tale was true.

carlfogel@comcast.net wrote:
> Whatever the truth may be, this is a good example of the familiar RBT
> controversy:
>
> A poster heard about some effect, rode a bicycle, and things felt that
> way--so was the effect real, or was it just expectation?
>
> I couldn't find any efficiency testing of a 5-speed Sturmey-Archer,
> but even a detailed test might not have settled the question.
>
> After all, what if first gear was shown to be, say, 5.3% less
> efficient than second gear? Is that increased work-load actually
> noticeable while grinding up a hill at a 9.7% lower speed with [insert
> imaginary number here] less wind drag?
>
> The familiar Kyle & Berto efficiency study doesn't suggest that first
> gear in hub drives is a hidden boat anchor:
> http://www.ihpva.org/pubs/HP52.pdf
>
> Sometimes that pdf downloads, sometimes it doesn't. It's worth saving
> the damned file for later reference. Here's the table that compares
> the efficiency, gear-by-gear, of some hub-drives at 80, 150, and 200
> watts:
>
> 1 2 3 4 5 6 7 8 9 10 11 12 13 14
> Maker/Speeds
> Power Efficiency Percent**
> Sachs 3 80 95.0 92.9 93.6
> 150 94.2 95.6 94.8
> 200 94.1 94.9 94.1
> Shimano 3 80 90.5 93.5 87.2
> 150 93.0 93.9 88.6
> 200 93.2 95.0 87.2
> Sturmey 3 80 92.3 95.4 91.8
> 150 93.3 95.3 91.8
> 200 93.0 95.6 91.8
> Shimano 4 80 93.6 90.1 87.1 85.8
> Automatic 150 95.6 90.9 88.9 87.0
> 200 95.3 92.8 90.0 88.0
> Sachs 7 80 88.7 — — 89.2
> 150 89.9 — — 92.3
> 200* 91.0* — — 93.0*
> Shimano 7 80 90.8 90.7 87.4 89.0 83.6 90.9 88.2
> 150 91.8 92.9 89.9 89.0 85.6 92.8 90.4
> 200 92.8 94.5 90.3 91.8 86.4 93.7 91.4
> Sturmey 7 80 87.3 88.7 88.4 93.0 89.3 86.0 83.0
> 150 89.1 89.0 91.1 93.3 90.4 88.5 85.4
> 200 89.7 90.3 91.3 94.7 91.0 88.6 85.3
> Rohloff 14 80 89.1 90.3 87.8 90.3 87.5 87.8 86.1 89.7 90.8 87.7 89.7
> 87.1 87.8 86.1
> 150 90.6 92.5 89.9 92.2 89.6 91.0 89.9 92.6 92.7 90.4 92.3
> 90.4 89.7 89.1
> 200 91.3 92.5 90.9 93.4 90.5 90.9 90.2 92.8 92.7 91.1 93.5
> 90.0 91.1 90.4
>
> *The shift mechanism was broken, and would shift to only two gears.
>
> ** All efficiencies are uncorrected for the power consumed by the
> ergometer wheel drive. Although this is not large, it would increase
> the indicated efficiencies by 2 to 2.5% in most cases.
>
> ------------
>
> Here's how 1st gear efficiency compares to 2nd gear from that table:
>
> Sachs 3 +2.1% to -1.4%
> Shimano 3 -0.3% to -0.9%
> Shim auto 4 -2.5% to -5.7%
> Sachs 7 (broken, no data)
> Shimano 7 +0.1% to -1.7%
> Sturmey 7 +0.1% to -1.4%
> Rohloff 14 -1.2% to -1.9%
>
> So a typical hub-drive first gear loses less than 2% of power compared
> to second gear. That's less than the drag from a light generator.
>
> Some riders might claim that they can detect such <2% losses (<4 watts
> at 200 watts) even when they shift from one gear to another, but such
> sensitivity would be impressive.
>
> But Kyle & Berto didn't test the 5-speed Sturmey-Archer. Maybe that
> hub has some design quirk that makes its first gear a real dog, unlike
> the 3, 4, 7, and 14 speed hubs.

Efficiency, or lack thereof, is not at all obvious riding, at least to me.
(I switch semi-annually between an AW and a fixed gear. Same rims/tires.
Neither feels any more or less efficient. But then to Carl's comment,
my fixie has a tire driven dynamo. The other has a GH6 DynoHub.)

With Sturmey's S-5, gearing begins with AW's +33% high, direct, - 25%
low then adds an additional +10% 'super high' and -10% 'super low'. Ten
percent being a smallish difference, a rider who expects salvation with
a 'bail out' gear when clicking from 2 to 1 may be disappointed. And as
we know disappointment can lead to misdirected blame, "it's not efficient!".

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

[jim beam]

carlfogel@comcast.net wrote:
> On Thu, 22 May 2008 20:03:35 -0700 (PDT), Frank Krygowski
> <frkrygow@gmail.com> wrote:
>
>> I thought I read that the lowest gear of old S-A five speeds was
>> extremely inefficient. IOW, that shifting to low didn't really reduce
>> your workload significantly, but just gave you less speed.
>>
>> I rode a friend's S-A five speed a few times, and got the impression
>> that the tale was true.
>>
>> - Frank Krygowski
>
> Dear Frank,
>
> Whatever the truth may be, this is a good example of the familiar RBT
> controversy:
>
> A poster heard about some effect, rode a bicycle, and things felt that
> way--so was the effect real, or was it just expectation?

nah, i noticed this stuff when i was a kid too small to sit the seat of
my mother's s.a. 3-speed bike. my derailleured dad's bike, i could ride
with one leg through the frame so i had comparison. nobody then was
telling me about planetary gear boxes. certainly not my mother.



>
> I couldn't find any efficiency testing of a 5-speed Sturmey-Archer,
> but even a detailed test might not have settled the question.
>
> After all, what if first gear was shown to be, say, 5.3% less
> efficient than second gear? Is that increased work-load actually
> noticeable while grinding up a hill at a 9.7% lower speed with [insert
> imaginary number here] less wind drag?
>
> The familiar Kyle & Berto efficiency study doesn't suggest that first
> gear in hub drives is a hidden boat anchor:
> http://www.ihpva.org/pubs/HP52.pdf
>
> Sometimes that pdf downloads, sometimes it doesn't. It's worth saving
> the damned file for later reference. Here's the table that compares
> the efficiency, gear-by-gear, of some hub-drives at 80, 150, and 200
> watts:
>
> 1 2 3 4 5 6 7 8 9 10 11 12 13 14
> Maker/Speeds
> Power Efficiency Percent**
> Sachs 3 80 95.0 92.9 93.6
> 150 94.2 95.6 94.8
> 200 94.1 94.9 94.1
> Shimano 3 80 90.5 93.5 87.2
> 150 93.0 93.9 88.6
> 200 93.2 95.0 87.2
> Sturmey 3 80 92.3 95.4 91.8
> 150 93.3 95.3 91.8
> 200 93.0 95.6 91.8
> Shimano 4 80 93.6 90.1 87.1 85.8
> Automatic 150 95.6 90.9 88.9 87.0
> 200 95.3 92.8 90.0 88.0
> Sachs 7 80 88.7 � � 89.2
> 150 89.9 � � 92.3
> 200* 91.0* � � 93.0*
> Shimano 7 80 90.8 90.7 87.4 89.0 83.6 90.9 88.2
> 150 91.8 92.9 89.9 89.0 85.6 92.8 90.4
> 200 92.8 94.5 90.3 91.8 86.4 93.7 91.4
> Sturmey 7 80 87.3 88.7 88.4 93.0 89.3 86.0 83.0
> 150 89.1 89.0 91.1 93.3 90.4 88.5 85.4
> 200 89.7 90.3 91.3 94.7 91.0 88.6 85.3
> Rohloff 14 80 89.1 90.3 87.8 90.3 87.5 87.8 86.1 89.7 90.8 87.7 89.7
> 87.1 87.8 86.1
> 150 90.6 92.5 89.9 92.2 89.6 91.0 89.9 92.6 92.7 90.4 92.3
> 90.4 89.7 89.1
> 200 91.3 92.5 90.9 93.4 90.5 90.9 90.2 92.8 92.7 91.1 93.5
> 90.0 91.1 90.4
>
> *The shift mechanism was broken, and would shift to only two gears.
>
> ** All efficiencies are uncorrected for the power consumed by the
> ergometer wheel drive. Although this is not large, it would increase
> the indicated efficiencies by 2 to 2.5% in most cases.
>
> ------------
>
> Here's how 1st gear efficiency compares to 2nd gear from that table:
>
> Sachs 3 +2.1% to -1.4%
> Shimano 3 -0.3% to -0.9%
> Shim auto 4 -2.5% to -5.7%
> Sachs 7 (broken, no data)
> Shimano 7 +0.1% to -1.7%
> Sturmey 7 +0.1% to -1.4%
> Rohloff 14 -1.2% to -1.9%
>
> So a typical hub-drive first gear loses less than 2% of power compared
> to second gear. That's less than the drag from a light generator.

it's not about gear to gear, it's about overall efficiencies in the
80's. that's not good. and below 200W, hub hears really do show
noticeably lower power than chain gears.


>
> Some riders might claim that they can detect such <2% losses (<4 watts
> at 200 watts) even when they shift from one gear to another, but such
> sensitivity would be impressive.

what's even more "impressive" is people standing in line to claim they
/can't/ tell when they haven't even done any physical comparison! could
they paradoxically be the same people claiming detectable difference in
tire rolling resistance?


>
> But Kyle & Berto didn't test the 5-speed Sturmey-Archer. Maybe that
> hub has some design quirk that makes its first gear a real dog, unlike
> the 3, 4, 7, and 14 speed hubs.
>
> Cheers,
>
> Carl Fogel

[Jenny Brien]

On Thu, 22 May 2008 12:34:12 +0100, dabac
<dabac.39t81b@no-mx.forums.cyclingforums.com> wrote:

>
> Hi guys,
>
> Are S-A hub shells identical across the range?
>
> Aided by this forum I've been toying with various ideas on how to
> improve the usefulness of a composite wheel with a 3-speed hub.
> And although I now have a a fairly good idea on how to get a slightly
> wider range and a few more intermediate gears by going to a triple front
> with carefully calculated tooth counts I still haven't got the range
> I'll need for a comfortable commute, using my current mtb-based ride as
> a reference.
>
> So, is there some other option I should consider before I try to graft
> a Shimano-compatible DS hub flange onto the composite wheel by some
> cruel and unusual method?
>
> For instance, would it be possible to transplant the internals from a
> S-A 5 speed into the hub shell of a 3-speed?
>
>
Yes, I've done it

[jobst.brandt@stanfordalumni.org]

someone wrote:

> Aided by this forum I've been toying with various ideas on how to
> improve the usefulness of a composite wheel with a 3-speed hub. And
> although I now have a a fairly good idea on how to get a slightly
> wider range and a few more intermediate gears by going to a triple
> front with carefully calculated tooth counts I still haven't got the
> range I'll need for a comfortable commute, using my current
> MTB-based ride as a reference.

> So, is there some other option I should consider before I try to
> graft a Shimano-compatible DS hub flange onto the composite wheel by
> some cruel and unusual method?

> For instance, would it be possible to transplant the internals from
> a S-A 5 speed into the hub shell of a 3-speed?

They are identical and the 5-speed is less likely to pop into neutral
when sprinting.

Jobst Brandt

[Tim McNamara]

In article <dabac.39t81b@no-mx.forums.cyclingforums.com>,
dabac <dabac.39t81b@no-mx.forums.cyclingforums.com> wrote:

> Hi guys,
>
> Are S-A hub shells identical across the range?
>
> Aided by this forum I've been toying with various ideas on how to
> improve the usefulness of a composite wheel with a 3-speed hub. And
> although I now have a a fairly good idea on how to get a slightly
> wider range and a few more intermediate gears by going to a triple
> front with carefully calculated tooth counts I still haven't got the
> range I'll need for a comfortable commute, using my current mtb-based
> ride as a reference.
>
> So, is there some other option I should consider before I try to
> graft a Shimano-compatible DS hub flange onto the composite wheel by
> some cruel and unusual method?
>
> For instance, would it be possible to transplant the internals from a
> S-A 5 speed into the hub shell of a 3-speed?

Yes, at least with the older made-in-Britain ones. Mark Stonich in
Minneapolis has done this mod several times. It's a straight swap.

[dabac]

Jenny Brien Wrote:
> On Thu, 22 May 2008 12:34:12 +0100, dabac
> <dabac.39t81b@no-mx.forums.cyclingforums.com> wrote:
>
> >
> > Hi guys,
> >
> > Are S-A hub shells identical across the range?
> >
> > For instance, would it be possible to transplant the internals from
> a
> > S-A 5 speed into the hub shell of a 3-speed?
> >
> >
> Yes, I've done it

Good news! Now let's see what ebay has to offer...


--
dabac

[Frank Krygowski]

On May 22, 6:58 pm, Tim McNamara <tim...@bitstream.net> wrote:
> In article <dabac.39t...@no-mx.forums.cyclingforums.com>,
>
> > For instance, would it be possible to transplant the internals from a
> > S-A 5 speed into the hub shell of a 3-speed?
>
> Yes, at least with the older made-in-Britain ones. Mark Stonich in
> Minneapolis has done this mod several times. It's a straight swap.

I thought I read that the lowest gear of old S-A five speeds was
extremely inefficient. IOW, that shifting to low didn't really reduce
your workload significantly, but just gave you less speed.

I rode a friend's S-A five speed a few times, and got the impression
that the tale was true.

- Frank Krygowski

[James Thomson]

"Frank Krygowski" <frkrygow@gmail.com> a écrit:

> I thought I read that the lowest gear of old S-A five speeds
> was extremely inefficient. IOW, that shifting to low didn't
> really reduce your workload significantly, but just gave you
> less speed.

That's an old myth. There's some relevant discussion in this thread:

http://groups.google.fr/group/rec.bicycles.tech/browse_thread/thread/38ba32282ea4ff3d/

James Thomson

[carlfogel@comcast.net]

On Fri, 23 May 2008 12:35:36 -0700, jim beam
<spamvortex@bad.example.net> wrote:

[snip]

>it's not about gear to gear, it's about overall efficiencies in the
>80's.

[snip]

Dear Jim,

Frank wrote about how dropping from second to first in a 5-speed
Sturmey-Archer seemed to reveal a dramatic difference in efficiency.

He might be right, he might have been expecting the difference after
hearing about it somewhere, or he might have been expecting a bigger
jump than the 10% change, as Andrew Muzi points out elsewhere in this
thread.

In any case, this sub-thread is specifically about gear-to-gear
efficiency differences in the same hub.

Cheers,

Carl Fogel

[Frank Krygowski]

On May 23, 4:34 pm, carlfo...@comcast.net wrote:
>
>
> Frank wrote about how dropping from second to first in a 5-speed
> Sturmey-Archer seemed to reveal a dramatic difference in efficiency.

Well, what I really felt was "Wow. That downshift didn't seem to help
much at all. I'm working just as hard even though I'm climbing
slower."

The situation: Bike was an ancient ladies frame Dunelt, owned by a
widow friend. It had been her husbands. (He'd had a much larger rear
cog brazed onto the original.)

We were visiting on vacation, and I was attempting to give the bike a
little tuneup for her. Their town, in the Appalachian foothills,
featured lots of short steep climbs (hence the big rear cog). She'd
warned me that her husband had some trouble keeping the hub gear
properly adjusted, and it demonstrated some trouble with a false
neutral. I fussed with cable adjustment and improved things, but
never got it to shift perfectly.

I've reassembled S-A three speeds, but never a five speed. I'm not
familiar enough with the guts to know if some bad component in there
could generate both shifting problems and extra inefficiency in low
gear.

This was long ago (probably 15 years), so my memory isn't to be
trusted; but IIRC, I read about the inefficient low _after_ my
experience with that bike, so it was a case of the reading confirming
my impression, not vice-versa.

- Frank Krygowski

[carlfogel@comcast.net]

On Fri, 23 May 2008 17:29:48 -0700 (PDT), Frank Krygowski
<frkrygow@gmail.com> wrote:

>On May 23, 4:34 pm, carlfo...@comcast.net wrote:
>>
>>
>> Frank wrote about how dropping from second to first in a 5-speed
>> Sturmey-Archer seemed to reveal a dramatic difference in efficiency.
>
>Well, what I really felt was "Wow. That downshift didn't seem to help
>much at all. I'm working just as hard even though I'm climbing
>slower."
>
>The situation: Bike was an ancient ladies frame Dunelt, owned by a
>widow friend. It had been her husbands. (He'd had a much larger rear
>cog brazed onto the original.)
>
>We were visiting on vacation, and I was attempting to give the bike a
>little tuneup for her. Their town, in the Appalachian foothills,
>featured lots of short steep climbs (hence the big rear cog). She'd
>warned me that her husband had some trouble keeping the hub gear
>properly adjusted, and it demonstrated some trouble with a false
>neutral. I fussed with cable adjustment and improved things, but
>never got it to shift perfectly.
>
>I've reassembled S-A three speeds, but never a five speed. I'm not
>familiar enough with the guts to know if some bad component in there
>could generate both shifting problems and extra inefficiency in low
>gear.
>
>This was long ago (probably 15 years), so my memory isn't to be
>trusted; but IIRC, I read about the inefficient low _after_ my
>experience with that bike, so it was a case of the reading confirming
>my impression, not vice-versa.
>
>- Frank Krygowski

Dear Frank,

I kept looking and found these extended comments, which support and
explain your impression of 1st gear in a 5-speed Sturmey-Archer being
less efficient than 2nd gear. The actual claim from S-A is a drop from
93% to 89%, but that might mean as much as 93.4% to 88.5%.

Just to confuse things, there were two versions of the 5-speed S-A
hub.

***

David Henshaw, Oct 98:

The 5-speed Sturmey is less efficient than the 3-speed in gears 1 and
5. Try riding up the same hill on a 3-speed in gear 1 and a 5-speed in
gear 1. The lower gearing on the 5 gives no real advantage. I was
sceptical until Andrew Ritchie, the man himself, demonstrated this.
Now I believe it. And the 5 is very adjustment-sensitive, unlike the
3, which lasts forever and ever.

On a 5-speed, I'd go for a 14-tooth sprocket, which gives about 8%
lower gearing. But, please remember to change the shim pack - the 14T
is thicker than the 13T... The 12% optional lower gearing is certainly
worth fitting on the 5-speed if you want really low gearing, but I'm
not sure about the 18% - a front changer is probably a more sensible
option.

I'm still happiest with a light, efficient 3-speed with standard
gearing. My clunky old bike still holds the unofficial Brompton speed
record, set at CycleFest 1996 by Richard Grigsby.

***

Willi Mindak, Nov 98:

I received an e- mail today from Marketing at SA. This was in reply to
an e- mail I send over a month ago. It says:

Dear Sir

The only information I have on this type relates to the 5 speed hub,
the information is as follows:-

Efficiency

Gear Ratios Efficiency
Super Low 0.667 89%
Low 0.789 93%
Normal 1.00 96%
High 1.266 94%
Super High 1.5 88%

Efficiency Test Conditions

Motor Torque Arm balance weight = 2.2Kg
Motor Speed = 64 RPM
No. of chainwheel teeth = 46
No. of Sprocket teeth = 18

I hope this information assists you.
Yours faithfully
Trevor Wilkinson
Marketing Executive

No surprises here. Legend had it that 1st and 5th gear were a bit
harder to work. Third gear is best with no internal ratio; I take it
the 4% are just bearing/ chain losses. I also asked for the 3 speed
values, but no joy. Anyway, these values are in the expected range.
They are actually better than I thought.

***

Why is highest and lowest gear in a 5 speed less efficient than
highest and lowest in a 3 speed?

Stein Somers, Oct 1998:

My guess: in the extremer gears, the planets in the cage roll on a
bigger central fixed cog, hence they are smaller in diameter and make
more rounds per minute. Both factors increase the friction at their
(simple) bearings. Maybe on top more than three planets are needed to
cope with the driving forces because the teeth on a smaller planet
make less firm contact with the central cog.

Come to think of it, the basic planetary system can only reach a 2:1
drive ratio using infinitely small planets. That's a 400% gear ratio,
low to high gear. (SA-3 has 178%, SA-5 has 225%). So how does the
illustrious Rohloff hub obtain more than 500%??

Carsten Thies, Jan 2003:

It has two identical planetary gears in line, giving 7 gears*, plus an
additional step-down planetary gear for the lower 7 gears.
* it's not 3x3=9 gears because step-up step-down or vice versa would
give the same as direct gear.
Custfold, Oct 1998:

The reason for the extreme high/extreme low being accessed by pulling
the second lever should give a clue - the old SA5 system used a second
cable to pull the dog over on the LHS of the unit and engage a step-up
ratio in the drive chain - otherwise the middle 3 were direct into the
gear cage. This in turn means a bigger slot in the axle and extra
little piece to slide in it for all 5 speed hubs. The Sprinter merely
uses a longer pull stroke to operate a 2-stage little bit in a slot
from 1 cable.

***

Everything above is from:
http://stein.dommel.be/brompton/chapters/Gears.html#HubGearEfficiency

Cheers,

Carl Fogel

[A Muzi]

>> carlfo...@comcast.net wrote:
>>> Frank wrote about how dropping from second to first in a 5-speed
>>> Sturmey-Archer seemed to reveal a dramatic difference in efficiency.

> Frank Krygowski <frkrygow@gmail.com> wrote:
>> Well, what I really felt was "Wow. That downshift didn't seem to help
>> much at all. I'm working just as hard even though I'm climbing
>> slower."
>>
>> The situation: Bike was an ancient ladies frame Dunelt, owned by a
>> widow friend. It had been her husbands. (He'd had a much larger rear
>> cog brazed onto the original.)
>>
>> We were visiting on vacation, and I was attempting to give the bike a
>> little tuneup for her. Their town, in the Appalachian foothills,
>> featured lots of short steep climbs (hence the big rear cog). She'd
>> warned me that her husband had some trouble keeping the hub gear
>> properly adjusted, and it demonstrated some trouble with a false
>> neutral. I fussed with cable adjustment and improved things, but
>> never got it to shift perfectly.
>>
>> I've reassembled S-A three speeds, but never a five speed. I'm not
>> familiar enough with the guts to know if some bad component in there
>> could generate both shifting problems and extra inefficiency in low
>> gear.
>>
>> This was long ago (probably 15 years), so my memory isn't to be
>> trusted; but IIRC, I read about the inefficient low _after_ my
>> experience with that bike, so it was a case of the reading confirming
>> my impression, not vice-versa.

carlfogel@comcast.net wrote:
> I kept looking and found these extended comments, which support and
> explain your impression of 1st gear in a 5-speed Sturmey-Archer being
> less efficient than 2nd gear. The actual claim from S-A is a drop from
> 93% to 89%, but that might mean as much as 93.4% to 88.5%.
>
> Just to confuse things, there were two versions of the 5-speed S-A
> hub.
>
> ***
>
> David Henshaw, Oct 98:
>
> The 5-speed Sturmey is less efficient than the 3-speed in gears 1 and
> 5. Try riding up the same hill on a 3-speed in gear 1 and a 5-speed in
> gear 1. The lower gearing on the 5 gives no real advantage. I was
> sceptical until Andrew Ritchie, the man himself, demonstrated this.
> Now I believe it. And the 5 is very adjustment-sensitive, unlike the
> 3, which lasts forever and ever.
>
> On a 5-speed, I'd go for a 14-tooth sprocket, which gives about 8%
> lower gearing. But, please remember to change the shim pack - the 14T
> is thicker than the 13T... The 12% optional lower gearing is certainly
> worth fitting on the 5-speed if you want really low gearing, but I'm
> not sure about the 18% - a front changer is probably a more sensible
> option.
>
> I'm still happiest with a light, efficient 3-speed with standard
> gearing. My clunky old bike still holds the unofficial Brompton speed
> record, set at CycleFest 1996 by Richard Grigsby.
>
> ***
>
> Willi Mindak, Nov 98:
>
> I received an e- mail today from Marketing at SA. This was in reply to
> an e- mail I send over a month ago. It says:
>
> Dear Sir
>
> The only information I have on this type relates to the 5 speed hub,
> the information is as follows:-
>
> Efficiency
>
> Gear Ratios Efficiency
> Super Low 0.667 89%
> Low 0.789 93%
> Normal 1.00 96%
> High 1.266 94%
> Super High 1.5 88%
>
> Efficiency Test Conditions
>
> Motor Torque Arm balance weight = 2.2Kg
> Motor Speed = 64 RPM
> No. of chainwheel teeth = 46
> No. of Sprocket teeth = 18
>
> I hope this information assists you.
> Yours faithfully
> Trevor Wilkinson
> Marketing Executive
>
> No surprises here. Legend had it that 1st and 5th gear were a bit
> harder to work. Third gear is best with no internal ratio; I take it
> the 4% are just bearing/ chain losses. I also asked for the 3 speed
> values, but no joy. Anyway, these values are in the expected range.
> They are actually better than I thought.
>
> ***
>
> Why is highest and lowest gear in a 5 speed less efficient than
> highest and lowest in a 3 speed?
>
> Stein Somers, Oct 1998:
>
> My guess: in the extremer gears, the planets in the cage roll on a
> bigger central fixed cog, hence they are smaller in diameter and make
> more rounds per minute. Both factors increase the friction at their
> (simple) bearings. Maybe on top more than three planets are needed to
> cope with the driving forces because the teeth on a smaller planet
> make less firm contact with the central cog.
>
> Come to think of it, the basic planetary system can only reach a 2:1
> drive ratio using infinitely small planets. That's a 400% gear ratio,
> low to high gear. (SA-3 has 178%, SA-5 has 225%). So how does the
> illustrious Rohloff hub obtain more than 500%??
>
> Carsten Thies, Jan 2003:
>
> It has two identical planetary gears in line, giving 7 gears*, plus an
> additional step-down planetary gear for the lower 7 gears.
> * it's not 3x3=9 gears because step-up step-down or vice versa would
> give the same as direct gear.
> Custfold, Oct 1998:
>
> The reason for the extreme high/extreme low being accessed by pulling
> the second lever should give a clue - the old SA5 system used a second
> cable to pull the dog over on the LHS of the unit and engage a step-up
> ratio in the drive chain - otherwise the middle 3 were direct into the
> gear cage. This in turn means a bigger slot in the axle and extra
> little piece to slide in it for all 5 speed hubs. The Sprinter merely
> uses a longer pull stroke to operate a 2-stage little bit in a slot
> from 1 cable.
>
> ***
>
> Everything above is from:
> http://stein.dommel.be/brompton/chapters/Gears.html#HubGearEfficiency

From Somers above "Maybe on top more than three planets are needed "

S5 and AW each have four planet gears (Brit: pinions), not three.

p.s. SW have three, but SW of course 'Seldom Work';AWs 'Always Work'!

p.p.s Yes I know it's 'Type A, Wide Range' but the mnemonic is cute.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

[Tim McNamara]

In article <d08bd$483785dd$30748@news.teranews.com>,
A Muzi <am@yellowjersey.org> wrote:

> From Somers above "Maybe on top more than three planets are needed "
>
> S5 and AW each have four planet gears (Brit: pinions), not three.

My Sachs Torpedo 3 speed hub has, as far as I have found out from
searching on the net, 3 planet gears and that hub has a reputation for
reliability that is better than the AW (no walking out of engagement in
high gear). It also rated a bit higher in efficiency in Frank Berto's
tests- perhaps due to having three rather than four planet gears?

> p.s. SW have three, but SW of course 'Seldom Work';AWs 'Always Work'!
>
> p.p.s Yes I know it's 'Type A, Wide Range' but the mnemonic is cute.

Well, perhaps "'Twill Always Work Right" would fit. :-)

[Tim McNamara]

In article <48392e91$0$901$ba4acef3@news.orange.fr>,
"James Thomson" <yosnappyj@hotmail.com> wrote:

> "Frank Krygowski" <frkrygow@gmail.com> a écrit:
>
> > Hmm. Not much meaningful discussion, though, from what I can see.
> > Just two people disagreeing, with no relevant data.
>
> Without wanting to appear conceited, there's a distinction to be made
> between one participant who's familiar with only the myth, another
> who knows the myth and uses the hubs in question, and others
> participants who aren't familiar with the myth, the hubs, or the
> context.
>
> Anyone who's familiar with these hubs knows that:
>
> bottom gear is inefficient
>
> and
>
> bottom gear is not so inefficient as not to be useful.

S-A's own numbers, as published earlier in the thread, show a steep drop
in efficiency in gears 1 and 5. Let's not forget that we do have some
facts to go on in this discussion. We should also mention that while
hub gears fall below the vaunted "98% efficiency" claimed for derailleur
systems, that latter number is achieved with optimum conditions- clean
drivetrain, centered chainline, fairly large cogs, etc. As cogs get
smaller, efficiency drops significantly (according to Berto's published
measurements in _The Dancing Chain_) and can easily be no better than a
hub geared system.

> The difficulty is trying to convey a sense of the problems with this
> discussion to an audience that's broadly unfamiliar with hub gears in
> general (hub gears never having had the popularity in North America
> that they once had in Britain), and these hubs in particular.

Hub gears were the dominant form of variable gearing in the US from WWII
until about the mid 1960s, when Schwinn began to have success in
marketing derailleur geared bikes. Youngsters under 30 might never have
ridden a bike with hub gears, but Frank and I and Jobst and a number of
other participants in this group are older than that. I still have a
bike with a three speed hub, which I ride frequently, and know a few
dozen people who ride bikes with hub gears frequently. They are not
really rara avis, after all, even if not so common. My friend Jim's
bike shop, which caters to bike commuters and the like rather than
racers, sells a fair number of modern new bikes (Breezer) with hub gears
annually.

The hub gear situation in Britain seems to be not radically different.
Derailleurs appear to have taken over there even earlier than in the US.

[Frank Krygowski]

On May 25, 5:14 am, "James Thomson" <yosnap...@hotmail.com> wrote:
> "Frank Krygowski" <frkry...@gmail.com> a écrit:
>
> > Hmm. Not much meaningful discussion, though, from what I
> > can see. Just two people disagreeing, with no relevant data.
>
> Without wanting to appear conceited, there's a distinction to be made
> between one participant who's familiar with only the myth, another who knows
> the myth and uses the hubs in question, and others participants who aren't
> familiar with the myth, the hubs, or the context.
>
> Anyone who's familiar with these hubs knows that:
>
> bottom gear is inefficient
>
> and
>
> bottom gear is not so inefficient as not to be useful.

James, pardon me, but you're really saying "I know I'm right and
others are wrong." Data trumps self confidence. I thank Carl for (as
usual) searching out actual data.

I'll also note, the only 5 speed S-A I've ever ridden (that old
Dunelt) did have shifting problems. I could give even more detail,
but suffice to say I was never satisfied with the reliability of its
shifting. So my impressions could be clouded by a bad sample.

- Frank Krygowski

[James Thomson]

>> Anyone who's familiar with these hubs knows that:
>>
>> bottom gear is inefficient
>>
>> and
>>
>> bottom gear is not so inefficient as not to be useful.

"Tim McNamara" <timmcn@bitstream.net> a écrit:

> S-A's own numbers, as published earlier in the thread,

Not in the thread I was referring to:

http://groups.google.fr/group/rec.bicycles.tech/browse_thread/thread/38ba32282ea4ff3d/

> show a steep drop in efficiency in gears 1 and 5.

Of course they do. Anyone who's familiar with these hubs knows that.

> Let's not forget that we do have some
> facts to go on in this discussion.

> We should also mention that while hub gears fall below the vaunted
> "98% efficiency" claimed for derailleur systems, that latter number is
> achieved with optimum conditions- clean drivetrain, centered chainline,
> fairly large cogs, etc. As cogs get smaller, efficiency drops
> significantly
> (according to Berto's published measurements in _The Dancing Chain_)
> and can easily be no better than a hub geared system.

*Why* should we mention that? What's the relevance to a discussion of the
relative efficiencies of two adjacent gears in a specific (Sturmey
five-speed) hub?

> Hub gears were the dominant form of variable gearing in the US
> from WWII until about the mid 1960s, when Schwinn began to have
> success in marketing derailleur geared bikes. Youngsters under
> 30 might never have ridden a bike with hub gears, but Frank and I
> and Jobst and a number of other participants in this group are older
> than that. I still have a bike with a three speed hub, which I ride
> frequently, and know a few dozen people who ride bikes with hub
> gears frequently.

Frank and Jobst didn't participate in the thread to which I was referring
(*that* thread, not *this* one). Your contribution was to draw a tentative
analogy between a three speed hub (with which you're familiar) and a seven
(with which you said you were - at least on that point - unfamiliar) in a
thread about a five (with which, presumably, you were unfamiliar). I think
that we might be using the same word ("familiarity") to mean rather
different things. The first Sturmey five-speeds appeared in 1966,
incidentally.

> The hub gear situation in Britain seems to be not radically different.
> Derailleurs appear to have taken over there even earlier than in the US.

I don't think that's true. Hub gears had quite a strong market in the UK -
at least amongst enthusiasts - through the eighties. They've now found their
way back to the mass market after a severe decline during the nineties, but
the target market now seems less likely to be inclined to care about what's
going on inside the can.

James Thomson

[James Thomson]

"Frank Krygowski" <frkrygow@gmail.com> a écrit:

> > > Hmm. Not much meaningful discussion, though, from what I
> > > can see. Just two people disagreeing, with no relevant data.

> James, pardon me, but you're really saying "I know I'm right
> and others are wrong." Data trumps self confidence.

Data's nice, but in the absence of relevant data (as in the previous
thread), experience and inexperience aren't equivalent. I stand by my point.

James Thomson

[A Muzi]

>>> Anyone who's familiar with these hubs knows that:
>>> bottom gear is inefficient
>>> and
>>> bottom gear is not so inefficient as not to be useful.

> "Tim McNamara" <timmcn@bitstream.net> a écrit:
>> S-A's own numbers, as published earlier in the thread,

James Thomson wrote:
> Not in the thread I was referring to:
> http://groups.google.fr/group/rec.bicycles.tech/browse_thread/thread/38ba32282ea4ff3d/

>> show a steep drop in efficiency in gears 1 and 5.

James Thomson wrote:
> Of course they do. Anyone who's familiar with these hubs knows that.

> "Tim McNamara" <timmcn@bitstream.net> a écrit:
>> Let's not forget that we do have some
>> facts to go on in this discussion.
>> We should also mention that while hub gears fall below the vaunted
>> "98% efficiency" claimed for derailleur systems, that latter number is
>> achieved with optimum conditions- clean drivetrain, centered chainline,
>> fairly large cogs, etc. As cogs get smaller, efficiency drops
>> significantly
>> (according to Berto's published measurements in _The Dancing Chain_)
>> and can easily be no better than a hub geared system.

James Thomson wrote:
> *Why* should we mention that? What's the relevance to a discussion of the
> relative efficiencies of two adjacent gears in a specific (Sturmey
> five-speed) hub?

> "Tim McNamara" <timmcn@bitstream.net> a écrit:
>> Hub gears were the dominant form of variable gearing in the US
>> from WWII until about the mid 1960s, when Schwinn began to have
>> success in marketing derailleur geared bikes. Youngsters under
>> 30 might never have ridden a bike with hub gears, but Frank and I
>> and Jobst and a number of other participants in this group are older
>> than that. I still have a bike with a three speed hub, which I ride
>> frequently, and know a few dozen people who ride bikes with hub
>> gears frequently.

James Thomson wrote:
> Frank and Jobst didn't participate in the thread to which I was referring
> (*that* thread, not *this* one). Your contribution was to draw a tentative
> analogy between a three speed hub (with which you're familiar) and a seven
> (with which you said you were - at least on that point - unfamiliar) in a
> thread about a five (with which, presumably, you were unfamiliar). I think
> that we might be using the same word ("familiarity") to mean rather
> different things. The first Sturmey five-speeds appeared in 1966,
> incidentally.

> "Tim McNamara" <timmcn@bitstream.net> a écrit:
>> The hub gear situation in Britain seems to be not radically different.
>> Derailleurs appear to have taken over there even earlier than in the US.

James Thomson wrote:
> I don't think that's true. Hub gears had quite a strong market in the UK -
> at least amongst enthusiasts - through the eighties. They've now found their
> way back to the mass market after a severe decline during the nineties, but
> the target market now seems less likely to be inclined to care about what's
> going on inside the can.

I'm not sure where "first appeared in 1966" fits in but the S-5 was a
minor rework of the long-produced and popular FW gear train, so it
wasn't, in a design sense, a totally new leap for Sturmey Archer. Twenty
years of FW by 1966.

There's no difference in the low gear of an FW or an S-5, the same parts
being used in both.

p.s. I'd take a trigger shifted FW, FG, FB 4 speed over an S-5 with
factory SA five speed controls any day. Changing an S-5 to double
trigger shifters makes them 'better' but still not quite as far as
'excellent'.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

[Tim McNamara]

In article <483c6654$0$874$ba4acef3@news.orange.fr>,
"James Thomson" <yosnappyj@hotmail.com> wrote:

> "Frank Krygowski" <frkrygow@gmail.com> a écrit:
>
> > > > Hmm. Not much meaningful discussion, though, from what I can
> > > > see. Just two people disagreeing, with no relevant data.
>
> > James, pardon me, but you're really saying "I know I'm right and
> > others are wrong." Data trumps self confidence.
>
> Data's nice, but in the absence of relevant data (as in the previous
> thread), experience and inexperience aren't equivalent. I stand by my
> point.

So, to sum up, you know what you know and don't want to be bothered with
facts. Okee-dokee, I won't bother you again.

[jobst.brandt@stanfordalumni.org]

Dan Burkhart wrote:

>>> the S-5 was a minor rework of the long-produced and popular FW
>>> gear train, so it wasn't, in a design sense, a totally new leap
>>> for Sturmey Archer. Twenty years of FW by 1966.

>>> There's no difference in the low gear of an FW or an S-5, the same
>>> parts being used in both.

>> Thanks Andrew, I'm aware of that - I rode FWs for quite some time
>> before my first five-speed, and still own a few, the oldest being a
>> 1948. The interesting thing is that you never hear this myth in
>> relation to the FW which, as you say, is mechanically identical
>> except for the gear selector.

>>> p.s. I'd take a trigger shifted FW, FG, FB 4 speed over an S-5
>>> with factory SA five speed controls any day.

>> So would I, but I prefer a double-trigger S5/2.

> Sturmey Archer has recently come out with very nice "rapid fire"
> style thumb shifters for 3 and 5 speed hubs. I have one of the 5
> speed ones, but I haven't tried it out yet.

Looking at the Sturmey Archer pages, I am disappointed to see they
never change, apparently because they believe they have the ultimate
hubs. The flanges are 2mm thick, a feature that in the aluminum hubs
causes large spoke hole deformation and on both steel and aluminum hub
(shells) causes spoke failure, the elbows of spokes being designed for
3mm flanges.

http://www.sturmey-archer.com/hubs_5spd_S5_A.php

My son's S5 hub has 3mm flanges because Tom Ritchey machined one from
aluminum bar stock for me. I am not amused. They never fixed the AW
3-speed hub to not pop out of top gear under continuous load.

Jobst Brandt

[James Thomson]

<jobst.brandt@stanfordalumni.org> a écrit:

> Looking at the Sturmey Archer pages, I am disappointed to see they
> never change, apparently because they believe they have the ultimate
> hubs. The flanges are 2mm thick, a feature that in the aluminum hubs
> causes large spoke hole deformation and on both steel and aluminum
> hub (shells) causes spoke failure, the elbows of spokes being designed
> for 3mm flanges.

I'm not sure where you found that information, but I have a modern
(Taiwanese production) X-RF5 aluminium shell here, and the flanges are 3mm
thick at the spoke holes. 1980s aluminium-shelled 3- and 5-speeds also have
3mm flanges. The 1940s and '50s alloy-shelled hubs did have thin, fragile
flanges.

James Thomson

[jobst.brandt@stanfordalumni.org]

James Thomson <yosnappyj@hotmail.com> wrote:

>> Looking at the Sturmey Archer pages, I am disappointed to see they
>> never change, apparently because they believe they have the ultimate
>> hubs. The flanges are 2mm thick, a feature that in the aluminum hubs
>> causes large spoke hole deformation and on both steel and aluminum
>> hub (shells) causes spoke failure, the elbows of spokes being designed
>> for 3mm flanges.

> I'm not sure where you found that information, but I have a modern
> (Taiwanese production) X-RF5 aluminium shell here, and the flanges
> are 3mm thick at the spoke holes. 1980s aluminium-shelled 3- and
> 5-speeds also have 3mm flanges. The 1940s and '50s alloy-shelled
> hubs did have thin, fragile flanges.

http://www.sturmey-archer.com/hubs_5spd_S5_A.php

I am sure. The picture is accurate and the S5 shell that I have
measures 2mm. Tom Ritchey did his lathe work to make 3mm flanges of
good strength aluminum and it worked. I was impressed by his ability
to cut double lead threads for the drive side. The S5 I have is from
the 1970's.

Jobst Brandt

[James Thomson]

<jobst.brandt@stanfordalumni.org> a écrit:

> http://www.sturmey-archer.com/hubs_5spd_S5_A.php

> I am sure. The picture is accurate and the S5 shell that I
> have measures 2mm.

The picture shows a steel-shelled hub.

> The S5 I have is from the 1970's.

and steel-shelled.

I don't dispute that Sturmey's steel-shelled hubs have thin flanges. Their
modern aluminium-shelled hubs, in common with those made in the 1980s, have
3mm flanges:

http://www.sturmey-archer.com/hubs_5spd_XRF5.php

In your previous post you made no distinction.

James Thomson

[Ryan Cousineau]

In article <4843967f$0$17145$742ec2ed@news.sonic.net>,
jobst.brandt@stanfordalumni.org wrote:

> James Thomson <yosnappyj@hotmail.com> wrote:
>
> >> Looking at the Sturmey Archer pages, I am disappointed to see they
> >> never change, apparently because they believe they have the ultimate
> >> hubs. The flanges are 2mm thick, a feature that in the aluminum hubs
> >> causes large spoke hole deformation and on both steel and aluminum
> >> hub (shells) causes spoke failure, the elbows of spokes being designed
> >> for 3mm flanges.
>
> > I'm not sure where you found that information, but I have a modern
> > (Taiwanese production) X-RF5 aluminium shell here, and the flanges
> > are 3mm thick at the spoke holes. 1980s aluminium-shelled 3- and
> > 5-speeds also have 3mm flanges. The 1940s and '50s alloy-shelled
> > hubs did have thin, fragile flanges.
>
> http://www.sturmey-archer.com/hubs_5spd_S5_A.php
>
> I am sure. The picture is accurate and the S5 shell that I have
> measures 2mm. Tom Ritchey did his lathe work to make 3mm flanges of
> good strength aluminum and it worked. I was impressed by his ability
> to cut double lead threads for the drive side. The S5 I have is from
> the 1970's.
>
> Jobst Brandt

Interesting. The S5 Jobst is linking to looks like a faithful
continuation of the classic S5 design. Conversely, James is referring to
the XRF5:

http://www.sturmey-archer.com/hubs_5spd_XRF5.php

Which is the "new" design which has probably been around quite some time
by now.

For all that, the old design does still appear to be available as a
stock item from some retailers:

<http://www.sjscycles.co.uk/src/froogleUS/currency/USD/product-Sturmey-Ar
cher-Sturmey-Archer-5-Speed-SPRINTER-S5-Steel-Shell-Rear-Hub-with-Gear-Co
ntrol-HSJ839-36-hole-8035.htm>

So Sturmey is both good and bad! Pick your poison.

--
Ryan Cousineau rcousine@gmail.com http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."

[Dan Burkhart]

jobst.brandt@stanfordalumni.org Wrote:
> James Thomson <yosnappyj@hotmail.com> wrote:
>
> >> Looking at the Sturmey Archer pages, I am disappointed to see they
> >> never change, apparently because they believe they have the
> ultimate
> >> hubs. The flanges are 2mm thick, a feature that in the aluminum
> hubs
> >> causes large spoke hole deformation and on both steel and aluminum
> >> hub (shells) causes spoke failure, the elbows of spokes being
> designed
> >> for 3mm flanges.
>
> > I'm not sure where you found that information, but I have a modern
> > (Taiwanese production) X-RF5 aluminium shell here, and the flanges
> > are 3mm thick at the spoke holes. 1980s aluminium-shelled 3- and
> > 5-speeds also have 3mm flanges. The 1940s and '50s alloy-shelled
> > hubs did have thin, fragile flanges.
>
> http://www.sturmey-archer.com/hubs_5spd_S5_A.php
>
> I am sure. The picture is accurate and the S5 shell that I have
> measures 2mm. Tom Ritchey did his lathe work to make 3mm flanges of
> good strength aluminum and it worked. I was impressed by his ability
> to cut double lead threads for the drive side. The S5 I have is from
> the 1970's.
>
> Jobst Brandt
Someone went to a lot of trouble for naught.
http://i30.tinypic.com/oa81tg.jpg

Sturmey Archer's web site apears to not have caught up with their new
product offerings. Here's some shots of the new 5 speed shifter. The 3
speed looks the same.
http://i32.tinypic.com/i6eg53.jpg
http://i32.tinypic.com/5oi7nb.jpg
http://i29.tinypic.com/29lcveu.jpg
They also have not updated the technical info on the new 8 speed
hub.The ratios have changed and the hub shell shape has changed.
Dan Burkhart
www.boomerbicycle.ca


--
Dan Burkhart

[James Thomson]

"Ryan Cousineau" <rcousine@gmail.com> a écrit:

> Interesting. The S5 Jobst is linking to looks like a faithful
> continuation of the classic S5 design.

There's a distinction to be made between the "classic" S5 of the sixties and
early seventies, and that modern hub, which is very similar to the Sprinter
5. The old S5 (referred to by Andrew above in the thread) used two control
cables, with a toggle chain on the right and a bell crank on the left:

http://www.sturmey-archerheritage.com/detail.php?id=104

The modern S5 and XRF5 are identical apart from the shell.

> For all that, the old design does still appear to be available
> as a stock item from some retailers:

One reason for that is that the big aluminium flanges of the XRF5 cause
clearance problems with the stays of some folding bikes.

James Thomson