Rohloff makes the case for Cyber Nexus

Andre Jute wrote:
Not that I'm more familiar with the Rohloff 500/14 hub gearbox and
settling in to a pattern of using it, in thing stands out: for
efficiency, you have to work it.

I tend to avoid the geers 7 and below, because they make a depressing
sighing sound. But even in the higher gears, I tend to stay in gear
and mash my way up the incline rather than bother with the stiff
gearchange.

That is not the most efficient way to ride. It might make me fitter
faster, but what we're discussing here is the bike's mechanical
efficiency, not my respiration rate.

Shimano's Cyber Nexus full-automatic hub gears on the other hand
changes gears smoothly to permit the cyclist the maximum speed his pre-
selected exertion level can provide. The rider exerts the same energy,
regardless of the road. In my case this level was set with a minimum
of experimentation and fuss at 80% of my maximum heart rate.

No human can change gears as efficiently as Shimano's Cyber Nexus.

I also have on another bike a manual version of the Nexus Premium/
Alfine gearbox the Cyber Nexus is built on, though I don't want to
pretend I changed gears on that much smoother box (than the Rohloff)
for maximum efficiency all the time. But a large proportion of the
time I did use it well.

The Rohloff with its even gearing steps but with its stiff change thus
makes a convincing case -- for an automatic gearbox!

I don't think it would be difficult to make an automatik Rohloff, and
there could be a small market for it.

Shimano's full-auto hub and derailleur gearboxes are still going but
the prognosis is not good because Shimano has a long history of
ruthlessly killing products which reach only niche markets. I fear
that the Cyber Nexus will become merely a footnote to the
electronically assisted (not automatic) Dura-Ace shifter derived from
it. (The Dura-Ace shifter is a joke, a sop to the macho attitudes of
the roadies, nothing to do with extracting the maximum efficiency from
gears and cyclist.)

However, Rohloff can work within much smaller, specialist markets. I
for one would happily pay two or three hundred Euro for a kit to add
electronic shifting (powered by the hub dynamo already on my bikes) to
the Rohloff box.

Long way to say "I'm too lazy to shift".

--
Tom Sherman - 42.435731,-83.985007
LOCAL CACTUS EATS CYCLIST - datakoll

Hi,

Andre Jute wrote:
Well, no, it's a pretty obvious conclusion. The human will always be
seconds slower on each gearchange than electronics can be.

You know, I can even shift beforehand - that is, when I approach a hill,
I can shift (manually) just before I hit the grade and be in the perfect
gear right away ;-)

That's even better than automatic shifting ;-)

Now that's a personality thing. He should have lent it to you for a
week so you could get used to it.

There's some truth in there - you do need to get used to it. You do need
to *want* to get used to it, actually ;-)

You know, I'm actually looking for a semi-automatic gear shift...
Because on my bike I have two points causing discomfort:

(1) the cables are unusually long, causing more wear on cables (I'm on
my second set in 10.000km and they're still fine ;-) Cable routing is
not nice, either, since I did want them fully-enclosed and routed along
the top tube...

(2) Sometimes I do have to shift both shifters for several gears at
once. This is especially tricky at night (when you don't see the gear
indicator).

So, I would gladly use an electronic (or hydraulic) semi-automatic
shifter, which would select the next appropriate gear on my pressing a
button (up/down). I would even distribute multiple buttons around my
handlebars...

Of course I would have to program the thing to select the gears in the
correct sequence which is quite a challenge (use Sheldon Brown's gear
calculator ;-) Or it would need quite a set of sensors to gather the
necessary data for calculating the sequence itself (and some
"self-setup" time on a workstand).

With the fully automatic mode it is a dangerous thing. Some users would
really need it, but would never pay for it (they won't even buy a new
bike when the old one is "still working" - but really a piece of junk).
The ones who would pay for it consider themselves so proficient they
wouldn't want to get caught with it. Others would find it annoying...
Actually I wouldn't mind my "semi-automatic" shifter to have an
automatic mode (which I can deactivate easily ;-)

Overall I do think there is a *lot* of potential for innovation in bike
technology, but it's a very difficult market...

Ciao..

"Andre Jute" wrote...

[...]
Of course it calculates effort, to compare it to the effort level
chosen as a target, but it measures effort indirectly.

In which way?

[...]
Andre Jute

Gennaro

On Apr 28, 2:59 pm, "Gennaro" wrote:
"Andre Jute" wrote...

[...]

Of course it calculates effort, to compare it to the effort level
chosen as a target, but it measures effort indirectly.

In which way?

There's a speed sensor in the dedicated hub dynamo of Shimano's Cyber
Nexus gruppo, and an inclination sensor somewhere. The central
processing unit of the electronic controller knows in which gear the
bike is and the ratio of that gear. Speed, inclination and gear
together give effort, indirectly as I said. The rider sets his desired
optimum effort on a dial, the electronics compare the current real
effort to the desired effort, and changes accordingly.

There is more detail in the description of my Trek "Smover" on my
netsite.

HTH.

Andre Jute
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

"Andre Jute" wrote in message
...
On Apr 28, 2:59 pm, "Gennaro" wrote:
"Andre Jute" wrote...

[...]

Of course it calculates effort, to compare it to the effort level
chosen as a target, but it measures effort indirectly.

In which way?

There's a speed sensor in the dedicated hub dynamo of Shimano's Cyber
Nexus gruppo, and an inclination sensor somewhere.

Is there really an inclination sensor in there? I'd be interested to see
mention of it on a Shimano manual/website.

On Apr 28, 2:29*pm, Bernhard Agthe wrote:
Hi,

Andre Jute wrote:
Well, no, it's a pretty obvious conclusion. The human will always be
seconds slower on each gearchange than electronics can be.

You know, I can even shift beforehand - that is, when I approach a hill,
I can shift (manually) just before I hit the grade and be in the perfect
gear right away ;-)

That's even better than automatic shifting ;-)

Sorry to disappoint you, Bernard, but if you change "beforehand" there
will be several meters where you and the bike do not operate at
maximum efficiency. No human an react as fast as electronics.

Whether it matters is a question of whether the extra weight overall
slows you down more than you gain with the perfectly optimum gear
changes. I wouldn't know; I ride a different style of bike and in a
different way (I control effort with a heart rate monitor, not by
speed or cadence).

Now that's a personality thing. He should have lent it to you for a
week so you could get used to it.

There's some truth in there - you do need to get used to it. You do need
to *want* to get used to it, actually ;-)

Gearheads unite!

You know, I'm actually looking for a semi-automatic gear shift...
Because on my bike I have two points causing discomfort:

(1) the cables are unusually long, causing more wear on cables (I'm on
my second set in 10.000km and they're still fine ;-) Cable routing is
not nice, either, since I did want them fully-enclosed and routed along
the top tube...

(2) Sometimes I do have to shift both shifters for several gears at
once. This is especially tricky at night (when you don't see the gear
indicator).

So, I would gladly use an electronic (or hydraulic) semi-automatic
shifter, which would select the next appropriate gear on my pressing a
button (up/down). I would even distribute multiple buttons around my
handlebars...

Of course I would have to program the thing to select the gears in the
correct sequence which is quite a challenge (use Sheldon Brown's gear
calculator ;-) Or it would need quite a set of sensors to gather the
necessary data for calculating the sequence itself (and some
"self-setup" time on a workstand).

With the fully automatic mode it is a dangerous thing. Some users would
really need it, but would never pay for it (they won't even buy a new
bike when the old one is "still working" - but really a piece of junk).
The ones who would pay for it consider themselves so proficient they
wouldn't want to get caught with it. Others would find it annoying...
Actually I wouldn't mind my "semi-automatic" shifter to have an
automatic mode (which I can deactivate easily ;-)

Overall I do think there is a *lot* of potential for innovation in bike
technology, but it's a very difficult market...

Ciao..

A long reply I wrote seems to have got lost in the ether, so apologies
if you're getting some of this twice:

Shimano's Cyber Nexus in its full flowering comes in two versions, one
for hub gears, one for derailleur gears. Both have fully auto and
electronically assisted manual modes. Neither gruppo was ever sold at
retail to the public as far as I know. Gazelle still sells a version
of the Saphir (whatever it is called now) with the Cyber Nexus hub
gearbox. Koga-Miyata used to sell the Excellence with the full Cyber
Nexus group including the electronic adaptive fork, as on my Trek
"Smover", more details on my netsite. Maybe Koga still has a
derailleur gruppo on the shelf they want to sell you; maybe the German
agent, Paul Lange, will supply you.

Shimano also makes a cut-down version of the Cyber Nexus for racers;
it is part of one of the Dura-Ace gruppo. It is battery-powered rather
than dynohub powered, and all it does is electronically assisted
shifting, no full-auto mode.

There are hints that you're thinking of a do it yourself electronic
system. The Shimano system is superbly efficient but depends on
proprietary parts, like a stepper motor sitting on the hub gearbox to
do the actual shifting. When I gave automating my Rohloff hub some
thought, I concluded that two stepper motors in the place of the
rotary control, each operating one cable, would give me electronically
assisted shifting. From experience with my Trek Cyber Nexus, I am not
impressed with electronic cables led to the rear hub, so if I ever do
it (no present plans; I'm waiting to see if my Rohloff runs in or I
get more used to it), I will leave the bowden cables to the handlebar
and simply slide the rotary control away a couple of inches, mount the
stepper motors in/on it, and put a toggle switch in its place under my
thumb, with a short cable to the stepper motors.

I don't think you can build any DIY system as cheaply as you can buy a
Shimano readymade system, unless you are already into electronics and
have junk box full of suitable parts like a dynohub, stepper motors of
a suitable size, lots of leftover Meccano from your childhood, and a
small lathe besides. See the wooden grip and clamp Tom Ace made for
his Rohloff, though.

HTH.

Andre Jute
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

Andre Jute wrote:
Speed, inclination and gear together give effort, indirectly as I
said.

....only if you neglect wind resistance.

--
MfG/Best regards
helmut springer panta rhei

"Helmut Springer" wrote in message
...
Andre Jute wrote:
Speed, inclination and gear together give effort, indirectly as I
said.

...only if you neglect wind resistance.

I think it's just speed and gear it plays with - doesn't need to be any more
complicated than that.

On Apr 28, 6:31*pm, Helmut Springer wrote:
Andre Jute wrote:
Speed, inclination and gear together give effort, indirectly as I
said.

...only if you neglect wind resistance.

--
MfG/Best regards
helmut springer * * * * * * * * * * * * * * * * * * * * * panta rhei

If there is a headwind, the cyclist slows down and the CPU puts him in
a lower gear so that his effort is the optimum he selected. If there
is a tailwind the cyclist travels faster and CPU puts him in a higher
gear and his effort again is the optimum he targets. This is exactly
the same concept as a racing cyclist changing gears to maintain his
cadence, which is his optimum energy expenditure.

Andre Jute
Simplicity is its own virtue

On 28 Apr 2009 18:22:32 GMT, wrote:

Clive George wrote:

Of course it calculates effort, to compare it to the effort level
chosen as a target, but it measures effort indirectly.

In which way?

There's a speed sensor in the dedicated hub dynamo of Shimano's
Cyber Nexus gruppo, and an inclination sensor somewhere.

Is there really an inclination sensor in there? I'd be interested to
see mention of it on a Shimano manual/website.

Deriving inclination on a vehicle moving at varying speed is an
illusive goal, gravitational and vehicle acceleration not being
separable. That is why assessing the gradient of a road is not
readily measured as users of altimeters that do that by averaging
climb per sampled distance. It doesn't work well, but better than
attempting it with an inclinometer that acts more like a cadence
pendulum than an inclinometer.

Jobst Brandt

Dear Jobst,

You don't even have to move to appreciate how silly the inclinometer
notion is. The bicycle has adjustable fore and aft suspension, with
inflatable tires.

Like any automatic transmission, Shimano's Cyber Nexus group uses no
inclinometer:

"This system is an automatic gear shifting system in which the
shifting points are determined by the speed of the bicycle (the
rotating speed of the wheels)."

http://cycle.shimano-eu.com/media/te...9830605819.pdf
or http://tinyurl.com/chumtd

The faster the front wheel spins, the higher the gear selected by the
automatic transmission. The PDF explains how the rider can adjust the
shift points and the suspension.

But there are, of course, no directions for adjusting imagininary
inclinometers.

Cheers,

Carl Fogel