A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » Techniques
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Rohloff makes the case for Cyber Nexus



 
 
Thread Tools Display Modes
  #1  
Old April 27th 09, 10:02 PM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default Rohloff makes the case for Cyber Nexus

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.

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

Ads
  #2  
Old April 28th 09, 12:37 AM posted to rec.bicycles.tech
(PeteCresswell)
external usenet poster
 
Posts: 2,790
Default Rohloff makes the case for Cyber Nexus

Per Andre Jute:

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


It might be a personality thing.

I tried somebody's automatic-shifting bike once and it drove me
nuts. OTOH, the guy whose bike it was loved it.

Sometimes I want high RPMs, other times I want low RPMS (as in
giving my butt a break going up hill)... regardless of ground
speed.
--
PeteCresswell
  #3  
Old April 28th 09, 01:11 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default Rohloff makes the case for Cyber Nexus

On Apr 28, 12:37*am, "(PeteCresswell)" wrote:
Per Andre Jute:



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


It might be a personality thing. *


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

I tried somebody's automatic-shifting bike once and it drove me
nuts. * OTOH, the guy whose bike it was loved it.


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

Sometimes I want high RPMs, other times I want low RPMS (as in
giving my butt a break going up hill)... regardless of ground
speed.


That's just what you're used to on derailleur bikes. You need more
than a short ride to get used to the auto box -- certainly I did, even
coming to it from the same type of Shimano box, only manual.

But, perhaps surprisingly after disagreeing with each of your
subsidiary points, I agree with your overall point. Shimano set up the
Cyber Nexus controls so that the "effort level control" is under the
bottom tube, facing down to the road, way out of reach. They want you
to set it once and forget it.

So, if you can't get used to a steady cadence with the gearbox
adapting, the Shimano implementation of full auto, as in the Cyber
Nexus, is not for you. I also corresponded with a guy who had the
derailleur type Shimano full auto on a Koga-Miyata, and he thought the
effort control should be under his thumb. (Too complicated for most
riders, I thought at the time, agreeing with Shimano.)

An alternative is CVT which, with your cadence, puts effort control
right under your thumb, as in the Fallbrook NuVinci CVT. Chalo several
times mentioned the high weight of the NuVinci hub but I don't see the
problem; it is clearly a commuter/daytourer's hub, so the weight
doesn't matter all that much.

Can't imagine racers of any kind looking at the hefty NuVinci though.

Andre Jute
You can ride only one bike at a time


  #4  
Old April 28th 09, 01:32 AM posted to rec.bicycles.tech
John Henderson
external usenet poster
 
Posts: 413
Default Rohloff makes the case for Cyber Nexus

(PeteCresswell) wrote:

I tried somebody's automatic-shifting bike once and it drove me
nuts. OTOH, the guy whose bike it was loved it.


I have a bike which came with a Shimano automatic hub (4-speed).

I persevered with it for a few months, and hated it - not the
lack of gears, but the infuriating changing when I didn't want it
to.

A bit like automatic cars really. I've driven one at least
weekly for many years, and still dislike that intensely.

So I bought a SRAM Spectro S7 for the bike and fitted it instead.

It's now 30,000 happy kilometres later.

John
  #5  
Old April 28th 09, 01:36 AM posted to rec.bicycles.tech
Tom Ace
external usenet poster
 
Posts: 391
Default Rohloff makes the case for Cyber Nexus

On Apr 27, 5:11*pm, Andre Jute wrote:

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


It might be a personality thing. *


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

Oh great. In addition to weight weenies, we can have seconds weenies.


An alternative is CVT which, with your cadence, puts effort control
right under your thumb, as in the Fallbrook NuVinci CVT. Chalo several
times mentioned the high weight of the NuVinci hub but I don't see the
problem; it is clearly a commuter/daytourer's hub, so the weight
doesn't matter all that much.


It's not just the weight, it's the efficiency of the NuVinci too.


In any case, I'm with Pete Cresswell. I'd much rather choose
when to shift.

Does the CyberNexus know to shift at the dead points
of the pedaling cycle (cranks near vertical) ?

Shifting the Rohloff reminds me of releasing a camera
shutter (rangefinder, not SLR) -- not in terms of the
effort required, but in the sound and in how quickly it happens.
(Full disclosu I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)

Tom Ace





  #6  
Old April 28th 09, 02:02 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default Rohloff makes the case for Cyber Nexus

On Apr 28, 1:36*am, Tom Ace wrote:
On Apr 27, 5:11*pm, Andre Jute wrote:

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


It might be a personality thing. *


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


Oh great. *In addition to weight weenies, we can have seconds weenies.


I used to have a fancy Ciclosport HAC4 (it broke a week or so after it
ran out of warranty and I decided not to replace it because it just
wasn't worth the EUR300 it cost back then). Among its facilities was a
comparative laptimer, and you could download data to the computer to
draw fancy graphs. I discovered that when I switched from Shimano
Nexus 8 speed to the Cyber Nexus, same but auto, I cut about ten per
cent off the shortest ride I did, even after I adjusted the overall
effort control precisely to give me the same respiration rate at
various points along a ride I took four or five days a week. There's
nothing to account for it except that the gears are automatic and
worked better than my (admittedly slack) gearchanging on the directly
comparable bike except for manual gears that went before.

An alternative is CVT which, with your cadence, puts effort control
right under your thumb, as in the Fallbrook NuVinci CVT. Chalo several
times mentioned the high weight of the NuVinci hub but I don't see the
problem; it is clearly a commuter/daytourer's hub, so the weight
doesn't matter all that much.


It's not just the weight, it's the efficiency of the NuVinci too.

In any case, I'm with Pete Cresswell. *I'd much rather choose
when to shift.

Does the CyberNexus know to shift at the dead points
of the pedaling cycle (cranks near vertical) ?


No. It's a very simple system really, which is possibly what makes it
work so well. I measures speed and inclination and takes in the
constant of the effort level the cyclist has chosen. Its adjustment
method is to change earlier or later to maintain that effort level.
Its genesis is clearly in racing cadence control. It is almost as if
Shimano knew that one day they would put a cut down version in a
premium Dura-Ace group.

Shifting the Rohloff reminds me of releasing a camera
shutter (rangefinder, not SLR) -- not in terms of the
effort required, but in the sound and in how quickly it happens.
(Full disclosu *I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)


This is interesting; the control is my least favourite part of the
Rohloff (next to the kinesthetic "feature" of the agricultural way it
works). Why did you make your own control? Does it have any advantage
for other bicyclists?

Andre Jute
http://www.audio-talk.co.uk/fiultra/Andre%20Jute's%20Utopia%20Kranich.pdf
  #7  
Old April 28th 09, 02:59 AM posted to rec.bicycles.tech
RonSonic
external usenet poster
 
Posts: 2,658
Default Rohloff makes the case for Cyber Nexus

On Mon, 27 Apr 2009 17:36:33 -0700 (PDT), Tom Ace wrote:

On Apr 27, 5:11*pm, Andre Jute wrote:

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


It might be a personality thing. *


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


Oh great. In addition to weight weenies, we can have seconds weenies.


Humans can anticipate the need to shift so there's no need to count seconds.

  #8  
Old April 28th 09, 03:39 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default Rohloff makes the case for Cyber Nexus

Ignore this part of the exchange, Tom:
(Full disclosu I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)


This is interesting; the control is my least favourite part of the
Rohloff (next to the kinesthetic "feature" of the agricultural way it
works). Why did you make your own control? Does it have any advantage
for other bicyclists?


I found your site and saw your DIY Rohloff shifter grip; answers my
questions. -- AJ

On Apr 28, 2:02*am, Andre Jute wrote:
On Apr 28, 1:36*am, Tom Ace wrote:

On Apr 27, 5:11*pm, Andre Jute wrote:


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


It might be a personality thing. *


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


Oh great. *In addition to weight weenies, we can have seconds weenies..


I used to have a fancy Ciclosport HAC4 (it broke a week or so after it
ran out of warranty and I decided not to replace it because it just
wasn't worth the EUR300 it cost back then). Among its facilities was a
comparative laptimer, and you could download data to the computer to
draw fancy graphs. I discovered that when I switched from Shimano
Nexus 8 speed to the Cyber Nexus, same but auto, I cut about ten per
cent off the shortest ride I did, even after I adjusted the overall
effort control precisely to give me the same respiration rate at
various points along a ride I took four or five days a week. There's
nothing to account for it except that the gears are automatic and
worked better than my (admittedly slack) gearchanging on the directly
comparable bike except for manual gears that went before.

An alternative is CVT which, with your cadence, puts effort control
right under your thumb, as in the Fallbrook NuVinci CVT. Chalo several
times mentioned the high weight of the NuVinci hub but I don't see the
problem; it is clearly a commuter/daytourer's hub, so the weight
doesn't matter all that much.


It's not just the weight, it's the efficiency of the NuVinci too.


In any case, I'm with Pete Cresswell. *I'd much rather choose
when to shift.


Does the CyberNexus know to shift at the dead points
of the pedaling cycle (cranks near vertical) ?


No. It's a very simple system really, which is possibly what makes it
work so well. I measures speed and inclination and takes in the
constant of the effort level the cyclist has chosen. Its adjustment
method is to change earlier or later to maintain that effort level.
Its genesis is clearly in racing cadence control. It is almost as if
Shimano knew that one day they would put a cut down version in a
premium Dura-Ace group.

Shifting the Rohloff reminds me of releasing a camera
shutter (rangefinder, not SLR) -- not in terms of the
effort required, but in the sound and in how quickly it happens.
(Full disclosu *I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)


This is interesting; the control is my least favourite part of the
Rohloff (next to the kinesthetic "feature" of the agricultural way it
works). Why did you make your own control? Does it have any advantage
for other bicyclists?

Andre Jute
*http://www.audio-talk.co.uk/fiultra/Andre%20Jute's%20Utopia%20Kranich....


  #9  
Old April 28th 09, 04:09 AM posted to rec.bicycles.tech
Tom Ace
external usenet poster
 
Posts: 391
Default Rohloff makes the case for Cyber Nexus

On Apr 27, 6:02*pm, Andre Jute wrote:

No. It's a very simple system really, which is possibly what makes it
work so well. I measures speed and inclination and takes in the
constant of the effort level the cyclist has chosen.


If it truly measures inclination rather than effort,
I'm even less interested in it. I mean, are you
saying headwind or tailwind has no effect on
what gear it selects?

(Full disclosu *I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)


This is interesting; the control is my least favourite part of the
Rohloff (next to the kinesthetic "feature" of the agricultural way it
works). Why did you make your own control? Does it have any advantage
for other bicyclists?


I made my own control to use on drop bars; the third-party
http://www.mittelmeyer.de/html/rennlenker.htm
shifter wasn't available yet.

Mine differs from the Rohloff shifter in having a cylindrical
rather than rounded-triangular grip. To reduce shifting
effort, I made the sections where the cables wrap smaller
in diameter than in the stock unit (I couldn't change that by
much though, I had to keep total rotation under 360 degrees).

Tom Ace
  #10  
Old April 28th 09, 04:25 AM posted to rec.bicycles.tech
Andre Jute[_2_]
external usenet poster
 
Posts: 10,422
Default Rohloff makes the case for Cyber Nexus

On Apr 28, 4:09*am, Tom Ace wrote:
On Apr 27, 6:02*pm, Andre Jute wrote:

No. It's a very simple system really, which is possibly what makes it
work so well. I measures speed and inclination and takes in the
constant of the effort level the cyclist has chosen.


If it truly measures inclination


It measures inclination for sure. Part of the Cyber Nexus Groupset is
a a suspended fork (the best fork I've ever had or ridden even without
the electronics) which locks up on hills and also when you're just
starting off from standstill, but goes softer when moving smoothly on
the level or downhill.

rather than effort,


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

I'm even less interested in it. * I mean, are you
saying headwind or tailwind has no effect on
what gear it selects?


A headwind and a tailwind affects the rider, and whatever affects the
rider causes the gearbox to react. In a tailwind he pedals slower. The
gearbox changes down so he can pedal faster and expend the effort
level he selected to be the overall control. With a tailwind he pedals
faster and the gearbox changes up.

HTH.

Andre Jute
"The brain of an engineer is a delicate instrument instrument which
must be protected against the unevenness of the ground." -- Wifredo-
Pelayo Ricart Medina

(Full disclosu *I made my own Rohloff shifter, but I'd
have the same comments if I were using the stock control.)


This is interesting; the control is my least favourite part of the
Rohloff (next to the kinesthetic "feature" of the agricultural way it
works). Why did you make your own control? Does it have any advantage
for other bicyclists?


I made my own control to use on drop bars; the third-partyhttp://www.mittelmeyer.de/html/rennlenker.htm
shifter wasn't available yet.

Mine differs from the Rohloff shifter in having a cylindrical
rather than rounded-triangular grip. *To reduce shifting
effort, I made the sections where the cables wrap smaller
in diameter than in the stock unit (I couldn't change that by
much though, I had to keep total rotation under 360 degrees).

Tom Ace


 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
WTB: Gear case or partial chain cover for bike with Nexus drive WC Handy Marketplace 0 July 21st 08 01:44 PM
Rohloff non-OEM hub in Rohloff OEM frame? Konstantin Shemyak Techniques 3 October 19th 06 02:31 PM
What airline bike case to buy? (Trico Iron Case or XPORT Cargo Case?) Robert Hayden General 2 July 14th 06 04:26 PM
Commonwealth Games Ballot - question about cyber-scalping Walrus Australia 8 June 1st 05 02:43 AM
S&S travel bike-their hard case or the soft case? eflayer2 Techniques 11 February 12th 05 01:07 AM


All times are GMT +1. The time now is 02:19 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
Copyright 2004-2022 CycleBanter.com.
The comments are property of their posters.