What is Shimano smoking?

Chris Zacho 'The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine
my surprise when I ordered an LX derailer from Nashbar. and when it
came I saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

"Rapid Rise" rear derailers have been around for years. (Didn't know it was
available in LX, though.) Some people seem to love the reverse shifting
action; might take some getting used to, however.

Try it; you might like it... B

S o r n i said:

Chris Zacho 'The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine
my surprise when I ordered an LX derailer from Nashbar. and when it
came I saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

"Rapid Rise" rear derailers have been around for years. (Didn't know it was
available in LX, though.) Some people seem to love the reverse shifting
action; might take some getting used to, however.

Try it; you might like it... B

as many customers have figured out they don't want Rapid Rise Shimano
now calls it Low Normal
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Chris Zacho 'The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine

my

Quoted message said:

surprise when I ordered an LX derailer from Nashbar. and when it came

I

Quoted message said:

saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the

larger

Quoted message said:

cog?

Quoted message said:

From the Shimano website:

(http://tinyurl.com/kta8)

"Conventional rear derailleurs use spring pressure to pull the pulley
cage toward the higher gears. (smaller sprockets). This makes
up-shifting easy, but when you down-shift, the power input at shift
lever must overcome spring pressure and the resistance of the chain
moving to a larger sprocket. This is why down-shifts have always been
harder than up-shifts.

"The Rapid Rise-design uses a reverse arrangement in which the pressure
of the spring is applied in the donw-shifting direction, so shifting to
a lower gear becomes much easier, especially at slower pedaling
cadences.

"Rapid Rise also makes the operation of the rear derailleur shift lever
identical to the front, so the shift action is uniform and easier to
understand between front and rear derailleurs. "

So there.

Jeff

Chris Zacho The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine my
surprise when I ordered an LX derailer from Nashbar. and when it came I
saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

- -

"May you have the winds at your back,
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner

The best explanation I've heard is that allowing you to downshift with
the cable pull is good for mountain biking, and situations where you
need to make rapid downshifts to avoid stalling and losing balance.
Upshifting is in general more leisurely.

Chris Zacho said:

Anybody knows it takes more effort to shift a chain onto a larger
cog than drop it onto a smaller one. And that the cable can provide
more "shifting force" to the derailer than the return spring. Well
imagine my surprise when I ordered an LX derailer from Nashbar. and
when it came I saw that it was built BACKWARDS!

Quoted message said:

What _mechanical_ logic is there to making a derailer that [tries]
to use the return spring to make the more difficult shift onto the
larger cog?

I think this has its roots in the same reason sprocket ramps, indexed
and handlebar shift mechanisms were invented. Many bicyclists cannot
pedal one handed, so downtube shifters that could be pre-shifted to
larger sprockets without pedaling became a feature. Once it was there
the specter of crashing gears and breaking chains by forced downshifts
went away as well. You can't readily do much damage. Because
upshifting takes less skill and time, emphasis went to downshifting.

Jobst Brandt
[email hidden]

Chris Zacho The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine my
surprise when I ordered an LX derailer from Nashbar. and when it came I
saw that it was built BACKWARDS!

Actually, up until about 1960, all spring-loaded derailers worked this
way.

Quoted message said:

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

"Low-normal" rear derailers generally tend to downshift better than
comparable high-normal units, and to downshift better than they upshift.
This has always been the case. Since downshifting is the more
critical shift, it makes a lot of sense to return to the low-normal design.

It does take a bit of getting used to. I remember back in the early
'60s when I went from my low-normal Cyclo Benelux Mark VIII to a
newfangled Hurét Alvit (high-normal) it took quite a few miles to get
used to shifting in the opposite direction.

The Alvit and other parallelogram derailers were such an improvement
over the older coil-spring/plunger design that we tended to overlook the
fact that they didn't downshift as well as they upshifted, since they
did both better than the older units.

See also: http://sheldonbrown.com/gloss_l.html#lownormal

Marten Gerritsen said:

as many customers have figured out they don't want Rapid Rise Shimano
now calls it Low Normal

"Low normal" is the generic term, I guess Shimano decided they didn't
need to use a registered trademark for this rather desirable function.

Most folks who have actually ridden on these long enough to get used to
the opposite direction action wind up preferring it.

Now that there's no longer a need to double shift with downtube levers,
there isn't any reason to put up with the idiosyncracies of high-normal
rear derailers.

Sheldon "low Normal" Brown
+--------------------------------------------------+
| Pohl's law: Nothing is so good that somebody, |
| somewhere, will not hate it. |
+--------------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Chris Zacho The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine my
surprise when I ordered an LX derailer from Nashbar. and when it came I
saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

One more advantage to "low normal" - if you break your derailleur (I
make no apologies for my choice of spelling) cable on a "high normal"
you'll shift into your biggest gear and that makes it pretty tough to
get over the hill back home - and you'll be cross-chained too. Might be
able to do something with the high stop screw but maybe not.

OK, it only happened to me once, a very long time ago, but I'll never
forget it.

--
My bike blog:
http://diabloscott.blogspot.com/

Sheldon said:

Now that there's no longer a need to double shift with downtube

levers,

Quoted message said:

there isn't any reason to put up with the idiosyncracies of

high-normal

Quoted message said:

rear derailers.

Maybe I'm dense, and you're just referencing the current popularity of
brifters, but what has changed to preclude double shifting on downtube
levers? I double shifted my d/t shifted bike quite a few times
yesterday.

And though I'm not particularly a fan of low normal rear derailleurs, I
don't see why double-shifting one would be at all harder than not.
Just shove both levers forward or back instead of twisting your hand.

Or combine an LX low normal rear derailleur with a Suntour Spirt high
normal front derailleur.

- Christian

On Mon, 14 Mar 2005 15:24:14 -0500, [email hidden] (Chris

Zacho 'The Wheelman') may have said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine my
surprise when I ordered an LX derailer from Nashbar. and when it came I
saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the larger
cog?

Excuse me? Did you just ask what advantage there is in having a
spring attempt to help move the der in the direction in which the
greater force is needed?

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

I said:

Quoted message said:

Now that there's no longer a need to double shift with downtube
levers, there isn't any reason to put up with the idiosyncracies of
high-normal rear derailers.

Someone replied

Quoted message said:

Maybe I'm dense, and you're just referencing the current popularity of
brifters, but what has changed to preclude double shifting on downtube
levers?

Are there any new bikes with downtube shifters? None that I know of.
Virtually all bikes made in the past decade have had the controls on the
handlebars, where they belong.

Quoted message said:

And though I'm not particularly a fan of low normal rear derailleurs, I
don't see why double-shifting one would be at all harder than not.
Just shove both levers forward or back instead of twisting your hand.

It's the other way around. With high-normal rear and low-normal front
(or vice versa) you move both levers in the same direction to shift.
This is easier than twisting your hand to move one forward and the other
backward, as is necessary if you match the springing of front and rear
derailers.

Quoted message said:

Or combine an LX low normal rear derailleur with a Suntour Spirt high
normal front derailleur.

The Spirt has been extinct for about 30 years. There are no high normal
front derailers in current (or even recent) production.

Sheldon "Old Frames, New Parts" Brown
+-----------------------------------------+
| A ship in the harbor is safe, but |
| that is not what ships are built for. |
| --John A. Shedd |
+-----------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

"Diablo Scott" <[email hidden]> wrote in message
news:1110841739.d540aaa007003879565e8048d6a26c7b@teranews...

Quoted message said:

Chris Zacho The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine my
surprise when I ordered an LX derailer from Nashbar. and when it came I
saw that it was built BACKWARDS!

Shimano wants to build a completely self-contained bike built of Shimano
parts so it can start a monopoly and charge very high prices.

Werehatrack said:

On Mon, 14 Mar 2005 15:24:14 -0500, [email hidden] (Chris

Zacho 'The Wheelman') may have said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well
imagine my surprise when I ordered an LX derailer from Nashbar. and
when it came I saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the
larger cog?

Excuse me? Did you just ask what advantage there is in having a
spring attempt to help move the der in the direction in which the
greater force is needed?

It doesn't *help*... The spring is the ONLY force (other than cable/housing
friction) in this case. When one learns to shift properly, IMO, more
control is to be had with a high-normal rear derailleur.
--
Phil, Squid-in-Training

Sheldon Brown said:

Are there any new bikes with downtube shifters? None that I know of.

Quoted message said:

Virtually all bikes made in the past decade have had the controls on

the

Quoted message said:

handlebars, where they belong.

The Fuji League: http://www.fujibikes.com/2005/bikes.asp?id=14

25 pound aluminum road bike with compact geometry, an "aero" cromoly
fork, and downtube shifters... all those anachronsims for only $400.

-Vee

Can your brain get used to high normal on one bike when you have low
normal on another. I have four road bikes and was afraid to go to the
new style on one an not the others.

Chris Zacho 'The Wheelman said:

Anybody knows it takes more effort to shift a chain onto a larger cog
than drop it onto a smaller one. And that the cable can provide more
"shifting force" to the derailer than the return spring. Well imagine

my

Quoted message said:

surprise when I ordered an LX derailer from Nashbar. and when it came

I

Quoted message said:

saw that it was built BACKWARDS!

What _mechanical_ logic is there to making a derailer that [tries] to
use the return spring to make the more difficult shift onto the

larger

Quoted message said:

cog?

- -

"May you have the winds at your back,
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner

On 14 Mar 2005 17:24:46 -0800, "eflayer2" <[email hidden]> may

have said:

Can your brain get used to high normal on one bike when you have low
normal on another. I have four road bikes and was afraid to go to the
new style on one an not the others.

I can't say if yours can handle it, but mine can. YMMV.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

On Tue, 15 Mar 2005 00:01:48 GMT, "Phil, Squid-in-Training"

may have said:

It doesn't *help*... The spring is the ONLY force (other than cable/housing
friction) in this case. When one learns to shift properly, IMO, more
control is to be had with a high-normal rear derailleur.

Re-framing the inquiry, then; how is it bad to have a spring that's
chosen to be a good match for the required force to accomplish the
task instead of a user who may be yanking on the cable with more force
than required at the moment? Bear in mind that with a low-normal rear
der, if the shifter is moved toward the lower gear when the bike isn't
moving very fast, nothing is going to get overstressed.

I've got bikes with both types. I have come to prefer low-normal.
Have you tried it yet?

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

Sheldon Brown said:

Are there any new bikes with downtube shifters? None that I know of.

Quoted message said:

Virtually all bikes made in the past decade have had the controls on

the

Quoted message said:

handlebars, where they belong.

Granted that most complete bikes these days are sold with brifters, but
9 and even 10 speed downtube shifters are common enough to be sold by
both manufacturers. And my Pegoretti and Rivendell are of 2003 and
2004 vintage and have d/t braze-ons to allow the use of d/t shifters.
(And both have them.)

Quoted message said:

It's the other way around. With high-normal rear and low-normal

front

Quoted message said:

(or vice versa) you move both levers in the same direction to shift.
This is easier than twisting your hand to move one forward and the

other

Quoted message said:

backward, as is necessary if you match the springing of front and

rear

Quoted message said:

derailers.

Right, I think we're in agreement on this point. High normal rear
derailleurs, when combined with common front derailleurs seem to make
double shifting marginally easier, at least in theory. I've not found
a problem double shifting regular derailleurs either, though.

And for the person whose cable broke, you can always (well, in 99+% of
cases) pull the rear derailleur cable taught enough for a middle gear
and tie it off on the bottle cage bolt, if you don't want to fool with
the limit screws.

Cheers,
- Christian

An anonymous poster asked:

Quoted message said:

Can your brain get used to high normal on one bike when you have low
normal on another. I have four road bikes and was afraid to go to the
new style on one an not the others.

That's a real issue. I recently had to deal with this when I put
together a bike with one of the new Shimano Nexus 8-speed hubs. It came
with a twist-grip shifter that shifts in the opposite direction from the
default setting on my Rohloff 14 speed.

Fortunately, it was easy enough to cross the cables on the Rohloff so
that it matches the Nexus, and I'm now pretty well used to it.

The first modern bike I've ridden with a low-normal rear derailer was
the Rambouillet that Grant Petersen lent me while I was visiting NorCal
last October. This had bar-end shifters, which I'm not used to. I
liked the barcons a lot better with the low normal than I have when I've
ridden other bikes with barcons and high-normal rear mechs.

All and all, though, the adjustment isn't really any worse than going
back and forth between STI and Ergo shifters...but I couldn't handle
that either, which is why I ditched the STIs from my Hetchins.

Sheldon "Lo! Normal!" Brown
+--------------------------------------------+
| Nothing is given so profusely as advice. |
| - Francois, Duc de la Rouchefoucauld |
+--------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Sheldon Brown wrote:
There are no high normal

Quoted message said:

front derailers in current (or even recent) production.

fairly recent: Sachs Quartz (1996-)

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl