"Double" Rear Deraileur with Tripe Crank....does it matter

My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple crankset.
They said it doesn't matter, but I've noticed when in the smallest chainring and cog that the cage
comes all the way up and actually presses against the body of the deraileur. I've asked them to
replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it really doesn't
matter. Does it matter?

 

Joe Gilmore wrote:
>
>
> Does it matter?

Yup!

A triple needs a longer chain. The longer cage of a long cage rear der allows it to take up more
chain when necessary. Get the correct part.

Barry

 

I don't think I've ever tried it. Not knowingly, that is. The Sh. 600 i presently have on my tourer
I got at a swap meet. It handles the triple fine, it certainly has enough swing, but the cage
doesn't look like a triple cage.

It actually fits the four tooth difference of my middle and outer rings. A true half step/Granny
derailleur? Did Shimano make a 600 like that?

I'd like to hear the answer to this one myself. It could be a nice addition to my "MacGyverisms"
column....

May you have the wind at your back. And a really low gear for the hills! Chris

Chris'Z Corner "The Website for the Common Bicyclist": http://www.geocities.com/czcorner

 

"Joe Gilmore" <[email protected]> wrote:
>My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple crankset.
>They said it doesn't matter, but I've noticed when in the smallest chainring and cog that the cage
>comes all the way up and actually presses against the body of the deraileur. I've asked them to
>replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it really doesn't
>matter. Does it matter?

YES! Tell the bozo's at that shop that you want the RIGHT (long cage) der. put on and, after that's
accomplished, never go to that shop again!

 

Joe Gilmore wrote:
>
> My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
> crankset. They said it doesn't matter, but I've noticed when in the smallest chainring and cog
> that the cage comes all the way up and actually presses against the body of the deraileur. I've
> asked them to replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it
> really doesn't matter. Does it matter?

depends on the cogset. It will work with a close ratio block, but with wider ratio's the
chaintensioner can't cope
--
Marten

 

joe-<< My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
crankset. They said it doesn't matter

But- << but I've noticed when in the smallest chainring and cog that the cage comes all the way up
and actually presses against the body of the deraileur.

You can make it work with a short cage rear der but you often have to shorten the chain so much to
prevent cog to pulley noise in the bigger cogs/smallest ring(even with the b limit all the way in),
you end up with not enough chain for big-big combos.

It DOES matter, have your bike shop do it the way you want it.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

In article <[email protected]>,
"Joe Gilmore" <[email protected]> wrote:

> My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
> crankset. They said it doesn't matter, but I've noticed when in the smallest chainring and cog
> that the cage comes all the way up and actually presses against the body of the deraileur.

Well, some say you should never be simultaneously in your smallest (or smaller) chain ring and cogs.

 

My '91 Trek 1420 came geared 50x45x28 and the front derailleur was a Deore DX. Muzi has told me that
in those years, there was a choice of 2 models for ½ step and regular.

On Sat, 26 Apr 2003 18:29:11 -0400 (EDT), [email protected] (Chris Zacho "The Wheelman") wrote:

>It actually fits the four tooth difference of my middle and outer rings. A true half step/Granny
>derailleur? Did Shimano make a 600 like that?

 

In article <[email protected]>, Paul Kopit <[email protected]> wrote:
>My '91 Trek 1420 came geared 50x45x28 and the front derailleur was a Deore DX. Muzi has told me
>that in those years, there was a choice of 2 models for ½ step and regular.

Correct - they used to put a sticker on the MTB version that said "alpine".

--Paul

 

"Joe Gilmore" <[email protected]> wrote in message
news:<[email protected]>...
> My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
> crankset. They said it doesn't matter, but I've noticed when in the smallest chainring and cog
> that the cage comes all the way up and actually presses against the body of the deraileur. I've
> asked them to replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it
> really doesn't matter. Does it matter?

.............Every road triple I have is set up with a short cage RD. Size the chain to accomodate
the big/big. Due to insufficient wrap capacity there will be some small sogs that may not be usable
depending on your tooth spead and derailer wrap capacity. I only use the granny as a bailout with
usually the 4 or 5 largest cogs so inadequate wrap is not an issue. You should not be in the smaller
cogs with a granny ring anyway.I have one setup that will wrap all the chain even in the small small
with an 8 speed DA short cage.

 

> On Sat, 26 Apr 2003 18:29:11 -0400 (EDT), [email protected] (Chris Zacho "The
> Wheelman") wrote:
> >It actually fits the four tooth difference of my middle and outer rings. A true half step/Granny
> >derailleur? Did Shimano make a 600 like that?

"Paul Kopit" <[email protected]> wrote in message
news:[email protected]...
> My '91 Trek 1420 came geared 50x45x28 and the front derailleur was a Deore DX. Muzi has told me
> that in those years, there was a choice of 2 models for ½ step and regular.

Right. The Deore DX and XT came in "alpine" and "half step" versions with a sticker on the cage
denoting the style. I don't think there was a 600 half-step or I never saw one.

--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971

 

On Sat, 26 Apr 2003 18:18:51 +0000, Joe Gilmore wrote:

> My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
> crankset. They said it doesn't matter,

Bullshit

> I've asked them to replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it
> really doesn't matter. Does it matter?

Of course it matters. No way will that double derailleur have enough capacity for a triple. In the
granny ring, most cogs will be unusable, and you are likely to throw a chain. Or, even worse, if the
chain is so short that that doesn't happen, you will not be able to shift into the largest cogs in
the big ring. Mistakes happen, and you will eventually shift where you are not supposed to, and
break something.

--

David L. Johnson

__o | Arguing with an engineer is like mud wrestling with a pig... You _`\(,_ | soon find out the
pig likes it! (_)/ (_) |

 

Joe Gilmore asked:
>
>>My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
>>crankset. They said it doesn't matter,

>>I've asked them to replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it
>>really doesn't matter. Does it matter?

Someone who wanted to be helpful overstated:

> Of course it matters. No way will that double derailleur have enough capacity for a triple. In the
> granny ring, most cogs will be unusable,

"Most cogs" _shouldn't_ be used with the granny ring, so if you have good shifting habits, it
won't matter.

> and you are likely to throw a chain.

I don't believe ther's any greater risk of throwing the chain. Worst case is that if he accidentally
shifts into one of the smaller rear cogs while on the granny ring, the chain will droop.

> Or, even worse, if the chain is so short that that doesn't happen, you will not be able to shift
> into the largest cogs in the big ring. Mistakes happen, and you will eventually shift where you
> are not supposed to, and break something.

Certainly nobody should ride with a chain that is too short, but that has nothing to do with
derailer choice.

I would say, as a general rule, that if you _need_ a new derailer, you might as well get a
long-cage one if you have a triple chainring, but I commonly do upgrades where I convert doubles to
triples, and leave the original short cage derailer, if the customer isn't going to a seriously low
gear in back.

Indeed, my Hetchins is running a current-model Dura-Ace rear derailer with a 12-28 cassette and a
50-28 chainset, works fine for me. (I don't use the 28 in front with any of the smaller rear
sprockets, though.)

Sheldon "It Works" Brown +-----------------------------------------------------------+
| Always listen to the experts. | They'll tell you what can't be done, and why. | Then do it.
| --Robert A. Heinlein |
+-----------------------------------------------------------+ 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

 

canwine-<< Well, some say you should never be simultaneously in your smallest (or smaller) chain
ring and cogs.

And you should 'never' leave the stop light in your car in 3rd, instead of first gear on a manual,
but of course, lots of people make this 'mistake'. As Mike J has correctly pointed out, at the end
of the day, last stretch before you get off the bike, slight uphill, tired and you mistakenly go
big-big, and break a chain...

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

'bikeman'-<< Every road triple I have is set up with a short cage RD. Size the chain to accomodate
the big/big.

But what do ya do in small ring and biggest cogs, with the b limit all the way in and sometimes
turned around and get the 'noise' of the pulley dragging on the cog?

Only way to fix this is shorten the chain to move the upper cage out of the way, which makes for a
too short chain for big, big.

With the abundance of road and MTB mid to long cage rear ders(DA, Record as well) there is NO
reason to use a short cage rear der on a triple...Saying that the lower mass 'shifts more crisply'
is bugle oil.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

On 27 Apr 2003 17:29:03 -0700, [email protected] (J. Price) wrote:

>"Joe Gilmore" <[email protected]> wrote in message
>news:<[email protected]>...
>> My LBS installed a "double" (short, not long cage) rear deraileur on a bike with a triple
>> crankset. They said it doesn't matter, but I've noticed when in the smallest chainring and cog
>> that the cage comes all the way up and actually presses against the body of the deraileur. I've
>> asked them to replace with a "triple" rear deraileur but I don't want to be "hardnosed" if it
>> really doesn't matter. Does it matter?
>
When I got a new mountain bike, I converted my old XTR bike to a kind of city bike by puting a rigid
fork, 1.50 slicks, and a 12-23 cassette on it. Rear shifting was sloppy until I put on an Ultegra
double rd which works perfectly. Of course, the old rd may have been worn and the close ratio
cassette does't stretch the derailleur's capacity as much.

 

In article <[email protected]>, Qui si parla Campagnolo
<[email protected]> wrote:
>canwine-<< Well, some say you should never be simultaneously in your smallest (or smaller) chain
>ring and cogs.
>
>And you should 'never' leave the stop light in your car in 3rd, instead of first gear on a manual,
>but of course, lots of people make this 'mistake'. As Mike J has correctly pointed out, at the end
>of the day, last stretch before you get off the bike, slight uphill, tired and you mistakenly go
>big-big, and break a chain...

I can't tell you how many times I have seen some poor sod wheel his cannondale into the repair area
and you see the derailleur in the spokes with the tab still attached after it ripped off the back of
the dropout, yanked off when the chain went to maximum tension. Not always impossible to fix but
sometimes barely worth the bother and parts.

--Paul

 

<snip for brevity>

I would say, as a general rule, that if you _need_ a new derailer, you
> might as well get a long-cage one if you have a triple chainring, but I commonly do upgrades where
> I convert doubles to triples, and leave the original short cage derailer, if the customer isn't
> going to a seriously low gear in back.
>
I've had mtn bikes with triples and road rear derailleurs before they all seemed to work fine. The
trick is to not run a cassette too big for the rear derailleur to wrap.

My advice: try it out and see if there are any problems before really bitching at the shop. We here
on the 'net don't know your specifics, the shop does. If the combo you have now doesn't perform
adequately, THEN have the shop put on a triple derailleur.

Mike

 

[email protected] (Qui si parla Campagnolo) wrote in message
news:<[email protected]>...
> 'bikeman'-<< Every road triple I have is set up with a short cage RD. Size the chain to accomodate
> the big/big.
>
> But what do ya do in small ring and biggest cogs, with the b limit all the way in and sometimes
> turned around and get the 'noise' of the pulley dragging on the cog?
>
> Only way to fix this is shorten the chain to move the upper cage out of the way, which makes for a
> too short chain for big, big.
>
> With the abundance of road and MTB mid to long cage rear ders(DA, Record as well) there is NO
> reason to use a short cage rear der on a triple...Saying that the lower mass 'shifts more crisply'
> is bugle oil.
>
>
> Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
> (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

.............I duno where you are coming from,as that aspect with the B tension and chain has never
been an issue. the "B" tension screw is in the same position it would be for a 23 cog on a double
setup.....I never said or implied the short cage actually shited better. I just do it because I
can,it works, and does simplify my inventory control.It also seem to drive some people nuts.

 

Dave Smith wrote:
>
> When I got a new mountain bike, I converted my old XTR bike to a kind of city bike by puting a
> rigid fork, 1.50 slicks, and a 12-23 cassette on it. Rear shifting was sloppy until I put on an
> Ultegra double rd which works perfectly. Of course, the old rd may have been worn and the close
> ratio cassette does't stretch the derailleur's capacity as much.

Did you shorten the chain when you installed the 12-23?

Barry