Dura Ace versus Ultegra triple

Okay, here I go again with my vague understanding or Shimano triple setups.
I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???
If so, does it have to be a special 39 ring?
Thanks.
Gary

Gary wrote:

Okay, here I go again with my vague understanding or Shimano triple setups.
I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???

Yes.

If so, does it have to be a special 39 ring?

Ideally you should have a ring made for the middle position, with helper
pins and ramps on the inner face to facilitate upshifting from the small
chainring.

TA of France makes suitable rings down to 38 teeth.

See: http://sheldonbrown.com/harris/chainrings.html#130

A plain, flat 38 or 39 could probably also work, but would likely
require a bit of technique to perform the upshift from small to middle.
If you have one kicking around in your parts box, no harm in trying, but
if you're going to buy a new ring go for a TA.

Sheldon "Custom Gearing" Brown
+--------------------------------------------------+
| I'm crazy about the music of Leos Janacek, |
| especially the Msa Glagolskaya and Sinfonietta |
| http://sheldonbrown.com/music.html |
+--------------------------------------------------+
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

Bless you. Thank you.

Sheldon Brown wrote:

Gary wrote:

Okay, here I go again with my vague understanding or Shimano triple
setups.
I read at the Shimano site (details on Dura Ace triple front
derailleur) that the MINIMUM drop from the large ring to the middle is
14 teeth. MINIMUM it said. That would seem to indicate I can't use the
Ultegra crankset I have with it. My question now is can I simply put a
39 ring in the middle of my ultegra triple crank to set up the
14-tooth drop???


Yes.

If so, does it have to be a special 39 ring?


Ideally you should have a ring made for the middle position, with helper
pins and ramps on the inner face to facilitate upshifting from the small
chainring.

TA of France makes suitable rings down to 38 teeth.

See: http://sheldonbrown.com/harris/chainrings.html#130

A plain, flat 38 or 39 could probably also work, but would likely
require a bit of technique to perform the upshift from small to middle.
If you have one kicking around in your parts box, no harm in trying, but
if you're going to buy a new ring go for a TA.

Sheldon "Custom Gearing" Brown
+--------------------------------------------------+
| I'm crazy about the music of Leos Janacek, |
| especially the Msa Glagolskaya and Sinfonietta |
| http://sheldonbrown.com/music.html |
+--------------------------------------------------+
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

Okay, here I go again with my vague understanding or Shimano triple
setups.
I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???
If so, does it have to be a special 39 ring?

I'm obviously at odds with the opinion of my esteemed colleague, but...

Our experiences, repeated many times, have been that customers switching
from a 42t middle to 39t on an Ultegra triple have found that shifting
performance definitely suffered. Some were willing to put up with the
degradation, while others have been very disappointed. Most frustrating to
me have been the number who feel that it ought to work and so, when it
doesn't meet their expectations, look for all manner of other things to
blame for the shifting problems, including frame alignment, bad chain or
simple misadjustment.

The most-popular chainring to use has been the pinned & ramped TA, which
will definitely give better results than a chainring not designed to be used
in the middle.

By the way, the difficult shift when changing the middle from a 42t to a 39t
will be from the middle chainring down to the smallest. There will also be
some degradation going from small to middle; in some cases, you'll find it
will want to shift all the way up to the largest (and then you'll need to
shift it back down).

--Mike-- Chain Reaction Bicycles
http://www.ChainReactionBicycles.com

Mike Jacoubowsky wrote:

Okay, here I go again with my vague understanding or Shimano triple

setups.

I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???
If so, does it have to be a special 39 ring?


I'm obviously at odds with the opinion of my esteemed colleague, but...

Our experiences, repeated many times, have been that customers switching
from a 42t middle to 39t on an Ultegra triple have found that shifting
performance definitely suffered.

I'm sure this would be the case with an _Ultegra_ front derailer, but my
understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Sheldon "Rarely Disagrees With Mike" Brown
+------------------------------------------------------+
| Sweet is the scene where genial friendship plays |
| The pleasing game of interchanging praise. |
| --Oliver Wendell Holmes Sr. |
+------------------------------------------------------+
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

Yes, I was speaking of using a DA F.D.
Gary

Sheldon Brown wrote:
Mike Jacoubowsky wrote:

Okay, here I go again with my vague understanding or Shimano triple


setups.

I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???
If so, does it have to be a special 39 ring?



I'm obviously at odds with the opinion of my esteemed colleague, but...

Our experiences, repeated many times, have been that customers switching
from a 42t middle to 39t on an Ultegra triple have found that shifting
performance definitely suffered.


I'm sure this would be the case with an _Ultegra_ front derailer, but my
understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Sheldon "Rarely Disagrees With Mike" Brown
+------------------------------------------------------+
| Sweet is the scene where genial friendship plays |
| The pleasing game of interchanging praise. |
| --Oliver Wendell Holmes Sr. |
+------------------------------------------------------+
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

FSA also makes a ramp/pin 39t, but it is black/silver teeth.
Tom

--
Bruni Bicycles
"Where art meets science"
brunibicycles.com
410.426.3420
Gary wrote in message
...
Yes, I was speaking of using a DA F.D.
Gary

Sheldon Brown wrote:
Mike Jacoubowsky wrote:

Okay, here I go again with my vague understanding or Shimano triple


setups.

I read at the Shimano site (details on Dura Ace triple front
derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth
drop???
If so, does it have to be a special 39 ring?



I'm obviously at odds with the opinion of my esteemed colleague, but...

Our experiences, repeated many times, have been that customers
switching
from a 42t middle to 39t on an Ultegra triple have found that shifting
performance definitely suffered.


I'm sure this would be the case with an _Ultegra_ front derailer, but my
understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Sheldon "Rarely Disagrees With Mike" Brown
+------------------------------------------------------+
| Sweet is the scene where genial friendship plays |
| The pleasing game of interchanging praise. |
| --Oliver Wendell Holmes Sr. |
+------------------------------------------------------+
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

I'm sure this would be the case with an _Ultegra_ front derailer, but my
understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Yes, you're correct; I shouldn't read or answer emails while I'm thinking
about my daughter getting a driver's license tomorrow.

With a DuraAce, obviously the front derailleur is made with the 39t in mind;
the only issue might be that it's designed with a trim function in all three
chainrings, not just the smaller two as found on the Ultegra.

Be afraid. Be very afraid. (Not of the derailleur issue; I'm talking about
the roadways around here after tomorrow morning!). Any recommendations on a
car for her? I'm thinkin' 1990-ish Toyota Corolla or Honda Civic.

And now back to the bicycle shop, which is already in progress...

--Mike-- Chain Reaction Bicycles
http://www.ChainReactionBicycles.com


"Sheldon Brown" wrote in message
...
Mike Jacoubowsky wrote:

Okay, here I go again with my vague understanding or Shimano triple

setups.

I read at the Shimano site (details on Dura Ace triple front derailleur)
that the MINIMUM drop from the large ring to the middle is 14 teeth.
MINIMUM it said. That would seem to indicate I can't use the Ultegra
crankset I have with it. My question now is can I simply put a 39 ring
in the middle of my ultegra triple crank to set up the 14-tooth drop???
If so, does it have to be a special 39 ring?


I'm obviously at odds with the opinion of my esteemed colleague, but...

Our experiences, repeated many times, have been that customers switching
from a 42t middle to 39t on an Ultegra triple have found that shifting
performance definitely suffered.

I'm sure this would be the case with an _Ultegra_ front derailer, but my
understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Sheldon "Rarely Disagrees With Mike" Brown
+------------------------------------------------------+
| Sweet is the scene where genial friendship plays |
| The pleasing game of interchanging praise. |
| --Oliver Wendell Holmes Sr. |
+------------------------------------------------------+
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:

I'm sure this would be the case with an _Ultegra_ front derailer, but
my understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?


Am I right in assuming this debate has the presumption of a STi shifter for
the front mech. and with a downtube friction shifter there is no real issue
due to the fine adjustment being available ?

"MSeries" wrote in news:btv0to$brno1$1@ID-
207671.news.uni-berlin.de:
I'm sure this would be the case with an _Ultegra_ front derailer, but
my understanding was that original poster was speaking of using a
_Dura-Ace_ triple mech...?

Am I right in assuming this debate has the presumption of a STi shifter for
the front mech. and with a downtube friction shifter there is no real issue
due to the fine adjustment being available ?

Dura-Ace triple front derailleur has a taller cage, so it works better than
Ultegra with a bigger spread between the middle and big chainrings.