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won't shift to granny



 
 
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  #1  
Old May 4th 05, 01:37 PM
Kyle.B.H.
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Default won't shift to granny

I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t, and
the problem crept up again. I have already taken the measures of filing
away the portion of the derailer that conatcts the frame, filing a small
groove in the seat tube itself, and even moving my chainline outward
about a mm via a BB spacer, and still no success. It shifts fine when
not under load, but once you start up an incline, forget it, it won't
go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth in
the middle ring to aid the shift. Don't some chainrings include this as
a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?

Thanks,

Kyle
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  #2  
Old May 4th 05, 02:02 PM
Qui si parla Campagnolo
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Default


Kyle.B.H. wrote:
I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t,

and
the problem crept up again. I have already taken the measures of

filing
away the portion of the derailer that conatcts the frame, filing a

small
groove in the seat tube itself, and even moving my chainline outward
about a mm via a BB spacer, and still no success. It shifts fine

when
not under load, but once you start up an incline, forget it, it won't


go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth

in
the middle ring to aid the shift. Don't some chainrings include this

as
a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?

Thanks,

Kyle


Perhaps the 6603 front der which is designed for a 39t middle ring,
with the appropriate ramps to get the chain to the granny.

  #3  
Old May 4th 05, 02:03 PM
Peter Cole
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Posts: n/a
Default

Kyle.B.H. wrote:
I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t, and
the problem crept up again. I have already taken the measures of filing
away the portion of the derailer that conatcts the frame, filing a small
groove in the seat tube itself, and even moving my chainline outward
about a mm via a BB spacer, and still no success. It shifts fine when
not under load, but once you start up an incline, forget it, it won't
go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth in
the middle ring to aid the shift. Don't some chainrings include this as
a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?


Get a longer BB spindle.
  #4  
Old May 4th 05, 02:13 PM
Bill
external usenet poster
 
Posts: n/a
Default

"Qui si parla Campagnolo" wrote in message
oups.com...

Kyle.B.H. wrote:
I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t,

and
the problem crept up again. I have already taken the measures of

filing
away the portion of the derailer that conatcts the frame, filing a

small
groove in the seat tube itself, and even moving my chainline outward
about a mm via a BB spacer, and still no success. It shifts fine

when
not under load, but once you start up an incline, forget it, it won't


go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth

in
the middle ring to aid the shift. Don't some chainrings include this

as
a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?

Thanks,

Kyle


Perhaps the 6603 front der which is designed for a 39t middle ring,
with the appropriate ramps to get the chain to the granny.

I was under the impression that shifting the front "under load" wasn't a
plan.
Bill


  #5  
Old May 4th 05, 03:35 PM
Tim Lines
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Posts: n/a
Default

Qui si parla Campagnolo wrote:

Perhaps the 6603 front der which is designed for a 39t middle ring,
with the appropriate ramps to get the chain to the granny.


OH!

Last week I got a 6603 fd and was really surprised to find that it was
incompatible with my old 105 triple crank and chainrings (42t middle).
Now I know why it didn't work. Thanks!
  #6  
Old May 4th 05, 04:56 PM
Mike Jacoubowsky
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Posts: n/a
Default

I'm having problems (again) shifting from my middle to granny under load.
I just replaced my moderately worn 40t middle with a new 38t, and the
problem crept up again. I have already taken the measures of filing away
the portion of the derailer that conatcts the frame, filing a small groove
in the seat tube itself, and even moving my chainline outward about a mm
via a BB spacer, and still no success. It shifts fine when not under
load, but once you start up an incline, forget it, it won't go. Its an
Ultegra der. and TA Alize rings.


The greater the gap between the largest two chainrings, the more difficulty
there will be shifting from the middle to the smallest. That's an absolute
fact of life, regardless of what you may read elsewhere. That doesn't mean
you can't make it work better than it presently does (by using a derailleur
designed for a smaller middle chainring, such as Peter/Qui si parla
Campagnolo suggested). Or it might work better if you bring down the size of
the largest chainring, although at some point you have the curve of the
derailleur not matching up to the radius of the outer chainring, which will
also cause shifting issues.

With the DuraAce 9-speed triple (with 52/39/30), Shimano tried to get around
this by cutting down the profile of the teeth on the middle chainring.
Unfortunately, it was/is legendary for dumping the chain off the middle
chainring as you're "just riding along." The shifting was terrible compared
to the Ultegra 52/42/30. However, for the new Ultegra 10, they seem to have
gotten their act together and the 52/39/30 shifts quite nicely. Dramatic
improvement. But it also has a highly-convoluted middle chainring that would
be difficult to duplicate with your dremel tool, *and* will probably wear
out more quickly too.

Please note these problems are exacerbated by STI shifting, which doesn't
allow you to control the shifting process as much as Ergo or friction.
They're also far pickier about chain choice and, I daresay, if you're using
an SRAM chain, you may have better results with a Shimano.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com


"Kyle.B.H." wrote in message
...
I'm having problems (again) shifting from my middle to granny under load.
I just replaced my moderately worn 40t middle with a new 38t, and the
problem crept up again. I have already taken the measures of filing away
the portion of the derailer that conatcts the frame, filing a small groove
in the seat tube itself, and even moving my chainline outward about a mm
via a BB spacer, and still no success. It shifts fine when not under
load, but once you start up an incline, forget it, it won't go. Its an
Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth in
the middle ring to aid the shift. Don't some chainrings include this as a
feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm) would
I file the teeth?

C) Any other suggestions?

Thanks,

Kyle



  #7  
Old May 4th 05, 05:47 PM
Bill Sornson
external usenet poster
 
Posts: n/a
Default

Kyle.B.H. wrote:
I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t,
and the problem crept up again. I have already taken the measures of
filing away the portion of the derailer that conatcts the frame,
filing a small groove in the seat tube itself, and even moving my
chainline outward about a mm via a BB spacer, and still no success.
It shifts fine when not under load, but once you start up an incline,
forget it, it won't go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth
in the middle ring to aid the shift. Don't some chainrings include
this as a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?


Hate to say it, but what the hell. How about a "thumb adjustment"? (Place
both thumbs on the FD cage and push it inboard with a bit of force.) Or
just turn it in a tad the old-fashioned way (loosening bolt and adjusting
the clamp).

Also, try easing up on the pedal force just long enough to make the shift;
then resume suffering. (Err, mashing.)

Finally, like Mike said try a Shimano chain. I love SRAM PC-99s, but on my
road bike they were noisy and shifted a little clunkily compared to a Big S.

Bill (little) S.

PS: I got away with changing my Ultegra front crankset (52-42-30) to D-A
(53-39-30) without replacing my Ultegra FD; but then again, I gots strong
thumbs!


  #8  
Old May 5th 05, 12:52 AM
Jeff Starr
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Posts: n/a
Default

On Wed, 04 May 2005 15:56:28 GMT, "Mike Jacoubowsky"
wrote:


With the DuraAce 9-speed triple (with 52/39/30), Shimano tried to get around
this by cutting down the profile of the teeth on the middle chainring.
Unfortunately, it was/is legendary for dumping the chain off the middle
chainring as you're "just riding along." The shifting was terrible compared
to the Ultegra 52/42/30. However, for the new Ultegra 10, they seem to have
gotten their act together and the 52/39/30 shifts quite nicely. Dramatic
improvement. But it also has a highly-convoluted middle chainring that would
be difficult to duplicate with your dremel tool, *and* will probably wear
out more quickly too.

Please note these problems are exacerbated by STI shifting, which doesn't
allow you to control the shifting process as much as Ergo or friction.
They're also far pickier about chain choice and, I daresay, if you're using
an SRAM chain, you may have better results with a Shimano.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com



Mike, the DA 9-speed triple 7703 has a 53t large chainring. So, you
have 53/39/30.

I have about 3700 miles on my DA crankset and I have never had it dump
off from the middle chainring. Is this a problem that shows up with
use and wear, or if it is going to be a problem, does it happen right
from new?

One more thing to worry about?


Life is Good!
Jeff
  #9  
Old May 5th 05, 03:33 AM
Kyle.B.H.
external usenet poster
 
Posts: n/a
Default

Mike Jacoubowsky wrote:
I'm having problems (again) shifting from my middle to granny under load.
I just replaced my moderately worn 40t middle with a new 38t, and the
problem crept up again. I have already taken the measures of filing away
the portion of the derailer that conatcts the frame, filing a small groove
in the seat tube itself, and even moving my chainline outward about a mm
via a BB spacer, and still no success. It shifts fine when not under
load, but once you start up an incline, forget it, it won't go. Its an
Ultegra der. and TA Alize rings.



The greater the gap between the largest two chainrings, the more difficulty
there will be shifting from the middle to the smallest. That's an absolute
fact of life, regardless of what you may read elsewhere. That doesn't mean
you can't make it work better than it presently does (by using a derailleur
designed for a smaller middle chainring, such as Peter/Qui si parla
Campagnolo suggested). Or it might work better if you bring down the size of
the largest chainring, although at some point you have the curve of the
derailleur not matching up to the radius of the outer chainring, which will
also cause shifting issues.


Unfortunately, the large ring is already a 50.

With the DuraAce 9-speed triple (with 52/39/30), Shimano tried to get around
this by cutting down the profile of the teeth on the middle chainring.
Unfortunately, it was/is legendary for dumping the chain off the middle
chainring as you're "just riding along." The shifting was terrible compared
to the Ultegra 52/42/30. However, for the new Ultegra 10, they seem to have
gotten their act together and the 52/39/30 shifts quite nicely. Dramatic
improvement. But it also has a highly-convoluted middle chainring that would
be difficult to duplicate with your dremel tool, *and* will probably wear
out more quickly too.


Yeah, I'm hesitant to start dremeling teeth off of my $40 chainring.

I went to a bar-end friction shifter on my tourer and that may be the
solution here.


Please note these problems are exacerbated by STI shifting, which doesn't
allow you to control the shifting process as much as Ergo or friction.
They're also far pickier about chain choice and, I daresay, if you're using
an SRAM chain, you may have better results with a Shimano.


S'pose I could give it a try. I'll also probably try a 118 BB as
opposed to the 115 I've got on there now. I also wonder if its by front
der. braze-on - could not provide enough extenstion from the frame.

Thanks.


--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com


"Kyle.B.H." wrote in message
...

I'm having problems (again) shifting from my middle to granny under load.
I just replaced my moderately worn 40t middle with a new 38t, and the
problem crept up again. I have already taken the measures of filing away
the portion of the derailer that conatcts the frame, filing a small groove
in the seat tube itself, and even moving my chainline outward about a mm
via a BB spacer, and still no success. It shifts fine when not under
load, but once you start up an incline, forget it, it won't go. Its an
Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth in
the middle ring to aid the shift. Don't some chainrings include this as a
feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm) would
I file the teeth?

C) Any other suggestions?

Thanks,

Kyle




  #10  
Old May 5th 05, 03:34 AM
Kyle.B.H.
external usenet poster
 
Posts: n/a
Default

Bill wrote:
"Qui si parla Campagnolo" wrote in message
oups.com...

Kyle.B.H. wrote:

I'm having problems (again) shifting from my middle to granny under
load. I just replaced my moderately worn 40t middle with a new 38t,


and

the problem crept up again. I have already taken the measures of


filing

away the portion of the derailer that conatcts the frame, filing a


small

groove in the seat tube itself, and even moving my chainline outward
about a mm via a BB spacer, and still no success. It shifts fine


when

not under load, but once you start up an incline, forget it, it won't


go. Its an Ultegra der. and TA Alize rings.

So now I'm thinking I'll file the tops off of two consectutive teeth


in

the middle ring to aid the shift. Don't some chainrings include this


as

a feature?

A) Think this will help?

B) If I do this, where on the ring (relative to the right crankarm)
would I file the teeth?

C) Any other suggestions?

Thanks,

Kyle


Perhaps the 6603 front der which is designed for a 39t middle ring,
with the appropriate ramps to get the chain to the granny.


I was under the impression that shifting the front "under load" wasn't a
plan.
Bill


unfortunately, the need for the granny gear most often coincides with
the drivetrain being under at least some load, i.e. you're going up hill.
 




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