Front derailleur rigidity

The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures of
rigidity of various front derailleurs? Maybe some tests performed by
some bicycle magazine? I would prefer heavier but more rigid.

"Vladimir" wrote in message
om...
The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures of
rigidity of various front derailleurs? Maybe some tests performed by
some bicycle magazine? I would prefer heavier but more rigid.

I had the same problem. The problem was solved when I replaced the top swing
model (XT) with a downswing model (XT).

Lou

"Vladimir" wrote in message
om...
The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures of
rigidity of various front derailleurs? Maybe some tests performed by
some bicycle magazine? I would prefer heavier but more rigid.

I had the same problem. The problem was solved when I replaced the top swing
model (XT) with a downswing model (XT).

Lou

On 5 Oct 2004 00:21:09 -0700, (Vladimir) wrote:

The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures of
rigidity of various front derailleurs? Maybe some tests performed by
some bicycle magazine? I would prefer heavier but more rigid.

Or how about not shifting under load?

Or am I just being old-fashioned and don't know how bikes work nowadays?

I'm not _really_ trying to be a smart ass.

Ron

On 5 Oct 2004 00:21:09 -0700, (Vladimir) wrote:

The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures of
rigidity of various front derailleurs? Maybe some tests performed by
some bicycle magazine? I would prefer heavier but more rigid.

Or how about not shifting under load?

Or am I just being old-fashioned and don't know how bikes work nowadays?

I'm not _really_ trying to be a smart ass.

Ron

Ronsonic wrote:
On 5 Oct 2004 00:21:09 -0700, (Vladimir)
wrote:

The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures
of rigidity of various front derailleurs? Maybe some tests performed
by some bicycle magazine? I would prefer heavier but more rigid.

Or how about not shifting under load?

Or am I just being old-fashioned and don't know how bikes work
nowadays?

No... this is a technique that all should learn. Shifting to a larger
chainring is less of an issue because one can use finger pressure to force
the shift.

Deores will wear out rapidly, however. My 1-season Deore has sloppy pivots,
and I rarely shift... the whole thing rattles like crazy as I ride. Well,
as I ride on my road bike... I had to put it on my road bike because I
didn't have a 31.8 FD, so I used an inner tube as a shim to fit the
34.whatever-mm clamp.

--
Phil, Squid-in-Training

Ronsonic wrote:
On 5 Oct 2004 00:21:09 -0700, (Vladimir)
wrote:

The problem : Bad shifting from middle to little front ring under
load. I checked this at home: applied rear brake, shifted from middle
to little, pressed the pedal and saw as the chain bent the frame of
the derailleur about 2 mm outward. When I press the outer plate from
inside outward with my finger at the place wher the chain should be,
the whole frame first bends and only after that starts to rotate.
Front derailleur Deore 2003, installed 2 mm above big ring as manual
suggests. In my opinion the frame should not bend at all before it
starts to rotate under load. Am I right? The question is - are more
expensive models more rigid? Is there any table with exact figures
of rigidity of various front derailleurs? Maybe some tests performed
by some bicycle magazine? I would prefer heavier but more rigid.

Or how about not shifting under load?

Or am I just being old-fashioned and don't know how bikes work
nowadays?

No... this is a technique that all should learn. Shifting to a larger
chainring is less of an issue because one can use finger pressure to force
the shift.

Deores will wear out rapidly, however. My 1-season Deore has sloppy pivots,
and I rarely shift... the whole thing rattles like crazy as I ride. Well,
as I ride on my road bike... I had to put it on my road bike because I
didn't have a 31.8 FD, so I used an inner tube as a shim to fit the
34.whatever-mm clamp.

--
Phil, Squid-in-Training

Ronsonic wrote in message . ..

Or how about not shifting under load?

Yes, I know, one should not shift under load. To be exact there is
some rate of load, when no one can succesfully shift. The question is
- is this rate of load the same for any front derailleur? And the
second - should the derailleur's frame bend under load before its
spring yelds to this load?

I'm not _really_ trying to be a smart ass.

What did you say? I am not native english speaking, you know :-)

Ronsonic wrote in message . ..

Or how about not shifting under load?

Yes, I know, one should not shift under load. To be exact there is
some rate of load, when no one can succesfully shift. The question is
- is this rate of load the same for any front derailleur? And the
second - should the derailleur's frame bend under load before its
spring yelds to this load?

I'm not _really_ trying to be a smart ass.

What did you say? I am not native english speaking, you know :-)

"Phil, Squid-in-Training" wrote in message ...

Deores will wear out rapidly, however. My 1-season Deore has sloppy pivots,
and I rarely shift...

How does a deraileur pivot wear with no (or little) shifting?