out of saddle shifting

[Dw]

when climbing out of the saddle, I find chain shifting to a
smaller rear cog without input from the campy ergo shifter;
pull it back up, and it stays put for seated pedaling, but
slips back when I stand up; any thoughts?

 

[Per ElmsäTer]

dw wrote:
> when climbing out of the saddle, I find chain shifting to
> a smaller rear cog without input from the campy ergo
> shifter; pull it back up, and it stays put for seated
> pedaling, but slips back when I stand up; any thoughts?

Flexing frame, especially around the BB area.
--
Perre

You have to be smarter than a robot to reply.

 

[daveornee]

Originally posted by Dw
when climbing out of the saddle, I find chain shifting to a
smaller rear cog without input from the campy ergo shifter;
pull it back up, and it stays put for seated pedaling, but
slips back when I stand up; any thoughts?

Check the "autoshifting" article on Sheldon Brown's site:

<http://sheldonbrown.com/autoshift.html>

Sometimes fixed by cleaning the area & cable under the Bottom Bracket guide and/or applying a bit of grease on the cable where it passes through the guide.

As indexing distances become closer the problem is magnified. Strong riders and/or flexible frames also magnify this.

 

[Harris]

dw <[email protected]> wrote:
> when climbing out of the saddle, I find chain shifting to
> a smaller rear cog without input from the campy ergo
> shifter; pull it back up, and it stays put for seated
> pedaling, but slips back when I stand up; any thoughts?

Classic case of autoshifting. See:

http://www.sheldonbrown.com/derailer-
adjustment.html#autoshift

Art Harris

 

[Richard Adams]

"Per Elmsäter" <[email protected]> wrote in message news:<[email protected]>...
> dw wrote:
> > when climbing out of the saddle, I find chain shifting
> > to a smaller rear cog without input from the campy ergo
> > shifter; pull it back up, and it stays put for seated
> > pedaling, but slips back when I stand up; any thoughts?
>
> Flexing frame, especially around the BB area.

Man, that's a lot of flex.

Original poster: What bike/frame are you using, 8/9 or 10
speed?

 

[Steve]

It can happen.......

I saw Ken Carpenter (6'6" 240 World class trackie racer) go
down hard in front of me when he was out of the saddle
sprinting on a 60+ cm ti bike

On 6/3/04 4:20 PM, in article
[email protected], "Richard
Adams" <[email protected]> wrote:

> "Per Elmsäter" <[email protected]> wrote in message
> news:<[email protected]>...
>> dw wrote:
>>> when climbing out of the saddle, I find chain shifting
>>> to a smaller rear cog without input from the campy ergo
>>> shifter; pull it back up, and it stays put for seated
>>> pedaling, but slips back when I stand up; any thoughts?
>>
>> Flexing frame, especially around the BB area.
>
> Man, that's a lot of flex.
>
> Original poster: What bike/frame are you using, 8/9 or
> 10 speed?

 

[Qui Si Parla Ca]

dvwlt-<< when climbing out of the saddle, I find chain
shifting to a smaller rear cog without input from the campy
ergo shifter; pull it back up, and it stays put for seated
pedaling, but slips back when I stand up; any thoughts?
>><BR><BR>

Perhaps the flex of the frameset is stronger than the right
ergo shift spring. In other words, perhaps you need a right
ergo OVH, with new shift springs.

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

 

[Dw]

[email protected] (Qui si parla Campagnolo ) wrote in message news:<[email protected]>...
> dvwlt-<< when climbing out of the saddle, I find chain
> shifting to a smaller rear cog without input from the
> campy ergo shifter; pull it back up, and it stays put for
> seated pedaling, but slips back when I stand up; any
> thoughts? >><BR><BR>
>
> Perhaps the flex of the frameset is stronger than the
> right ergo shift spring. In other words, perhaps you need
> a right ergo OVH, with new shift springs.
>
> Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St.
> Boulder, CO, 80302
> (303)440-3535 http://www.vecchios.com "Ruote convenzionali
> costruite eccezionalmente bene"

Yes, I think this is right, and may be related to the fact
that the sound of the right shifter recently went form an
audible click to basically silent operation when changing to
a bigger rear cog. Wondering whether the overhaul is hard to
do, and what parts you would expect to need. Also, existing
is '96 Chorus -- is it critical to match this?