STI Levers

Discussion in 'Cycling Equipment' started by Aero, Jun 30, 2003.

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  1. Aero

    Aero Guest

    I am trying to upgrade a 7-speed friction down tube shifter setup to Shimano STI levers. I can
    measure front and rear derailleur mechanical advantage and also rear cog spacing. Does anyone know
    where I can get specs on cable travel per click for a 7 or 8 speed Shimano STI shifter, so that the
    idexing will match my rear cog spacing and front chainring spacing. I tried the Simano Website. No
    luck. I haven't been able to find it at Sheldon Brown's site. Any suggestions?

    Thanks.

    aero
     
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  2. Aero <[email protected]> wrote:
    : I am trying to upgrade a 7-speed friction down tube shifter setup to Shimano STI levers. I can
    : measure front and rear derailleur mechanical advantage and also rear cog spacing. Does anyone know
    : where I can get specs on cable travel per click for a 7 or 8 speed Shimano STI shifter, so that
    : the idexing will match my rear cog spacing and front chainring spacing. I tried the Simano
    : Website. No luck. I haven't been able to find it at Sheldon Brown's site. Any suggestions?

    The only 7-speed STIs that I'm aware of are the RSX ones. So the options are limited there. If
    you want to go 8-speed then there are more choices but be wary of 8-speed Dura-Ace; the spacing
    is unique.

    Any STI regardless of 'speed' should also index modern derailleurs fine. I've used a 6-speed Shimano
    600 derailleur with an 8-speed cassette.

    If it helps any, in a jam I got by using my 8-speed STIs with a 6 speed cassette. It didn't index
    perfectly, but I was able to have some great training rides.

    I think the rule of thumb goes something like: 5, 6, 7 speeds have the same spacing while 8, 9 and
    10 have the same total cassette width but different inter-gear spacing.

    It really is pretty straight forward, but if you choose to mix and match too wildly then you're
    pretty much on your own.

    Cheerz, Lynzz
     
  3. Jack Fortune

    Jack Fortune Guest

    On Mon, 30 Jun 2003 17:24:10 -0400, "Aero" <[email protected]> wrote:
    > I am trying to upgrade a 7-speed friction down tube shifter setup to Shimano STI levers. I can
    > measure front and rear derailleur mechanical advantage and also rear cog spacing. Does anyone know
    > where I can get specs on cable travel per click for a 7 or 8 speed Shimano STI shifter, so that
    > the idexing will match my rear cog spacing and front chainring spacing. I tried the Simano
    > Website. No luck. I haven't been able to find it at Sheldon Brown's site. Any suggestions?
    >
    > Thanks.
    >
    >
    > aero
    >
    >

    What is you wish to accomplish? Are you simply looking for Shimano 7-speed STI shifters? The only
    model that is currently available (new) is the Shimano Sora. Practically any Shimano rear derailer -
    except for older Dura ace - will index correctly with this shifter.

    What may be more problematic is the front shifting. Many older chainrings without the ramps and pins
    don't work very well with STI shifters...

    Jack Fortune
     
  4. "Aero" <[email protected]> wrote in message news:[email protected]...
    > I am trying to upgrade a 7-speed friction down tube shifter setup to
    Shimano
    > STI levers. I can measure front and rear derailleur mechanical advantage and also rear cog
    > spacing. Does anyone know where I can get specs on
    cable
    > travel per click for a 7 or 8 speed Shimano STI shifter, so that the
    idexing
    > will match my rear cog spacing and front chainring spacing. I tried the Simano Website. No luck. I
    > haven't been able to find it at Sheldon
    Brown's
    > site. Any suggestions?
    >

    If your 7spd uses a Shimano Cassette, you can use any of the non-Dura Ace 8spd parts and just limit
    the travel of the derailleur via the adjustment screw, as 7 & 8spd cog spacing was the same. I ran
    8spd STI levers on my older 7spd Shimano bits quite a bit before finally upgrading the rest of the
    parts. Worked fine front and rear. No experience trying it non-Shimano cogsets, though.
     
  5. In article <[email protected]>, [email protected] says...
    >
    >
    >I am trying to upgrade a 7-speed friction down tube shifter setup to Shimano STI levers. I can
    >measure front and rear derailleur mechanical advantage and also rear cog spacing. Does anyone know
    >where I can get specs on cable travel per click for a 7 or 8 speed Shimano STI shifter, so that the
    >idexing will match my rear cog spacing and front chainring spacing. I tried the Simano Website. No
    >luck. I haven't been able to find it at Sheldon Brown's site. Any suggestions?

    Save yourself some hassle and just get any 8spd or newer derailleur. If your cassette, or freewheel,
    is SIS compatible, then you are set.
    -----------------
    Alex __O _-\<,_ (_)/ (_)
     
  6. In article <[email protected]>, [email protected] says...

    >The only 7-speed STIs that I'm aware of are the RSX ones. So the options are limited there. If
    >you want to go 8-speed then there are more choices but be wary of 8-speed Dura-Ace; the spacing
    >is unique.

    Spacing is not unique for DA, so any 8spd cassette will work. BUT, you have to have matching shifter
    and rear derailleur.
    -----------------
    Alex __O _-\<,_ (_)/ (_)
     
  7. Jack Fortune

    Jack Fortune Guest

    On Tue, 01 Jul 2003 16:28:38 -0400, Alex Rodriguez <[email protected]> wrote:
    > In article <[email protected]>, [email protected] says...
    >
    > >The only 7-speed STIs that I'm aware of are the RSX ones. So the options are limited there. If
    > >you want to go 8-speed then there are more choices but be wary of 8-speed Dura-Ace; the spacing
    > >is unique.
    >
    > Spacing is not unique for DA, so any 8spd cassette will work. BUT, you have to have matching
    > shifter and rear derailleur.
    > -----------------
    > Alex __O _-\<,_ (_)/ (_)
    >
    >

    Alex,

    An 8-speed cassette will not fit onto a 7-speed freehub. To use an 8-speed cassette, he would need
    to replace the freehub body, re-dish and respace the wheel.

    A 7-speed shifter with the current chain, derailer, & 7-speed cassette; or 8 of 9 cogs from a
    9-speed cassette with a 9-speed shifter & chain will work.

    There is no need to replace the rear derailer - any shimano rear derailer designed for indexing
    (except for early Dura-Ace) will work fine with 7, 8 or 9-speed setups.

    The bigger problem is going to be converting the *front* to use index shifting...

    Jack Fortune
     
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