Aero <[email hidden]> 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