Message:
>What will work in place of a shimano sti 7 speed shifer without having to change out any additional parts?The cog spacing on 7-speed & 8-speed cassettes is essentially the same, so you can substitute almost any 8-speed shifter.
The general recommendation is to have the "extra" index click occur on the small end of the cassette -- this preludes the likelihood of the chain running off the cassette and into the spokes if the derailleur's stops go out of adjustment.