Subject: Re: shimano sti 7 speed shifter Posted by: Al on December 08, 2004 at 07:35:08: In Reply to: Re: shimano sti 7 speed shifter posted by Jim on December 07, 2004 at 20:44:49:

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. >> > Shimano 7 speed cog spacing is 5.omm and 8 is 4.8mm. Close enough it works for some,not for the more AR...FWIW, the chain will go off the big cog even with 7 speed if the limit screw is too loose. I put the extra click on the big cog side and set the limit screw correctly. The limit screws are not 'self adjusting'. Of course, in an ideal world, one does not have to substitute components from one group for another ... Since most of us are not living in an ideal world, and because most riders are not as fastidious about maintaining their equipment between rides as others, the advantage of having the extra click on the smallest cog is that IF there is any excess slack in the cable then it will more than likely be removed when the "first" shift is made. Of course, the cable's adjustment for the indexing must still be correct (READILY/easily adjusted!). "Self adjusting" derailleur stops -- yeah, I'm not sure that rear derailleurs actually go out of adjustment; so, although I have no personal experience with those spoke protectors, I have to presume there is a reason for them. Regardless, the likelihood of shifting into the spokes is lessened if the extra shift is after the smallest cog rather than the largest.