Originally Posted by demoncyclist
The indexing is in the shifter, not the derailleur, so there may not be a problem. The chainrings, cranks, and BB will be no problem, and the front derailleur should be fine too. You shouldn't have to replace the freewheel yet. I have an 89 Cannondale M400 with Suntour XC-M, and it still runs fine. I replace chains relatively often, since they will wear faster with an older drivetrain, but it still runs and shifts without any major hiccups. Just a note for the future- it may be more cost effective down the line to replace the whole bike, rather than part by part as things eventually reach the point of no return.
DEMON
dcyclist,
Suntour shifters had "slop" incorporated in them to allow for misadjusted der's due either to incompetence or riding time. Go ahead and try Suntour index shifters wiith shimaNo der's. you will see soon enough. Also it does happen that new chains skip on old cog whether freewheel or cassette, depends on usage and wear, but it does happen.