Is a Shimano indexed shifter compatible with a non-indexed rd?
Iím setting up an 83 Schwann Letour Luxe as a townie for the bike library. I put some city bars on it and found a Shimano 6spd index/friction thumb shifter. My question isÖ is it possible to use the original pre-indexed 1983 Shimano Altus non-indexed r-derailleur with the shifter in indexed mode and have it effectively track a Shimano 6 spd freewheel.
Since all the parts are Shimano and from the same era, it should work. I did a similar conversion, except I used a Shimano grip shifter and a Sun Tour deraileur. The shifting isn't perfect, but my daughter hasn't complained about it yet.
I think mechanically the thing that would make the old Altus less than ideal for this application is the fact that it won't have the built-in "play" in the upper pulley that a made-for-indexing rear derailleur would have. This built-in "play" in the upper pulley is one of the key innovations that made indexed shifting finally work decently-