I decided that I would try SIS shifting on my older Road Bike.
I replaced the 6 speed FW with a 7 speed FW 12-28, got a set of downtube 7 speed shimano SIS shifters on E-bay. I took a fairly new SORA derailer off of another bike (the Sora was not rated for a 32 tooth FW anyway)
I can get the low to high shifting to work fine but cannot get the high to low to index properly. It takes two clicks to get off the 28T. If I adjust for high to low it wont shift up on the first click and clatters.
The Chain is the same one. The 6 speed suntour had a 28 tooth high gear.
'''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Could be the chain if you have an old, wide 6-speed chain but it also could be that the rear derailleur limit screws aren't adjusted properly. Adjust them with the rd cable disconnected, then set up the shifting.
I will double check the Cable. I will probably just replace it tonight.
The Chain is an older style six speed chain. I will be at the bike shop so I will also get a chain
I have searched for some kind of a Chain Chart showing the different dimensions but come up empty.
Is 7 & 8 speed chain different? I assume so
How about 6-7 speed chain. I suspect they are but am wary of labeling for marketing purposes and some of the LBS guys dont always know slightly older technology