Won a set of 6spd Campagnolo Syncro d/t shifters of the bay and was please. They arrived this afternoon and was doubly pleased.
Fitted them to the Pennine and was perplexed... I have no idea what rear mech I have but it worked perfectly with a set of Shimano 600 8spd shifters and a 7spd Campagnolo cassette.
I started to faff and scratch my head as minds were boggled by the combination of shifting, cassette and randomly purchased rear mech...
The answer was in the cassette spacing, 5mm for Campagnolo 8 and 4.8mm for Shimano - hence everything sort of worked for the bikes' previous owner.
I wasnt happy with the Shimpagnolo mix and had slowly replaced Japanese for Italian.
If you have Shimano d/t shifters and Campagnolo d/t shifters side by side, you'll notice that the Shimano barrel is bigger so it has a different cable pull compared to the Syncro:
I thought about it, ruined a few gear cables experiment with it but could not get the shifting right. Decided to take one issue out of the equation - make the cassette a 6 speed. All hail the Campagnolo cassette! plastic spacers and a Shimano tool compatible lockring... Joy.
Then looked at the shifting end - I needed to make the campag shifter the same or similar cable pull to the Shimano. How? Add a bit of cable outer from an old straddle cable, clamp the mech 'the other' way (cable on the outside of the clamp) and... And it worked! Nice indexed clicky shifting on the old Pennine.
A quick out and about and its road worthy again.