How come a cassette with shimano spacing works when your using Campag shifters?
It's to do with the amount of cable pull per click compared to how far the mech moves - just so happens that 10s Campag will index a Shimano 8s system (I think there are some useful snippets on the CTC's website about this, pretty sure - as you might expect - that Sheldon Brown compiled something for his site too). Likewise 9s Campag and 7s Shimano, which I have on my touring bike. This came about in my case because I like the look and action of Ergo levers, not a big fan of Shimano STI levers. On the other hand, Shimano-compatible cassettes and hubs seem easier and cheaper to source so I mixed and matched!
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