Originally Posted by noglider

I renovated the drivetrain on my tandem. I replaced the rear hub, rear derailleur, cassette, and rear shifter, going from 7 speed to 11 speed. I had a triple chainring crankset. The Deore XT 11 speed shifter (made for flat bars) might be the best shifter of any type I've ever used because it's fast and accurate. I didn't change the front derailleur or shifter. It happened that the narrower chain fell between chainrings so I had to get a new rear crankset. I replaced only the right crank (and chainrings) and found one made for 10 speed. The left shifter is an old ratchet friction style, not indexed, and it works fine.