StephenH

I've mostly used 32mm Gatorskins on the tandem with fairly heavy wheels, but do have a set of lighter wheels with 28mm Gatorskins.
I would want something wider for gravel, but there's not much room inside the fork (radial dimension, not width) to go bigger.
Friends that ride gravel tandems have one set up with 650 wheels and fatter tires, but I don't know the details. They have a second tandem set up for road.