We tour on our tandem, 286 lb. team + 44 lbs. gear. We run 28mm tires. I suggest that whatever type and width you decide on, that you look for a tire which has some sort of bead-to-bead flat protection. Touring, one sometimes encounters some nasty bits of road and sidewall protection can be very nice. Doesn't have to mean a heavy tire. We're running Vittoria Rubino Pro Tech 28mm tires for winter and touring use. Try Amazon, as they're out of production. Very reliable tire and fast enough.
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