I've posted the same reply in several threads, but here goes again: I would NOT look into 1 person shelters unless I was walking and carrying all the gear in my back (where every kilogram counts), or the shelter was a hammock/bivy (most if not all of these are for one person).

But if you're riding and specifically want a tent, look for 2 person tents at minimum. The weight penalty is not a big issue on the bike IMO, and extra tent space is valuable for me. YMMV.

--J