probably some no name chinese brand tire. The best and widest street style tire that I have found to be in the 29''/700c size is the Serfas Drifter. I bought mine at REI for ~$30 each. They're 2.0 or 2.1 inches wide and have an interesting pattern to them
I would recommend building one of these bikes to anybody though . I blew out the rear hub and haven't been able to find a replacement for it . As far as I know you cant even order from the manufacturer . Whoever that mat be .
just picked up a set of serfas drifters 29x2.0. im very happy with these tires. very comfy ride and they have pretty low rolling resistance.they seem to do good in the dirt too. thanks for everyones help.