Using Continental el cheapo tires. 700x28. Get lots of miles out of them and few punctures. Should have 6000 miles out of this set. Of course they do get rotated twice during their useful lifetime. Have a pair of Conti City Ride tires that have never gone flat. Nope, neither tire rides particularly well such as a 220tpi tire, but I am 235 pounds and can make any tire flex enough to be satisfactory!