We had the same problem with the 28 panaracers that came on our Santana. a flat about every other week and finally separation of the front tire from the sidewall. 800 miles total . Both pinch flats and punctures as well as a glass cut that ruined the rear. We upgraded to continental gatorskins late in the season no further flats in the last 200 miles. They do not come larger than 28 but we were pleased with the ride. Nash bar has 28's if you have trouble getting them locally Be sure that you are airing the tires up sufficiently to prevent pinch flats. That was responsible for several of ours. We do 120 psi with only the glass cut since then . used to ride at 100 psi