Hal's bicycle is resting near Huger, SC. Amazingly, none of us have suffered a single flat so far (I did have a problem with a tube in my front wheel in CT and I put in a new tube but that may have been a bad tube rather than a flat). We are all using Schwalbe touring tires which may account for the lack of flats. I checked the tread on my tires today and they seem to have a lot of tread left even though we have ridden over 2000 miles so far.