Got a flat tire on the way to High Noon and wrestled with it for 10 minutes before it immediately went flat again. Met the High Noon riders at the top of the Esplanade, and there was a lot of encouragement to try to fix it again. However, I hadn't been able to find the sharp object the first time around and didn't have confidence that spending more time on it would yield success. I really appreciated everyone's positivity, but I was happy to punt today and call for a ride. On the plus side, though, I met a fellow in a wheelchair at the west end of the Convention Center sidewalk who was having trouble getting up the hill along Holladay Street. We had a nice conversation as I helped to push him up to his bus stop on Grand Ave. Overall, I'm glad that I had this opportunity to be of assistance. At my pickup spot near the Kaiser Permanente office, I saw PBOT's bike lane sweeper in action.