I got a second flat on a bike ride a few years ago. First flat was on the rear, second flat on the front. I only carry one spare tube and a patch kit. It was only 5 miles home and I was too tired to patch the second flat on the front. So there is a park next to a bike path that got me 95% of the way home, I rode the front flat on the grass beside the MUP all the way. It was easy and smooth, no damage at all to the rim or tire.