This happened: my brother and I were out for a bike ride (mountain bike; single track) early this spring. It was the first day of open trails, so the place was packed. And it was my brother’s first time on a mountain bike, so we were going a little … um, slow. Dudes in latex gear on fancy bikes were passing us left and right, as if we were going in reverse. We felt a little like rookies, but we were still having fun.
Then a guy with tree-trunk-sized quads flies by us on a cross bike (y’know, skinny tires), and 20 seconds later we come across him stalled on the trail with a flat. He was getting ready to walk all the way back out to the trailhead (he had nothing on him), but I always carry a multi tool and patches in my pack, so I offered it up. He was super-grateful, and ten minutes later he went off he went to catch his buddies.
Later, when their group lapped us (yeah, I know), there were shout-outs and high fives all around for the rookies with the sense to bring a bike multi-tool and patch kit.
The moral is: every guy should own a multi-tool, and a few quick patches, and bring them along on every ride. You’ll never find a better way to make friends, get girls’ numbers, or generally just be a helpful person than having the tools to fix a bike in a pinch.
A good multi-tool (mine is the Park Tool Co. I-Beam Mini Fold-Up with Chain Tool) has a variety of hex wrenches, a screwdriver, a tire lever, and a chain tool. Obviously you can change a tire without a tire lever, but a dedicated lever makes things much easier and faster.
Throw in a tube patches kit and pump, and you’re golden, like a rolling bicycle repair shop. You may get lapped, but at least a flat tire or broken chain won’t stop you.