Fix a Flat
A man doesn't like to admit he's never changed a bike tire. But there's shame, and then there's hiking ten miles when you could be riding. Let us help you avoid both indignities.
Always carry a pump, tire levers, and at least one spare tubejust don't store the tube with sharp tools.
(a) Unseat one sidewall from the rim with a lever. Pry the tire up and skin the sidewall off the rim. Use plastic levers (or plastic-coated steel) so you won't dent or crack your rims.
(b) Remove the dead tube and whatever caused the puncture.
(c) Pump up your fresh tube enough that it holds its form and insert.
(d) Remount as much of the tire as you can by hand before levering the rest into place, which can be a Herculean feat with newer tires. Make sure the tube isn't pinched by the tire. Pump 'er up.