Pump it up
Low tire pressure can cause a flat. Proper inflation can protect your tire, even if you hit a pothole, according to Bike Authority's Sherman McKee. "The best defense a rider has is an air pump," he says. "Pump your tires up every ride. These tires can lose air in just a week."
The last thing you want when you're taking a turn on a busy city street is your handlebars or seat twisting on their own. "Make sure everything is tightened down," advises Alex Nosse of Joy Machines Bike Shop. "Nothing should be swerving around. Everything should be fixed and bolted down firmly."
Gary Schumacher of Cain Park Bicycle recommends using Tri-Flow bicycle lubricant on your chain. "But it's good for other places, too," he says. Run the derailleurs [the mechanisms that allow your bike to shift in and out of gear] with Tri-Flow every three weeks when the weather's good." When the weather's bad, use it every time you ride.