Inspection Before the Ride
Before you get on your bike to take a ride, particularly a long ride, it's important to give a quick look to check that all bike parts are tight, well adjusted, and working properly. Assuming you don't find any problems, this inspection should take no more than a few minutes. Any problems you find, though, should be tended to immediately. The following is a discussion of things to check.
Check the frame. Most frames are strong enough to easily handle normal riding. But, if you have a mountain bike and take it off-road a lot, you should check the frame closely for cracks and dents before (and after) you take it out on the trails.
Check quick-releases. Depending on your bike, you may have quick-release levers on the seat tube or front and back wheel hub. Make sure these are locked and secured tightly.
Check seat. Seat tilt should be in the correct position and fastened tightly. It can come loose from hard riding, particularly off-road.
Check tires. Tires should be properly inflated to the recommended pressure, which is usually written on the side of each tire. Use a tire gauge to measure the air pressure. If necessary, inflate the tires with an air pump. Also, check the surface of the tires for worn-down tread or cuts.
Check wheels. Spin each wheel to see that it is properly centered in the frame and completely flat (called true). If the wheels look wobbly when they spin, they may need to be trued (or the hub bearings may need adjustment). Also, try to move the wheels side to side with your hand to make sure that they are secure and don't touch the brake pads. In addition, make sure the spokes are tight by moderately plucking them.
Check brakes. Squeeze each brake lever independently as you push the bike forward. The levers should activate the brake pads to press securely around the wheel rim and stop the wheels completely. Check that the pads are not worn down and also make sure the rims are clean and dent free.
Check the cables. Inspect the entire length of brake and derailleur cables for any breaks or loosening, particularly at the mounting points.
Check the crankset. Both the pedal screws and the chainwheel bolts tend to come loose over time. Feel for play in these areas.
Check the headset and forks. The headset should be sturdy and tight, but turn smoothly. Make sure headset bearings do not rattle. If you have a mountain bike with suspension forks, check that all fork bolts are secure. Push down on the handlebars to test whether the suspension works properly.