It is important to check your bike each time you ride it to save you time in the end in case anything goes wrong.
1. Tires and wheels
You must always check to make sure your tires are properly inflated. Also make sure your wheels are very tight so that you wont go flying over the handle bars.
Squeeze your brake levers to make sure that apply enough pressure to stop your bike.
3. Seat post and handle bar stem
Make sure that your handle bar is tight and at the correct height, also make sure that your seat is adjusted correctly.
Check that the straps are adjusted so that the helmet fits snugly, and sits down on your forehead, hitting somewhere above your eyebrows.
5. Chain and gears
When you first set off check that your chain turns cleanly through your front and rear sprockets. Run your bike through its range of gears to make sure there are no problems with rough shifting.