Most bike accidents are due to equipment failure, weather conditions, and biker carelessness. To begin with, many different pieces of bicycle equipment can become defective and cause bike accidents. For example, if a bike does not have good brakes, it cannot be stopped effectively. Similarly, a weak light will make it more difficult for a biker tosee at night. Aside from defective equipment, a biker often has difficulty controlling his bicycle when it is windy and rainy. Under such conditions, water may impair the brakes and obstruct the biker's view; too much wind will affect steering. Nonetheless, bike accidents are mainly caused by biker who does not stop sign and by a biker whose pants' legs get caught in the bike chain. The number of bike accidents could be greatly reduced if bikers checked their equipment, rode in good weather, and practiced bike safety.