The 2001 Yamaha FZ1 rear brake light switch, which is activated by the brake pedal, is properly adjusted when the brake light comes on just before takes effect. If necessary, adjust the brake light switch as follows:
Turn the adjusting nut while holding the rear brake light switch in place. To make the brake light come on earlier, turn the adjusting nut in direction a. To make the brake light come on later, turn the adjusting nut in direction b.
Legend: 1. Rear Brake Light Switch; 2. Rear Brake Light Switch Adjusting Nut