Honda CBR1000ST 2019 Owner's Manual page 126

Emergency Stop Signal
Emergency stop signal activates when the
system detects hard braking about
50 km/h (31 mph) or above to alert drivers
behind you about sudden braking by rapidly
flashing both turn signal lights. This may help
to alert drivers behind you to take
appropriate means to avoid a possible
collision with your vehicle.
When the system activates:
122
Hard braking
Both turn signal indicators blink
The emergency stop signal stops operating
when:
You release the brakes.
●
The ABS is deactivated.
●
Your vehicle's decelerating speed
●
becomes moderate.
You press the hazard switch.
●
Brakelight come on
Both turn signals flash