Honda GL1800 2004 Owner's Manual page 24

Shows riding speed in miles (USA) or kilometers (Canada) per hour.
Shows engine speed in revolutions per minute (rpm).
Shows excessive engine rpm range (indicated from the beginning of the
tachometer red zone) in which operation may damage the engine. Do not let the
tachometer needle enter the red zone.
Flashes when either turn signal operates.
Lights when the reverse system is engaged.
speedometer
tachometer
tachometer red zone
turn signal indicator (amber)
reverse system indicator
Gauges & Indicators
Instruments & Controls
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