The Suzuki Motorcycle GS550 uses a 9003 bulb size for both high beam and low beam headlight applications. The replacement chart covers vehicle production spanning 1979 to 1986 with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Suzuki Motorcycle GS550 uses the 9003 bulb size for both its high beam and low beam headlight positions across all listed model years from 1979-1986.
The 9003 is an ANSI-standardized halogen bulb recognized in the United States and Canada, operating on a 12-volt electrical system with a dual-filament design rated at 60 watts for high beam and 55 watts for low beam.
Because a single 9003 bulb serves both the high beam and low beam functions through its two filaments, one bulb handles the full headlight operation rather than requiring separate units for each function.
The 9003 bulb uses a P43t base, which is a bayonet-style mount with a 43mm collar. This base type determines physical fitment into the headlight housing and is not interchangeable with other base configurations.
The 9003 and H4 bulb types share the same P43t base and dual-filament halogen construction, making them functionally equivalent in many applications. However, fitment should be confirmed against the housing before substitution.