Suzuki Motorcycle S50 Boulevard headlight bulbs use 9003 size for both high and low beam functions. The replacement chart covers 2005 through 2009 production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Suzuki Motorcycle S50 Boulevard uses the 9003 bulb size for both the high beam and low beam headlight positions across the 2005-2009 model years.
The 9003 is an ANSI-standard designation recognized in the United States and Canada, making it the North American equivalent of what is internationally classified as the H4 bulb type.
As a dual-filament halogen bulb, the 9003 houses two separate tungsten filaments within a single glass envelope, with one filament dedicated to the high beam function and the other to the low beam function.
The 9003 operates on a 12-volt electrical system and carries a wattage rating of 60W for the high beam filament and 55W for the low beam filament.
The P43t base is the standardized bayonet-style mount used by the 9003 bulb, and it governs physical fitment into the headlight housing.
Because both the high beam and low beam positions on the S50 Boulevard share the same 9003 specification, a single bulb type serves the entire headlight assembly rather than requiring separate bulbs for each function.
The shared 9003 fitment across both beam positions means a replacement bulb intended for the high beam position is not interchangeable with a bulb of a different type, as the low beam position requires the same P43t base and dual-filament configuration.