Honda Motorcycle CBX high beam and low beam headlight bulbs both utilize a 9003 bulb size. The replacement chart covers vehicle production spanning 1979 to 1982.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 9003 bulb is an ANSI-standard halogen type recognized in the United States and Canada, operating at 12 volts with a dual-filament design rated at 60 watts on the high beam filament and 55 watts on the low beam filament.
The P43t base is a bayonet-style fitting with a 43mm collar, which physically locks the bulb into the housing and ensures correct alignment of the filaments relative to the reflector.
The Honda Motorcycle CBX uses the 9003 bulb for both the high beam and low beam headlight positions across the 1979-1982 model years.
Because both beam positions share the same 9003 specification, a single dual-filament bulb serves the full headlight function rather than requiring two separate single-filament units.
The 9003 bulb is also marketed under the designation HB2 in some international contexts, though the ANSI 9003 designation applies specifically to the North American standard referenced in these specifications.
The dual-filament construction means the high and low beam outputs originate from within one glass envelope, and a failure of one filament does not necessarily affect the other, though the entire bulb requires replacement as a single unit.
The P43t base is not interchangeable with other common halogen base types such as H4, despite the H4 bulb sharing a similar wattage rating and dual-filament design, as the physical base configurations differ.