Honda Motorcycle VTX1800N headlight bulbs use 9003 size for both high and low beam functions. The replacement chart covers 2004 to 2008 production years with bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Honda Motorcycle VTX1800N uses the 9003 bulb size for both its high beam and low beam headlight positions across the 2004-2008 model years.
The 9003 is an ANSI-standard halogen bulb recognized in the United States and Canada, operating on a 12-volt system with a dual-filament design rated at 60 watts for high beam and 55 watts for low beam.
The dual-filament construction of the 9003 allows a single bulb to serve both the high beam and low beam functions, which is consistent with the VTX1800N sharing the same bulb specification across both headlight positions.
The 9003 uses a P43t base, a bayonet-style mount that physically determines fitment and is not interchangeable with bulbs carrying different base types, even when voltage and wattage ratings may otherwise appear similar.
The 9003 is the ANSI designation for what is internationally classified as the H4 bulb. These two designations refer to functionally equivalent bulbs, though labeling differences exist between North American and international markets.