The Triumph Street Triple high beam and low beam headlight bulbs both utilize a 9003 size. Replacement bulb specifications for the Street Triple span from 2008 to 2018 in the chart.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Triumph Street Triple uses the 9003 bulb size across all listed model years (2008-2018) for both high beam and low beam headlight positions.
The 9003 is an ANSI-standard bulb designation recognized in the United States and Canada, making it a widely available halogen type in North American markets.
As a dual-filament bulb, the 9003 serves both beam functions within a single unit, which is why the Street Triple shares the same bulb size for its high and low beam positions.
The 9003 operates on a 12-volt electrical system and carries a 60-watt rating for the high beam filament and a 55-watt rating for the low beam filament.
The 9003 uses a P43t base, a bayonet-style mount with a 43mm flange, which determines physical fitment into the headlight housing.
The 9003 bulb type is cross-compatible with the H4 designation used in international markets, as both share the same base and filament configuration, though labeling differs by region.
Because both beam positions on the Triumph Street Triple (2008-2018) call for the same 9003 bulb, only one bulb type is required for a full headlight replacement across both functions.