The Ducati 748 Biposto headlight bulb specifications include an H1 size for high beam and H3 size for low beam applications. The replacement chart covers 1997 to 1999 production years with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Ducati 748 Biposto uses the H1 bulb for the high beam headlight across the 1997-1999 model years.
The H1 is a single-filament halogen bulb operating on a two-pin base, designed for dedicated high beam applications where a separate bulb handles each lighting function.
The low beam headlight on the 748 Biposto is fitted with the H3 bulb across the same 1997-1999 span.
The H3 is also a single-filament halogen bulb, distinguished by its single central wire connector rather than a pin base, and is commonly used in fog and low beam positions on motorcycles and automobiles.
Because the H1 and H3 use different base configurations, the two bulb types are not interchangeable with each other, and installing the incorrect type in either housing is not possible without modification.
The consistent use of H1 and H3 across all three listed model years indicates that the headlight housing design remained unchanged on the 748 Biposto throughout the 1997-1999 production period.