The KTM 400 Duke headlight bulb uses H1 size for both high beam and low beam applications. Replacement chart data covers 1994-1995 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 H1 is a single-filament halogen bulb operating at 12 volts and 55 watts, fitted with a P14.5s base. Single-filament construction means the bulb serves only one lighting function, so separate bulbs are required for high and low beam duties.
The KTM 400 Duke uses the H1 bulb for both the high beam and low beam headlight positions across the 1994-1995 model years.
Although both beam positions share the same H1 bulb type, they remain physically separate installations. The shared specification does not imply that a single bulb serves both functions simultaneously.
The H1 bulb conforms to ECE standards, a regulatory framework applied across Europe and numerous other markets worldwide. It also carries approval for use in the United States and Japan, reflecting broad international acceptance.
The P14.5s base is a single-pin design specific to the H1 bulb. This base type is not interchangeable with other common halogen bases such as H4 or H7, and substitution with physically incompatible bases is not supported by the specification.