BMW Motorcycle R1100S License Plate Bulb Size

The BMW Motorcycle R1100S license plate uses H6W and DE3423 bulb sizes for the lighting components. Data for the specific bulbs covers the period from 1998 through 2005.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2001-2005	H6W
1998-2000	DE3423

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Single-filament signalling bulb with BAX9s base. 12V, 6W.	H6W
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423

Other Locations

Additional Notes

The BMW Motorcycle R1100S uses two distinct bulb types across its model years for the license plate position: the H6W for 2001-2005 and the DE3423 for 1998-2000.
The H6W is an ECE-standard bulb, meaning it conforms to European and international regulations, and operates at 12 volts with a 6-watt output through a single filament.
The H6W uses a BAX9s base, which is an offset pin bayonet fitting. This base type is not universally interchangeable with standard bayonet or wedge bases, making socket compatibility a relevant consideration.
The DE3423 is an ANSI-standard festoon bulb, a format governed by North American specifications, operating at 12 volts with a 41mm length and end-cap contacts at both ends.
Festoon bulbs like the DE3423 make contact through their end caps rather than a side-mounted base, which means they are physically incompatible with the BAX9s socket used by the H6W.
The two bulb types are not interchangeable with each other due to differences in both base design and regulatory standard, meaning the correct bulb is determined strictly by the model year of the R1100S.
The shift from the DE3423 to the H6W between the 2000 and 2001 model years reflects a change in the bulb standard applied to the license plate position on the R1100S.