BMW Motorcycle R75/5 front and rear turn signal bulbs utilize P21W size specifications. The replacement chart covers 1969 to 1973 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 BMW Motorcycle R75/5 uses the P21W bulb type for both front and rear turn signals across all model years from 1969-1973.
The P21W is a single-filament bulb, meaning it serves one lighting function only, which suits dedicated turn signal applications where no combined stop or tail function is required.
The P21W operates at 12 volts and 21 watts, a wattage rating consistent with the higher visibility demands of signalling bulbs compared to lower-wattage position or tail bulbs.
The P21W uses a BA15s bayonet base, where "BA15s" denotes a single-contact bayonet fitting with a 15mm base width, distinguishing it from dual-contact variants such as the BA15d.
The P21W is an ECE-standard bulb, meaning it conforms to the United Nations Economic Commission for Europe regulations, reflecting the R75/5's European market origins.
Because the front and rear turn signal positions on the R75/5 share the same P21W specification, a single bulb type covers all four turn signal housings on the motorcycle.
The BA15s single-contact base is not interchangeable with the BA15d dual-contact base despite the identical 15mm pin spacing, as the contact configuration differs between the two.