BMW Motorcycle K100RT Brake Bulb Size

The BMW Motorcycle K100RT brake light requires a P21W bulb size for proper operation and visibility. Data for the specified component covers the period from 1985 through 1988.

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

YearsBulb Size
1985-1988P21W

Bulb Specifications

Description Bulb Size
ECE standard (Europe & worldwide). Single-filament signalling bulb with BA15s bayonet base. 12V, 21W.P21W

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