Suzuki Motorcycle TU250X Tail Light Bulb Size

The Suzuki Motorcycle TU250X tail light utilizes a P21/5W bulb size for the rear lighting component. Data for the specific bulb requirements covers the range from 2009 to 2019.

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
2012-2019	P21/5W
2009	P21/5W

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W

Other Locations

Additional Notes

The Suzuki Motorcycle TU250X uses the P21/5W bulb for its tail light across all listed model years from 2009-2019.
The P21/5W is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope. The 21W filament serves the brighter stop light function, while the 5W filament handles the lower-intensity running light function.
The P21/5W operates on a 12V electrical system, which is standard for motorcycles of this type.
This bulb uses a BAY15d bayonet base. The BAY15d designation indicates an offset pin configuration, where the two pins are positioned at different heights around the base. This asymmetric design prevents incorrect installation by ensuring the bulb can only be seated in one orientation.
The P21/5W is an ECE-rated bulb, a standard recognized across Europe and many international markets, indicating it meets regulated photometric and safety requirements for signalling applications.
Because the BAY15d base is offset, it is not interchangeable with the BA15d base, which shares a similar appearance but features pins at equal heights. Substituting a BA15d bulb into a BAY15d socket is not possible without modification.