Honda Motorcycle VT1300CT Interstate Turn Signal Bulb Size
Honda Motorcycle VT1300CT Interstate front turn signal bulbs measure P21/5W in size, while rear turn signal bulbs measure P21W, with each bulb type specified for its respective location. The replacement chart covers 2010 through 2015 model years and details bulb size specifications across the vehicle production range.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Honda Motorcycle VT1300CT Interstate uses two distinct bulb types across its front and rear turn signal positions for the 2010-2015 model years.
The front turn signal on the VT1300CT Interstate takes a P21/5W bulb across all six model years covered in the specifications.
The P21/5W is a dual-filament bulb rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base.
The BAY15d base features two offset pins, which physically prevents it from being inserted in the same orientation as a single-filament BA15s socket, making the front and rear bulbs non-interchangeable.
The rear turn signal on the VT1300CT Interstate takes a P21W bulb across all six model years covered in the specifications.
The P21W is a single-filament bulb rated at 12V at 21W, mounted on a BA15s bayonet base, which has two pins positioned symmetrically on opposite sides of the base.
Both the P21/5W and P21W conform to ECE standards, a regulatory framework recognized across Europe and numerous other markets worldwide.
Although both bulb types share a 21W primary filament rating, the differing base types, BAY15d for the P21/5W and BA15s for the P21W, mean the two bulbs are not physically interchangeable between front and rear positions.