Honda Motorcycle VT700C Shadow Turn Signal Bulb Size
Honda Motorcycle VT700C Shadow front turn signal bulbs measure 1034 in size, while rear turn signal bulbs measure P21W or 1073, with each bulb size corresponding to specific lighting positions on the motorcycle. The replacement chart covers 1983 to 1987 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 VT700C Shadow uses three distinct bulb types across its front and rear turn signal positions for the 1983-1987 model years: the 1034, the P21W, and the 1073.
The 1034 bulb is an ANSI-standard type rated at 12V and 21/5W, featuring a dual-filament design with a BAY15d bayonet base. It is classified as a variant of the 1157 and applies to the North American and Canadian markets.
The P21W is an ECE-standard single-filament signalling bulb rated at 12V and 21W, fitted with a BA15s bayonet base. Its ECE designation reflects use in European and worldwide market applications.
The 1073 is an ANSI-standard single-filament bulb rated at 12V and 13W, also using a BA15s bayonet base. It is a lower-wattage variant of the 1156 bulb.
The front turn signal position on the VT700C Shadow uses the 1034 bulb uniformly across all model years from 1983-1987.
The rear turn signal position shows variation across model years. The P21W is specified for 1983, 1986, and 1987, while the 1073 is specified for 1984 and 1985.
The 1034 and P21W are not interchangeable. The 1034 has a dual-filament construction and a BAY15d base, whereas the P21W is single-filament with a BA15s base. These base types are physically incompatible.
The P21W and 1073 share the same BA15s bayonet base type, but their wattage ratings differ significantly, at 21W and 13W respectively. This difference affects electrical load and light output, making them non-equivalent substitutes despite the shared base format.