Honda Motorcycle CBR1000F front turn signal bulb size is 1034, while rear turn signal bulb size is P21W or 1073. The replacement chart covers 1987 to 1996 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Honda Motorcycle CBR1000F uses two distinct bulb types across its front and rear turn signal positions: the 1034 for all listed front turn signal years, and either the P21W or 1073 for the rear turn signal depending on the model year.
The 1034 bulb is an ANSI-standard dual-filament bulb rated at 12V and 21/5W, mounted on a BAY15d bayonet base. Its dual-filament design makes it a variant of the 1157 and technically capable of serving both a primary and secondary lighting function.
The P21W is an ECE-standard single-filament bulb rated at 12V and 21W, mounted on a BA15s bayonet base. Its ECE classification indicates it conforms to European and international signalling standards rather than North American ANSI specifications.
The 1073 is an ANSI-standard single-filament bulb rated at 12V and 13W, also mounted on a BA15s bayonet base. It is a lower-wattage variant of the 1156 and draws notably less power than the P21W despite sharing the same base type.
Because the 1034 uses a BAY15d base and the P21W and 1073 use a BA15s base, these bulb types are not interchangeable with one another. The offset pins of the BAY15d base physically prevent installation in a BA15s socket.
Although the P21W and 1073 share the same BA15s base, their wattage ratings differ significantly at 21W and 13W respectively. Substituting one for the other in the CBR1000F rear turn signal position may affect signal brightness and could conflict with the motorcycle's flasher relay calibration.
The Honda Motorcycle CBR1000F rear turn signal specification alternates between the P21W and the 1073 across different model years. The 1073 is specified for 1991 and 1995, while the P21W is specified for 1987, 1988, 1990, 1993, 1994, and 1996.
The front turn signal position uses the 1034 consistently across all listed years from 1987-1996, making it the only position on this model with a uniform bulb specification throughout the documented production span.
The 1034's dual-filament construction contrasts with the single-filament design of both rear turn signal bulbs. This distinction is relevant to socket wiring, as a BAY15d socket carries separate circuits for each filament, whereas a BA15s socket carries only one.
The ANSI and ECE standards represented in these specifications are not regionally interchangeable in a regulatory sense. The P21W's ECE classification and the 1034's and 1073's ANSI classifications reflect different testing and approval frameworks for automotive lighting components.