Honda Motorcycle CB1000 front turn signal bulbs use 1034 size while rear turn signal bulbs use 1073 or P21W size. The replacement chart covers 1994 to 1995 vehicle production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Honda Motorcycle CB1000 uses three distinct bulb types across its front and rear turn signal positions for the 1994-1995 model years: the 1034, 1073, and P21W.
The 1034 is an ANSI-standard dual-filament bulb rated at 12V and 21/5W, fitted with a BAY15d bayonet base. Its dual-filament design means it serves two lighting functions within a single housing, a characteristic it shares with the 1157, of which it is a variant.
The 1073 is an ANSI-standard single-filament bulb rated at 12V and 13W, fitted with a BA15s bayonet base. It is a lower-wattage variant of the 1156 and is intended for single-function signalling use.
The P21W follows the ECE standard rather than the ANSI standard, placing it in a different regulatory category from the 1034 and 1073. It is rated at 12V and 21W and also uses a BA15s bayonet base.
Although the 1073 and P21W share the same BA15s bayonet base, their wattage ratings differ significantly, at 13W and 21W respectively. This electrical difference makes them non-interchangeable despite their physical base compatibility.
The 1034 uses a BAY15d base, which is physically distinct from the BA15s base used by both the 1073 and P21W. The BAY15d base features offset locating pins to prevent incorrect single-filament bulb insertion, so cross-substitution between the front and rear positions is not possible.
The Honda Motorcycle CB1000 front turn signal position uses the 1034 for both 1994 and 1995, indicating a consistent fitment across those two model years for that position.
The rear turn signal position changed between model years. The 1994 CB1000 uses the P21W, an ECE-standard bulb, while the 1995 model uses the 1073, an ANSI-standard bulb. These two bulbs are governed by different international standards despite sharing the same base type.
The ANSI standard applies to the US and Canadian markets, while the ECE standard applies to European and worldwide markets. The presence of a P21W in the 1994 rear position suggests a market-specific fitment distinction for that year.
All three bulb types across both model years operate on a 12V electrical system, consistent with standard automotive and motorcycle electrical architecture.