Honda Motorcycle CBR900RR front turn signal bulbs measure 1034 in size, while rear turn signal bulbs measure P21W and 1073, with replacement specifications detailed in the accompanying chart. The chart covers vehicle production years spanning 1992 to 1999 and documents bulb size data across this range.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Honda Motorcycle CBR900RR uses two distinct bulb standards across its front and rear turn signal positions: the ANSI standard, common in the US and Canada, and the ECE standard, used in Europe and worldwide markets.
The 1034 bulb is specified for the front turn signal across all model years from 1992-1999 without variation. It is a dual-filament bulb operating at 12V with a 21/5W output and a BAY15d bayonet base.
The dual-filament design of the 1034 means it carries two separate filaments within a single bulb, typically serving two lighting functions simultaneously, such as turn signaling and running light duties.
The 1034 is classified as a variant of the 1157, sharing the same BAY15d base type. However, the two are not necessarily interchangeable, as wattage and filament ratings may differ between variants.
The rear turn signal position on the Honda Motorcycle CBR900RR uses either the P21W or the 1073 bulb depending on the model year, making the rear position the only one with specification variation across the production run.
The P21W is an ECE-standard single-filament bulb with a BA15s bayonet base, rated at 12V and 21W. It is specified for the rear turn signal in 1993-1994 and 1996-1999.
The 1073 is an ANSI-standard single-filament bulb also using a BA15s bayonet base, but rated at a lower 13W output. It is specified for the rear turn signal in 1992 and 1995.
Although the P21W and 1073 share the same BA15s base type, their wattage ratings differ at 21W and 13W respectively. This difference means the two bulbs are not interchangeable despite their physical base compatibility.
The front and rear turn signal positions use different base types. The front uses the BAY15d base found in the 1034, while the rear uses the BA15s base found in both the P21W and 1073. These base types are physically incompatible with each other.
All bulbs specified across both turn signal positions on the CBR900RR operate on a 12V electrical system.