Honda Motorcycle VT1100T Shadow ACE Tour Turn Signal Bulb Size
The Honda Motorcycle VT1100T Shadow ACE Tour front turn signal requires a 1034 bulb size, while the rear turn signal uses a 1073 or P21W bulb size. The replacement chart covers 1998 to 2001 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 VT1100T Shadow ACE Tour uses two distinct bulb types across its front and rear turn signal positions, specifically the 1034 for the front and either the 1073 or P21W for the rear, depending on the model year.
The 1034 bulb 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 brightness levels within a single housing, a characteristic shared with the 1157 family of bulbs, of which the 1034 is a variant.
The front turn signal position on the VT1100T Shadow ACE Tour uses the 1034 bulb across all four model years covered, spanning 1998-2001.
The rear turn signal position does not use a single consistent bulb across all model years. The 1073 is specified for 1999 and 2001, while the P21W is specified for 1998 and 2000.
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 bulb family.
The P21W is an ECE-standard single-filament signalling bulb rated at 12V and 21W, also fitted with a BA15s bayonet base. Its ECE classification reflects a European and worldwide regulatory standard rather than the North American ANSI system used by the 1073.
Although the 1073 and P21W share the same BA15s bayonet base, their wattage ratings differ substantially, at 13W and 21W respectively. This difference means the two bulbs are not electrically interchangeable without potential effects on circuit load and turn signal flash rate.
The 1034 uses a BAY15d base, which is physically distinct from the BA15s base used by both rear turn signal bulbs. The BAY15d base features offset locating pins to prevent incorrect single-filament bulb insertion, making cross-position substitution between front and rear bulbs mechanically incompatible.