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Motorcycle LED Tail Lights

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Lunar Accents design is currently manufacturing a rear custom motorcycle LED tail lights accessory designed specifically for a popular street bike. Cycra Racing ( located out of Hebron Ohio specializes in custom high quality plastics for motorcycles. Cycra Racing manufactures the custom motorcycle LED tail lights housing designed specifically for this custom LED lighting product. Working together, Lunar Accents and Cycra created these amazingly low profile LED motorcycle tail lights for one of the world's most popular motorcycle manufactures. Over the past several years, Lunar Accents has performed the critical role of light emitting diodes, wire, and component assembly, onto the taillight circuit board. Each LED motorcycle taillight board contains 56 surface mount components and three wire termination leads. Assembled custom motorcycle LED tail lights ship directly to Cycra Racing for final assembly into the custom taillight housing. After final assembly is complete, the LED taillights ship directly to the motorcycle manufacture.

custom motorcycle LED tail lights

Custom Motorcycle LED Tail Lights

The custom motorcycle LED tail lights measure 10.5 inches long by 0.5 inch wide, and contains 36 surface mount LED lights. Overall thickness measures only 0.125 of an inch. The "1210 package" light emitting diodes are evenly spaced at exactly 0.300 inche apart. The LED lights feature a domed lens that produces a narrow beam angle, ideal for taillight applications where intensity is critical. LED intensity rating is approximately 800 mcd while in brake light mode. While operating in brake light mode, the LED taillight appears extremely intense! The unit connects directly to the motorcycle's brake and marker light output wires, and operates directly from the 12-volt electrical system (14.0 volts while in operation). The integrated dual intensity feature produces a steady illuminated LED marker light until the brakes are applied. When the rider applies brakes, all LEDs will simultaneously double their intensity. This feature allows all 36 LED lights to operate in both modes of operation, as opposed to other LED lighting designs, with a configuration that might turn on only half the LEDs while in the LED marker mode.

LED Motorcycle Tail Lights

Nine individual LED circuits each contain four LEDs in series with two parallel current limiting resistors. A resistor network is ideal for this application for numerous reasons. A constant current configuration remains standard for automotive lighting applications, but is simply not necessary for this specific circuit design. The primary disadvantage of not utilizing a constant current system is potential of varying LED intensity as the source voltage changes. However, uniform intensity was not a critical in this application mainly because the LED motorcycle tail lights remain unused while the motorcycle engine is off. Rather than designating only a single resistor per LED light, the taillight utilizes two resistors in parallel. This unique design is what enables the dual intensity, marker light / brake light modes. When the brakes are applied, current passes through both resistors creating a reduced overall resistance. This causes the LED current and luminous output to increase. Two resistors in parallel will always create a combined resistance that is less than the value of the lowest valued resistor. This law of physics is what allows the parallel resistor network to function so perfectly in the LED taillight application. The LED taillight circuitry also contains two Zener diodes to protect against reversed polarity grounding. This protection is required because both brake and taillight circuits share a common anode of the first LED within each series circuit. Without the Zeners, the marker light circuit will ground through the motorcycle's brake light power lead any time the brakes are not applied. This undesired grounding would also apply to the brake light circuit, when the marker lights are off.