Motorcycle turn signals

The installation of resistors when changing indicators will depend on 2 parameters:

- The power of the original indicator

- The power of the adaptable indicator to be fitted

The difference in power will be compensated by the resistor so that the new indicator works optimally.

Ex: Let's take an indicator with an original bulb developing 21W and a LIGHTER sequential LED indicator ref IN1126.

The difference in power to be made up is 21W - 2.4W = 18.6W per indicator.

With the engine running, the alternator delivers a voltage of approximately 13.5V.

Here we are looking for the resistance to compensate for the power of 18.6W

The formula used according to Ohm's law is R (resistance) = V (voltage)²/P (power).

This gives us R=V²/P=13.5²/18.6=9.80 Ω

So it will be enough to mount a 10 Ω resistor (ref IN820) on each flasher to have the correct operation.