25-01-19, 01:37 AM
I think a front indicator bulb is 21W so 20W for your two spot lights isn't much power and won't affect the battery. 20W/12V=1.7Amp so as long as your switch and wiring is rated higher than that you don't need a relay. But the question is how do you want to control the spot lights?
The easiest way would be add a new length of wire straight from the battery to a fuse, then to a switch on the handlebar, then to the spotlight, then to ground. That will work and is the easiest way to do it and has no connection to the bike's loom but doing it that way means the lights can be left on even when the keys are removed so if you forget to turn the lights off they will drain the battery.
The other way is to do it is to use any switched 12V that only comes on when the ignition is on to control a relay and power the lights through the relay. Or if you want the lights to come on when the low beams are on use the 12V low beam wire to control the relay. Using a switched 12V means that you can't leave the lights on and drain the battery and using the relay means the power for the lights doesn't go through the bike's wiring.
The easiest way would be add a new length of wire straight from the battery to a fuse, then to a switch on the handlebar, then to the spotlight, then to ground. That will work and is the easiest way to do it and has no connection to the bike's loom but doing it that way means the lights can be left on even when the keys are removed so if you forget to turn the lights off they will drain the battery.
The other way is to do it is to use any switched 12V that only comes on when the ignition is on to control a relay and power the lights through the relay. Or if you want the lights to come on when the low beams are on use the 12V low beam wire to control the relay. Using a switched 12V means that you can't leave the lights on and drain the battery and using the relay means the power for the lights doesn't go through the bike's wiring.