Wiring accessories on motorcycle

tamarillo, Apr 19, 9:19pm
I have a bike specific twin air horn already using a relay and a fused wire from battery.
Now I have heated grip and a heated vest to add.
Rather than run more wires I'm thinking of one good thick wire from battery.
Take first live off it for the vest before it goes under tank, then run both vest and grips from the wire after its gone under tank.
What wire? What grade wire do I need to carry it. Grip and vest will likey be on together and don't want to blow something using horn!
Thanks in advance.

motorboy2011, Apr 19, 10:18pm
I'd be fitting a amp meter 1st, bikes don't tend to have a lot of extra when it comes to power if the lights are on + break light + indicators.

bwg11, Apr 19, 10:50pm
Get the current draw from the specs of the grips and vest, there are plenty of on-line calculators to give you wire size needed taking into account the length of the run. Description of sizes can be confusing as several conventions exist. Run a feed straight from the battery with an in-line fuse close to the battery.

The air horns will require a relay, again powered directly from the battery via another in-line fuse. The relay will be triggered by your existing horn circuit.

clark20, Apr 20, 12:06am
Don't forget the fuse first close to the battery. I like to use 0.1mm2 per amp, so 1.1mm2 cable will carry 11 amps (or 130 Watts)

tamarillo, Mar 4, 7:16pm
Yep air horns already in with relay as per manufacturers instructions.
Good idea re working out draw and going online, will do.
Bike can handle them, in colder climes they run heated trousers, socks, gloves the works on them. They're designed to be low draw.
Thanks.