Installing a 12v Power Strip
As an Iron Butt rider, I tend to have a whole host of electrical add-on goodies on my bikes.... aux lights, heated clothing, radar/GPS, etc, etc. There are many different approaches to installing a (fused and relayed) power source on a motorcycle in order to provide power for all your electrical farkles. I've used the following approach with great success on all my bikes.
First it's off to Rat Shack to score the basic components: a 8-terminal Barrier Strip and attending 8-terminal "jumper", a heavy-duty 30-amp 12v relay, and an inline fuse holder, as follows:
The basic steps:
Use a premium 12-gauge wire with a ring terminal directly off the battery's positive post to feed a high-quality, heavy-duty, 4 or 5 terminal 12v relay. Insert a heavy-duty fuse holder (ensuring it uses the same type of 12-gauge wires also) as close to the battery as practical. Use a 25-amp fuse. The other end of this wire plugs into the number 30 terminal of your relay.
The other terminals of your 4-terminal relay are typically numbered "85", "86", "87". As mentioned above, relay terminal "30" receives the hot wire directly from the battery; terminal 87 will be the hot wire out of the relay to power your power strip/fuse bar/whatever. This is your "hot" circuit once the relay is activated by the ignition switch.
Terminals 85 and 86 are used to activate the relay and allow power to flow out of terminal 87 towards your barrier strip/fuse block. Connect terminal 85 to any good grounding point. Connect terminal 86 to any circuit that is "hot" with the ignition is turned on, such as one of the two front turn signals. For terminal 85/86, you don't need heavy 12-gauge wire, the typical automotive 16-18 gauge wire is more than sufficient for this task.
There are excellent relay mounting opportunities under the cowling, and plenty of room, too, even on the ABS models.
|Dual-Row Barrier Strips-8 Position
Catalog #: 274-670
Catalog #: 274-650
|30-amp, 12vdc Relay
$5.99 Brand: RadioShack
Catalog #: 275-226 Model: 275-226
|Inline Mini "Blade" Fuse Holder |
$2.49 Brand: RadioShack
Catalog #: 270-1237
Below you are looking at two relays I mounted using two stock fasteners near the left mirror attach points. Relay 'A' provides power to the Barrier Strip. Relay 'B' is a relay specific to my Widder connectors. Item 'C' is the very important heat-resistant wire loom from NAPA, p/n 737101, costs $1.99 per foot, and is most definitely The Shit when it comes to protecting 12v positive circuits from the heat of the engine bay. This wire loom (it's referred to as "asphalt loom"; why, I don't know) protects wire up to 250 degrees F.
Item 'D' is simply the two mirror mount studs highlighted just to orient you on where we are here under the cowling.
I personally recommend that you use these same fasteners that reside on the right side of the nose cowling, vice the left side you see below. Placement on the right side means you're right next to the battery, and thus don't have to string a wire across the cowling like I have done here (in my case, I had to go this route because that massively huge PIAA relay assembly resides where I would normally mount the relays):
It was my hope to simply zip-tie the Barrier Strip oriented as you see in this photo below, which would allow me to still get a phillips-head screwdriver in there for future farkling, but it was not to be. Placement of the barrier strip here interferes with re-installing the cockpit dash panels. I ended up having to rotate the barrier strip such that the screws all point directly to the ground. Thus in the future, when I go to add another electrical goody, I'll have to snip off the zip-ties to rotate the barrier strip so I can access the terminals, and use two fresh zip-ties to re-install.... no big deal.Note yellow arrow on the "asphalt" wire loom, which contains the hot lead coming directly off the battery:
I'm pretty happy with this farkle because mounting the barrier strip up in the nose means I didn't have to run a big-ass 12-gauge wire from the battery and through the hot engine bay (which is the case when locating your power strip under your seat, for example). After installing the Magnum Blaster trumpet horns and the Widder connectors, I still have five more available terminals that I can use for anything needing a switched power source.