Need help wiring a simple switch

The relay powered set up shown by Stosh is similar to what I have done on my 6th Gen.

Nowadays many motorcycle electrical accessories come pre-fitted with ring connectors which are presumably designed to be connected direct to the battery terminals. Overall I don't think that approach is a good idea, especially for any devices like a GPS which tend to require the voltage to be stepped down to 5 volts. This means the charging dock on a TomTom / Garmin motorcycle GPS will probably incorporate some sort of circuit board which will be constantly energised and will place a small but constant drain on your bike's battery even if the GPS is not attached.

Hence I wire most electrical devices via a relay which only goes live only when the bike is running. On my 6th gen I used a multimeter to locate the positive side feed going to the tail light and then tapped into that wire to use as the relay trigger wire 85 in Stosh's diagram. For the feed to terminal 30 - I took a wire direct from the battery positive (so no in-line fuse). Instead I installed a micro fuse box on the output side of the relay attached at terminal 87. That way each individual appliance is protected by its own suitably rated fuse - and a failure in any one should not affect all the other items, and provided you used some reasonably thick gauge wire on the feed to terminal 30 it makes it very easy to add other extras at a later date - so things like heated grips.

Otherwise Stosh's diagram is the way to go.

Hope that makes sense



SkiMad

 

Skimad's updated wiring diagram.

 

OK. More questions:

-I understand most of the diagram. The RD has a pos and neg wire. The positive connects to the power wire of the cig lighter socket, and the neg goes right to the neg battery terminal? Frame ground? Make a difference?
-which gauge wiring (all of it to/from the relay) should I use?
-micro fuse box. Never heard/seen one. Available at auto parts stores as well? I'm assuming it has a series of terminals in it to allow me to pick different size fuses for everything?
-I like this idea, but I also like the idea of not having to sit with the key on while I'll fiddling with the GPS on the side of the road. This seems the safer way to go though.
-So any other items I wanted to add to this in the future, I would just add/tap the new item's power wire to the wire that goes into #87, and run the new item neg to ground or the neg battery terminal as well?

PS Is Stosh on fire today or what?? Sick at home this week, Stosh? Another 12' of snow overnight keepin' you in today?

 

16 or 18 gauge wire would be your best bet. You don't want to go too thin as the thinner the wire, the more resistance to it, and the more heat it generates. Most of your lamps and such in the house is 16 gauge I think. That will take 120v @ 5 or so amps and be fine so that would be ample for your bike. House wiring is 14 for the most part, some 12 but it is solid and you want stranded wire.

 

Dont compare to house wiring! Not the same and in a very different system. Ac power has a duty- cycle of 50% (loose theory). This means that a smaller wire can carry more power before burning up. Dc systems are 100% duty.

Gauge size depends on load requirements and wire type. 21 strands of 32awg carries the same power as a wire of 40 strands of 38awg. But the first wire is a 16awg bundle and the second is an 18 awg bundle.

If total load is 10amps (9amps plus 10% and round up to nearest whole amp ) then you will need a 16awg wire of at least 12 strands that are 32 awg each. Such wire will carry 15 amps at 15v at 60 degrees Celsius without failing. (Some math not shown here to get to these numbers.)

Once you know how much current you need then we can give proper suggestions as to wire size.

As for bat neg or frame. Your choice, it doesnt really matter as they are connected to each other. Just make sure your main power is fused as close to the battery positive as possible. If that wire ever rubs through, that will protect you from a nasty bike fire.

Stosh: thanks for saving me the headache of looking those pics up. That is exactly what I described.

 

Zen biker's updated wiring diagram.

No probs my friend,happy to help if I can.

Gotta admit that after I drew up the pic of that wiring diagram above ZEN I stopped for a few minutes and stared at it. I had this odd nagging feeling that I'd seen that somewhere before but I just couldn't put my finger on where I saw it.
So I went downstairs and started rummaging through my parts boxes and sure enough last box on the bottom of the pile I found it. It's a plug-and-play accessory wiring harness that I bought years ago from Wire My Bike. I completely forgot that I had it.

Holy Smokes I think I mighta just had my first senior moment! :faint: :lol:

(spoken in low hushed tones) Shhhh..... Dude stop speaking the evil "S" word,it's mid April here in the Frozen Wastelands and it still just might. :heh:

LOL. Nah just killing some time while I'm waiting for some special transmission bearings that I ordered from Germany for my Ducati to arrive.

Here's a pic of what that wiring diagram above actually looks like in real life Greg.



To answer your questions,

The Orange wires (wire 30 in the diagram) are 12awg gauge wire.
The circuit protection fuse used in the inline fuse holder (Yellow arrow) is 30 amp.
The relay (Red arrow) is a 12 volt 4 pole 40 amp Normally Open relay.
The Red wire (wire 87 in the diagram) is 12awg gauge wire out to the butt connector (White arrow) and the four Red wires running from the butt connector to the mini fuse box (Green arrow) are all 14awg gauge wire.
The Purple wire (wire 85 in the diagram) is 14awg gauge wire.
The Green wire (wire 86 in the diagram) is 12awg gauge wire.


In case you were wondering Greg,the relay wire terminal numbers 85,86,87,and 30 are all clearly listed on the under side of the relay. No way to mess it up.

 

Are the wires just push & play into the back of the relay?

Oh! Any idea about this one?>>

-So any other items I wanted to add to this in the future, I would just add/tap the new item's power wire to the wire that goes into #87, and run the new item neg to ground or the neg battery terminal as well?

 

Yep.

You can either use individual female spade terminals to run each wire separately to it's own wire terminal post on the relay or there's also a fancy plug connector that you can get which holds all four wires together and makes for a much tidier routing.

Yep you could do that Greg however the mini fuse box as Skimad previously explained is really the way to go.

The mini fuse box has separate spade terminals for each "appliance" (Skimad's term to describe add-on devices,I like it so I'm running with it.) that you intend to use. There's no screwing around rewiring the #87 terminal wire every time that you want to add another appliance.

With the mini fuse box you simply slide your power wire onto one of the unused wire terminals on the fuse box,install your fuse,and connect the ground wire for that appliance to either the frame ground or the battery negative terminal and badda-bing-badda-boom you're good to go. Doesn't get any more plug-and-play than that. :drum:

 

Mini fuse boxes sold @ Pep Boys, etc just like the relay? I have never seen them before.

 

This is the current system that I'm going to install on my 03. I don't need 6 circuits at this point and probably never will use more that 3 or 4 of them. However this was the best of both worlds in that it provides not only 6 fused power slots but also a ground bus so that I have all of my wiring located in one central location. which will be behind the airbox and battery on the Rt. side of the bike. The Voltmeter and Cig socket is going to take some thought as the location I had originally slated it for had allot of potential for interfering with the bars at full lock. I'm still waiting on the fusbox and relays to arrive and will post up a How-To once they get here.

 

Trying to do a quick routing/test on this today while my parts come in on this.

I've spent a good bit of time today with a test light, trying to find a hot/power wire that's in/on/around the taillight that is hot only when the key is on. Tried all 3 wires leading into the taillight bulb itself, and a myriad of others.

Each one I've hit is hot (and lights my test light) when the key is off.
Anyone got any tips on either what color wire might be hot with the key on, or maybe where to find it?

 

Well, you sure are close. And i'd just suggest you repeat the voltage test.
Of the three wires going to the light switch, one is a ground and one is the brake light. Neither are hot with the power on. The ground is usually green. It will show on the wiring diagram.
The other one is the running light. It should show ~ 11 to 12 vdc with power on and without the bike running.
None will light a test light (to ground) with the power off.

 

Yeah? I'm checking the 3 wires going into the tail light/brake light bulb connector plastic PLUG. I'm assuming when you said SWITCH we're talking about the same thing.

With the key turned OFF, all 3 light the test light. Hmmm.....

 

Duh. Figured it out. I had the test light hooked up to the POS battery terminal instead of the negative. Rookie mistake. I found the right wire. Carry on...

 

Glad you found the right wire! Sometimes test lights are confusing. That's why i usually use a meter.
(And sorry for writing switch when I meant plug. LOL on that. I should read what i write before i hit "post".)

 

Why is this an issue? Is this different than if you had the cord in the car, plugged in, and no GPS connected? It isn't going to hurt anything to have power applied with no draw connected.