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Setting up a relay

I have some accessories I want to add to my bike that I don't want connected directly to the battery so that it drains it when I forget to switch the accessories off.  So I have researched over the years and understand how the relay works, but I do not know where I can tie into a hot wire when the ignition is on.  So my question is that, where should I ( I really don't want to splice) splice into a hot wire to power my second relay which I intend to use to power an accessory block.  Any information is appreciated.  My bike is a vstar 1100.



OK Drew, here I go. there are 5 term on any Bosch relay. 85,86 ,2 / 87's, 30.
1: 85 should be Ground. I would ground to the battery grounding stud or the neg battery terminal.
2: 86 keyed 12 volt or switched from the fuse block. I think this is on the RH side of your bike.
Take a test light and find which fuse is keyed to the ignition switch. Install a ATO/ATC fuse tap on to the fuze. Use the output side of the fuse. The tap # is Standard ET 231 3/16 GM mini fuse tap. or ET 230 1/4 Gm fuse tap.These slid on to the blade then you can insert the fuse back into the fuse block..This eliminates the need to cut and solider wires.
3: 87's are NO or NC terminals. You will have to figure out how you would like to have that set. I use the NO term. When you have switched power it will switch to closed position. Thus power to your assy. You do not need any wire on the NC term.
4: 30 should be fused 12V from the battery. I have run a inline fuse 5-10 amp to 12volt positive from the battery. This line is hot all the time. It supplies the power rather than the on / off switch.
5: If in doubt there is a diagram on the side of all relays.
OK this is as easy as I can get if you need any more help just yell. IF anyone has any thing else to add
PLEASE do so. Some times I'm not the brightest bulb in the pack.
There you go Drew hope this helps a little.

Good job scruffy but where's the links for visual aids. Eww I like that fuse tap...awesome. Do you recommend any accessory block? I'm not sure I am calling it by the right name but you know. Wow great information, I just found most of the stuff I need at

depending what you are adding, i splice into my aux lights into my signal power wire and a chrome switch into the power for the headlight larger red.

they have improved splicers since the square red and blue ones.
i used these they also come in "T"s if you can find them
not a professional but it worked for me

Here take a look. I think this will give you a good idea on what is happening with a relay. Have fun Drew

eynstyn where do they sale those? Although the fuse tap is high on the want list. But I can see tapping into the ground wire( neg battery return) with the splicer.
Nevermind found them on ebay

Thanks again the information is very useful.

Someone correct me if I'm wrong but, doesn't your bike's fuse block have several reserved (unused) fuses?
The visual aid links (LOL) from one of my favorite sites. is from:
Please excuse my mild ocd. Just give me my blankie, some cookies and milk and tell me it's nap time. I'll go away and not bother you.

I'm checking. Great visuals Edwins.

87 vs 87a, if I understand correctly the difference is one energizes power loop when relay receives ignition power and the other cuts off the power loop. Is that correct?

OK got my schematic drawn out. Ignition has fuse in fuse tap to 86, and 85 to neg battery. Hot lead to relay from in coming soleniod hot nut to 30, then 87 to distribution block 30 Amp in line fuse. In line fuse from distribution block (fuse size varies to match device amp ratings) to device then to toggle switch, then to battery negative side distribution block, distribution block to negitive battery via quick splice or by plug and play ground....

Still checking on whether there is spare fuse line.

Where should I put the toggle switches. I am stuck.

Something like this.
mounted to something like this.
Just as a starter idea. Clamp it to the bars where you can reach it and it doesn't get in the way.

It's a start but I'd like em not obvious. Here my toggles. I am leaning to putting them underneath the side cover, which means I have to turn them on before riding or pulling over to turn them on. Where is Spad562 when you need him?

Or? Could use the idea for a self made one with a hinged chrome cover. There are some folks on here that could make one. and could be hidden

I just replaced the handle bar clamp with a tach...dough! Touch panel is interesting....but alas..."Sorry, this item is no longer available!"...Dough!

Windshield sounds good, maybe.

Still researching on spare fuse lines Edwins spoke about, but I think those are just holders for spare fuses. Not sure yet though.

Your right, they are spares. This just may be something you could use.

Yes that would eleminate the need to in-line fuses. Great idea. I am adding three accessories, heated seat, LED lighting, cigerette lighter/usb charger. I am going to make the charger direct to battery(always on). Any other accessories I should concider?

Heated grips to go with the heated seat. It does get cold in Cali. I'm going to be setting up a laser ground projection auxillary tail light. Ghost rider image,of course. The unit I bought is a bit flimsy so I'll have to built a better housing.
I'm going to install the fuse block for the laser, Johnnie's leds, and maybe a stereo in the sidecar. This is getting to be fun.

No doesn't get real cold here, but perhaps heated gloves. I really don't know what your talking about with pictures..hehe. Ya you sold me on the fuse box distribution. I am also going to get a ground distribution block...small one. I am sticking with the Ipod in the helmet with ear buds.

Look in Photos, I posted the pic. Gotta love pictures. lol Rode from Venice to Yucca Valley by way of Hemet and it freaking snowed???? Been to Big Bear. Yup. cold!

This place is full of helpful of guru's. And Scruffy!!!!!!!

Just a note. The Fuse Tap with a mini blade fuse is the one to get for Vstar 1100 for mine anyway 2008. Only complaint is the fuse lid on the fuse box will not close with the tap installed.

You can use 87 to power accessories and 87a to power an alarm system. Sweet now I have to figure out how to get a vibration detector.

You got it drew. This relay can be used for two different things this is why I use them. I have used the mini in line fuse holders. They are small and easy to hide plus there is a cover to keep the moisture out. Before you add too much stuff make sure your charging system will support the wattage or amperage draw. You don't want to be replacing the stator and regulator assy's.

That had crossed my mind. I got a cigarette lighter for the handle bars and was going to connect it straight to the battery, but I found a voltmeter that plugs into a cig lighter so I am putting it on the relay and use as a monitor to watch the voltage, and as an "ignition on charger."

Then under the side cover I am going to have an always hot cig/usb lighter for charging when ignition is off. This is where my relay is going since I removed the AIS pump and crap. It's going to sit on a piece of metal which will screw into old screw holes.

The heated seats comes with relay which I will power off the new accessory fuse box. I will hide the heated seat relay behind the steel plate I am hosting the 1st relay. Going to power charger with relay when ignition off...same with LED lights...can't get a ticket for parking lights and I'll have switches to make sure they aren't on unless thats what I want.

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