Relay install for heated grips

Run 30 to battery plus (via a fuse);
85 & Return from grips to battery -ve
87 is output to Power for Grips
86 is from switch for grips; input for switch from any source that is on with ignition.

You can select any convenient line that is only powered when ignition is on - the power through the switch is minimal as it only powers the relay - so you can use virtually any source without compromising anything. The main power for the grips will come directly from the battery.
Just pick a wire that is convenient to your switch.
If your switch is on the left handlebar, then you can tap into the blue wire in the harness that runs up to the left bar switch (main/low; turn; horn etc) (or pick it off near the connector plug off that same harness)

Ideally you want the switch on the coil side rather than sending the heater current through it. That would mean running the wire all the way up & back from switch to the battery end and all the way back up again for the power.
But if switch is designed to take that current, have at it I guess.
My preference would be as shown. Convention is to switch the relay coil, not the load line.

Sure, as above, any source for the relay power is fine.
Green wire on either the fall detect switch or the ignition relay is good.

Marks Daytona said:

... I was wondering if the numbering differs for different relays ...

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They are always the same - the other terminal that could be present is 87a - that is the Normally Closed contact
N/C is exactly that - 30 is connected through to 87a and when the relay is energized opens 87a and switches 30 to 87 instead.

You can buy relays that have built-in fuse holder for the 30 input and/or with the diode already installed.
Those are added features that make installation simpler - one stop shop so to speak.

Spot on!

DEcosse said:

But if switch is designed to take that current, have at it I guess.


You can buy relays that have built-in fuse holder for the 30 input and/or with the diode already installed.

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My friend, you are on the ball! Yes, I bought the relay with integrated 15a auto fuse. As you say, I can clean up the wiring and take out the in-line fuse. I guess I should change the 15 a fuse for a 3amp now that I think about it....

Also, I totally agree with the preferred wiring set up and I now understand why you thought the relay would be up front, but the switch seems to be built for the current so I will take full advantage of that . I have scanned the wiring diagram they supplied to show you. Thanks again, you are clearly a wealth of knowledge.

It will be good Mark - they weren't even using a relay at all. 3A is not huge current (but as you rightly recognize would certainly kill your battery in short order!)
As you say, eliminate the in-line fuse and use the built-in realy slot, but swapped out for a 3A.

M/W said:

.... He told me that if I hooked into any wire the computer would shut the whole system down because it detects any voltage draw change. Does he know what he's talking about?

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:BS Flag