Where are good grounding points?

Where are good grounding points on FJR? I've installed a 12v power strip to my bike for connecting auxiliary lights following the instructions posted by Warchild on FJRTech.com. It is suggested to connect terminal 85 of a relay to any good grounding points. Does anyone know where they are on FJR? I'm going to place the relay right behind the headlight housing area so it is near battery and side signal lights (to get switched power to relay).

2nd question: my aux lights have two wires. If one connects to the power strip, does the other have to connect to negative battery? If so, I'm curious multiple devices connecting to the strip would crowd the negative terminal of the battery. Is there alternative way?

Thank you so much.

Dai

The best grounding point would be a ground strip connected directly to the battery negative terminal. If you attach it to the outside of the battery box, all the wiring will be hidden under the upper right fairing panel.

Just install one as you did the power strip.

That negative post on the battery is the best.

+1 ^^^^^^^^^^^^^^^^^^^^

Go directly to the battery and put in a grounding strip and run all your add-ons through the power and ground strip. Minimizes the chances of ground loops which can drive your crazy later

Thanks Twigg and Ignacio! Why I didn't think about ground strip in the first place? Hihihi. That's how team work is better than one!

btw should I use 12 or 16 gauge wire for this ground strip?

Personally I would weld the ground side of the power strip to the frame with a heli-arc welder......just to be sure......you never know man, you never know.

fjrbird said:

btw should I use 12 or 16 gauge wire for this ground strip?

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No smaller diameter wire that what is feeding your power buss. Personally if you've not run the positive lead, I would use a 10 guage

Roy Epperson said:

<snip> Personally if you've not run the positive lead, I would use a 10 guage

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Yup ^^^^ I go with 10 ga for both positive and negative when supporting fuze blocks and/or grounding strips.

YMMV

--G

Great! In Warchild's post 12 gauge is used for power strip. So I think ground strip should be ok with 12.

fjrbird said:

Great! In Warchild's post 12 gauge is used for power strip. So I think ground strip should be ok with 12.

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Check the wiring capacity charts .... 12 gauge, at that short length is probably capable of handling the entire output of the alternator. If you have some spare 10 gauge you won't hurt anything by using it, but the thicker gauge wires get considerably harder to bend the way you might want them to.

I'm going to offer an alternate viewpoint.

For things like aux lights, heated gear, heated grips, etc. you can just use a good frame ground connection. These devices are not sensitive to electrical noise, and the battery negative terminal is tied to the chassis with a stout conductor that can handle any load you will add to it, so there is no huge advantage to running a large common wire all the way back to the battery. If you'll just be running the return from one device to a chassis ground there is no need to upsize that wire. Just use the same gauge as the power wire for that device, which is generally already on the power cord.

The only devices that need the ground wire run back to the battery are any audio sources or amplifiers (like intercoms, GPS, Radar Detector, etc.) since any ground noise can result in buzz or hum in the audio on those, and some of the more sensitive electronic devices like a Power Commander, which specifies in the installation instructions to run the black wire back to the negative battery terminal.

Sure, you can do the terminal strip thing if that works out to be more convenient for you, it just isn't absolutely necessary. For instance, I have two auxiliary power strips installed. One strip in the front that powers my Aux Lights and has an output to the strip under the drivers seat, which is used to power (his 'n hers) heated gear. For both of these strips I am just using frame grounds for the returns.

My electronics (GPS, RD, Starcom1, phone charger) are all powered out of my tank bag, which gets its power from a battery tender cable attached directly to the battery + and - terminals. That setup works fine.

YMMV

The main problem with "floating grounds" is that they introduce noise to audio systems and can cause issues with circuits. With the FJR there can be a different ground delta between the main chassis and a subframe.

Direct to battery ground, or to a strip connected directly to battery ground.

Fred W said:

I'm going to offer an alternate viewpoint.

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Doesn't the starter motor rely on the frame/engine case to conduct?

If that's not a strong enough endorsement, I don't know what is!

Frame, dude.........frame....and weld that mother to it......for all it's worth.

Yamaha thought that grounding to the frame was such a good idea that they introduced the "ground spider" to the Gen 2.

Unfortunately, they did it on the cheap and it needed others (then Yamaha) to fix what they broke. Nonetheless, grounding to the frame, even with a good solid weld is probably best avoided for most of us.

Modern vehicles have complex electronics, to which we add comms systems, radios and other assorted detritus. Avoiding ground loops is best done by having common grounds and keeping wire lengths (to and from an accessory) as close to the same length as possible. Shielding can help too as well as isolating adaptors.

Keep it simple, and let the frame hold the engine and wheels in the correct positions.

just my 2c

I see Odot has come out of hibernation and offering some very cerebral advice.

I have all my add-ons attached directly to the battery. Those are, Denali DM LED's (power drawl5watts), Garmin GPS, and battery tender pigtail. All three are in-line fused. Everything works fine. Are there any negative consequences to this method? Can't wait to see Odot's reply. By the way, I check'd the pumpk'n oil!!

Twigg said:

Yamaha thought that grounding to the frame was such a good idea that they introduced the "ground spider" to the Gen 2.
Unfortunately, they did it on the cheap and it needed others (then Yamaha) to fix what they broke. Nonetheless, grounding to the frame, even with a good solid weld

is probably best avoided for most of us.

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Actually, the ground spiders are exactly the opposite of running things to a common ground. Instead they join a bunch of device grounds together at a spider and then run them to ground together. That is the exact scenario that can result in ground loops, where you are sinking current from one device back through another one.

Twigg said:

Avoiding ground loops is best done by having common grounds

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This statement is correct, and the frame is about the most common of a ground plane as you can expect on a vehicle. It is attached to the battery and alternator return path via a relatively large, low resistance cable, through which the entire electrical system of the bike returns to the battery.

The subframe(s) of a bike may or may not be a good ground depending on how it is attached. In the case of the FJR the rear subframe has proven to be adequate.

YMMV