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At What Point is an Accessory Relay Box Recommended?

fleetingyouth

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Over the years I've always intended to wire up some electronics and accessories on the bike but it always got put off and guess I never really needed them enough to get the job done.
I have acquired a variety of parts to install at this point and think it's time to install them.
A while ago I picked up the Honda harness and relay. I have a USB port and voltmeter display. I also have a leed to my battery jumper so I don't have to use cable clamps.

Ultimately I don't have a lot of need for accessories I have been looking at heated gear like a jacket or maybe gloves but I don't know if I'll ever pull the trigger.

I enjoy modding my bike and making it my own like a lot of you and If it makes sense to wire in a relay box I'd rather do it right the first time rather than redo it later if I need to. However, I also realize I don't have a lot of things that need power and I've had the bike for about 8 years with no issues so maybe my interest in mods out ways my actual needs haha

Also Second question the connectors on the accessory sub-harness are they standard? Or do most people just cut them off and wire directly into it?

Thanks all
 
I have the Honda sub harness installed and have my GPS hooked up to it. I got some of the factory connectors and attached them to the gps wiring harness. I had the factory heated grips which were also plugged into the harness. I like using the oem connectors as it makes for a really clean install. I still have unused connectors for auxiliary lights. Don't see the need for a relay box. I have a heated gear harness wired direct to the battery since that doesn't need to be switched power. I also installed my own heavy duty 12v socket in the frunk on a 15 amp circuit direct to the battery since I use it for the compressor in my flat tire kit.
 
I went to an Eastern Beaver accessory box immediately and never bothered with the expensive Honda accessory harnesses. It has three outlets and all three only work with key ON and have individual fuses. They easily power my GPS, voltmeter, elec jacket, and power outlet for phone charging without any problems. :)

 
When you can’t get enought power from the Honda harness, or you have too many ring lugs stacked on the battery post, you need a power distribution device. My preference was the Fuzeblocks. It has six 12-volt outputs. You can easily select whether each output is constant on or on only with the key switch. Even after it’s wired up, you could decide later whether to have an output switched or unswitched and easily make the change

 
I agree about the folly of having too many ringed lugs on the battery posts!

Those lugs are typically made of relatively soft metal and after a short time, they distort and you end up with a loose connection at the battery that can also affect starting and running, not to mention draining the battery if you forget to turn OFF the accessory. I limit the accessory pickups at the battery to no more than two, ideally one. :)
 
it was the damned battery posts that did it for me. I had a 12v outlet, my GPS, SAE pigtail for multiple uses, and heated grips. I wanted to add some aux lights. I had too many lugs on the battery and it was a huge PITA, and in addition everything kicked on at once and I was worried about overloading the battery or system.

So I installed a Innov PowerHub ... easy peasy. Connect it to the battery, and one line to an ignition trigger (I used the turn signal wire under the left hand duct). Simple posi-taps to connect everything, and everything is on a common ground. A few seconds' delay in turning things on to buffer the system. Easy. Love it. Very easy to add or subtract items.
 
Also Second question the connectors on the accessory sub-harness are they standard? Or do most people just cut them off and wire directly into it?
Those 6 pin accessory connectors are just another way for Honda to push their own accessories, which of course have the matching connectors.
You can cut them off, or better yet, don't bother with buying Honda's accessory harness kit (relay and fuse), and just go directly to the aftermarket fuse block of your choice as others have suggested.
 
In defense of the Honda accessory harness, early versions of the harness included a high beam signal that made it very convenient for wiring in a multi brightness level Skene controller for auxiliary lights. I have my aux lights and heated grips wired through the Honda harness, which is utilizing the accessory relay as well. I also use one of the harness outputs to trigger the switched input on the Fuzeblock accessory block for additional electricals. In this manner there was no need for me to tap or splice into any wires in the motorcycle’s wiring harnesses.

I purchased matching connectors for a neat installation. There was once a thread that gave a source for the matching connectors, but with the forum software change, that thread is apparently gone.
 
There was once a thread that gave a source for the matching connectors, but with the forum software change, that thread is apparently gone.
If these guys don't have the connectors needed, no one will:


Also Corsa-Technic and Eastern Beaver,
 
This question has been asked and answered a number of times but the "goods" may require a lot of digging. So here's an answer I gave earlier:

"Trying to stack too many connectors directly to your battery terminals is a recipe for problems in the future as its very difficult then to keep the connections tight enough that they won't vibrate loose. Way better to use some form of power distribution such as an Eastern Beaver block and/or the OEM Honda accessory subharness.

While there are some Honda accessories that connect directly to the accessory subharness, matching wiring terminals for your own accessories are readily available on the internet.

There are 3 connectors to play with once the subharness is installed – 2 of them have 2 wires (brown and green) and one of them has 3 wires (brown, green, and blue). In all cases the green wires are ground and the brown wires are switched 12V+ from the accessory relay and fuse. For 2016 and earlier model years, the blue wire seems to be +12V on high beam (per wiring diagrams I've seen). For 2017+ model years, the blue wire is the 5V+ Lo Beam signal. Matching companion connectors are readily available at cycleterminal.com (an SC110-3 connector will plug into a 2-wire connector and an SC110-4 mates with the 3 wire connector). I used the 3-wire connector for the aux lighting; the two 2-wire connectors can be used to supply power for any other purpose, like running a GPS or charging a phone or whatever as long as the total load (including OEM heated grips, if installed) thru the fuse is around 7 amps or less." (emphasis added)

For that matter, 'tho I haven't looked I suspect that the accessory harness plug that comes on the NC7XX probably also has a matching stock connector that's available at cycleterminal.com. In that case, it'd be super easy to just roll your own accessory harness that connects to the bike's plug. My reading thru this and similar threads leads me to believe the Eastern Beaver setup uses such a connector (can anybody verify?)

Using the on-bike plug for aux power, with or without Honda's OEM accessory harness, has a number of benefits. First, it allows accessorization without having to tap into or splice into the wiring harness - it's "cleaner", easier, and much less likely to fail over time. Plus it's easier to troubleshoot. Second, there's already a location provided in the fuse panel for a switched relay and (7.5 amp!?!) fuse - again leading to a cleaner and more reliable install. Third, there's separate line in the on-bike plug with a hi/low beam signal (if you've got a 2018+ model, using this signal may require a bit of finagling with a relay to convert the 5V-on-low to a 12V-on-hi beam - it's no too hard).

The main downside to this install is the limited amp capacity of the fuse - but I'm able power OEM heated grips, aux riding lights, a sealed 5V power supply for cell phone/GPS power, and a garage door opener - and that this power is switched is a benefit 'cause I don't want any of these drawing power when the bikes not running. Separate fused wiring direct to the battery provides a high amp connection for a tire pump and heated jacket.

If you need separately fused connections or require more than 7.5 amps, an external fuse block is clearly the way to go.
 
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For that matter, 'tho I haven't looked I suspect that the accessory harness plug that comes on the NC7XX probably also has a matching stock connector that's available at cycleterminal.com. In that case, it'd be super easy to just roll your own accessory harness that connects to the bike's plug. My reading thru this and similar threads leads me to believe the Eastern Beaver setup uses such a connector (can anybody verify?)
Eastern Beaver sells a lot of wiring solutions for the NC750, and yes several of them are specifically for the accessory harness.

Link:

 
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