Where to add in power outlet??

[cegan09]

I want to add a 12v power outlet to the bike so i can use a GPS for long trips. (my battery is abysmal.) Where is the best place typically to add it to the harness? What protections need to be taken? I'm not electrical genius, but i can work my way around a system. Ideally i'd like the outlet to be switched with the ignition so that i can't drain the battery when the bike is off. Any help is appreciated.

[bznchris]

can't speak for the 500, but the xs400's charging system is barely adequate to keep the batt charged. I wouldn't think a gps would draw enough power to upset the balance, but I don't know. I'd test it out as best I could before a road trip. having your battery die 30 minutes from home is a big enough pain. trust me.

can you find out how much power it draws? you ought to be able to connect it to the ignition switch circuit, after the switch. going straight to the battery would be easier though. you just have to remember to turn it off! I'm sure somebody who's put one in will weigh in soon.

[HoughMade]

A map and a sense of direction draw 0 watts.

[cegan09]

A map and a sense of direction draw 0 watts.

Yea yea yea. But sometimes a GPS is just convenient. I'd love it for long all day rides to places i've never been. I bought the charging system gauge off MikesXS that i plan on wiring in somewhere, so i could make sure the battery was seeing enough power. I can't imagine the GPS draws much power at all.

[Gas up - Let's Go!]

can't speak for the 500, but the xs400's charging system is barely adequate to keep the batt charged.

I've no idea if this is the case or not, however, there are some things you can do to recoup a little power.

By replacing as many bulbs as possible with LEDs you will regain a few Amps, it really depends on your GPS but generally they take very little power. A typical bulb will take around 10w, sometimes 5w so the gains are very slight but may just tip the balance between charging and draining a battery.

To run a circuit you could just take a power feed off the battery, but you should install an auxiluary circuit (a relay that provides power when the bike is running).

First you need to find out the power output of the stator, and the draw of the bike - I can't help you there, but a workshop manual would be a good start.

[ebike_tool]

I don't know if this helps but the turn signal relay has a line that is switched from the ignition key (on xs400). It may prove to be the easiest place to splice into. always make sure to fuse any connection you make! use as low a rating as possible (ie. if the gps requires 1.6 amps then 2.5 amp fuse would be more than enough)

[cegan09]

Cool, thanks guys. First i'm going to give my charging system a nice once over to make sure it's ok, probably replace a lot of it just for piece of mind, then address blinkers. I've been meaning to put different blinkers on for a while, and if i can go LED I'd love to. I'm also going to make a custom wiring harness at some point. Not much changing, just want to move the ignition switch, be able to hide things better, and have a harness that isn't using 30 year old wire.

I believe the power chord for the GPS has a 3amp fuse in it, so i'll match that for the fuse i wire into the socket line.

[Speedshop]

Sat navs are fairly power hungry, there's a receiver and processor running all the time.

If it were my bike I'd feed a relay directly off the battery, via a fuse (this will protect the circuit). The output of the relay I'd supply my accessory socket from.

On most Yamahas the brown wire in the loom (do not confuse with the brown on the left indicators) is live only when the ignition is on. I would use this to control the relay IE Ignition on = socket on. Ignition off socket dead.

Feeding directly off the battery puts no extra load on the wires in the loom plus you avoid loading the contacts in the ignition switch. But thats just the way I do it if you bought your bike to my workshop.

If you want a simple lash up connect the socket direct to the brown feed. You will be running the brown wire very close to its maximum rating, plus feeding through the contacts in the ignition switch. You'll get higher losses this way, but it will work.

Switching to LEDs is a good idea.

[Gas up - Let's Go!]

I believe the power chord for the GPS has a 3amp fuse in it, so i'll match that for the fuse i wire into the socket line.

So your GPS is using less than 36watts, bugger all in power terms (compared to 10 watts from a tail light) but you're going to struggle to recover this power by using LEDs. Indicator, sorry blinkers will either need a replacement flasher unit or in-line resistors to work correctly. The net result is you won't realy save any power (but they are much brighter), the only savings are going to come from the stop/tail light or headlight unit.

There are LED headlight units you can buy, but the light these put down on the road isn't great - depends where you ride? Great for city or illuminated areas (from streetlamps) but crap on country roads, but it's an option open to you.

One rule you could use to allow you the power is to only use the GPS when you don't use your headlight ? at least then you know you are safe (assuming the bike has the power to run all it's OE electrical items....)

[Speedshop]

Lets think about this........

36 watts at 13.8 volts = 2.6 amps.

55 watts at 13.8 volts = 3.9 amps.

So your sat nav IS NOT 'bugger all' power in terms of the system's capibility, its in fact drawing more then half what the head lamp does. If it's internal battery is flat I'd bet it draws a damn site more, I wouldn'be surprised if it took 2 amps to charge its battery - so it would be like adding a bigger second headlamp!

Most of the wiring on the bike is 1mm squared area with a 11 amp rating. Lets think about that, headlamp 4 amps, instrument lights, pilot light and rear lights lets say a total of 25 watts, so 1.8 amps. So your lighting alone is drawing nearly 8 amps. Admittedly this won't all be felt on one single 1mm squared wire.

Your ignition draws 2 amps and you have to consider battery charging which varies, but could be as high as 4 amps (normally less then .5 amp)

So engine running lights on theres 8 amps, 2.6 amps is approx a 33% increase in load.

If you replaced the tail lamp, pilot light and instrument lights with LEDs you'd free up something like 1.25 amps, so it is worth doing. If you have a twin bulb tail light, LEDs are bright enought to just use one, freeing up more power

(the XS650's charging system is even more marginal then the XS400. I have fitted LEDs in all lamps bar the headlamp and now there is never an issue with battery charging or bulbs blowing)

[Gas up - Let's Go!]

So your GPS is using less than 36watts, bugger all in power terms (compared to 10 watts from a tail light)

So your sat nav IS NOT 'bugger all' power in terms of the system's capibility,

If you are going to SHOUT about it, perhaps you might want to get your ducks in order first ?

Fuses are over-rated meaning that the suggestion of 36 watts is a maximum (based on the current fuse), and in all probablity the GPS is using something like 10 watts (A Garmin Zumo only draws 15 watts with bluetooth in opperation). As I have suggested on other posts, a relay should be fitted (so the argument on the current draw through the current harness is of little use here) and it's a fine line in any case. I would never recommend running accesories or any kind through OE wiring, always fit a fully fused auxiluary circuit.

The argumnet is further flawed as there is an assumption that there is insufficient capacity to provide extra power, when this hasn't yet been properly established. Without the data on power consumption of the <electrical> components of the bike and the output of the stator then a power budget cannot be established.

-----

Another option is to look at getting the stator rewound, you can gain some extra watts here, so long as your rectifier/regulator assembly can take the load. If you are replacing the main loom then this is an opportunity to upgrade the whole system and give you what you want.

[Speedshop]

Hehehehe someone got out of bed the wrong side

Its well documented the XS 400 has marginal charging. I've not had good results rewinding these generators to give more power - they have an odd fixed field winding which limits their potential . Expensive too.

[cegan09]

Again thank you for the wealth of information. I'm a mechanical guy, so help with electrical is always appreciated. I think the plan moving forward will be to address the charging system, make sure everything is working properly, replace anything that needs it. following that replace things like tail lights and indicators with LED, replacing the relay if possible so as to actually gain a savings from LED. Then finally make the new harness so that i have new wiring in the bike. when i make the new harness i'll add in another auxiliary switched circuit.

[HoughMade]

Some time in my bike's past, someone installed a cutoff switch for thr headlight. As designed, my headlight would be on whenever the engine is running. I think in the U.S. we are not required to keep the light on all the time, so during the day, there's an easy and cheap way to create some extra capacity. I don't know if your bike has the constant on headlight, and I know at some point before '79 (my bike's year) they had a headlight switch. If yours has the cutoff switch or it does not, but you add one- daytime running with the GPS should be no problem withe headlight off. Think about it. If the bike runs reliably with the headlight on, cutting it off will free up 30-60 watts (depending on the headlight).

[cegan09]

My headlight doesn't run constantly. I have a switch on the right hand controls that turns it on and off. From the looks of it the switch was stock.

[HoughMade]

There you go- during daylight hours, there should be no problem whatsoever.

[Cynic]

There you go- during daylight hours, there should be no problem whatsoever.

Not always, sometimes the lighting circuit charges the battery when its off.

I'm with GAS on this though, 3A fuse is a safe short circuit current so you are looking at a real world max of 1A continuous and that will include stuff like battery charging.

All you really need to do is make sure the battery is in good nick and be certain its fully charged before your epic . With the capasity of modern sat nav batteries you may do most of your ride before the sat nav is even drawing any real power.

My sat nav will happily run from the PC USB plug used to download new maps, that is not going to stress any motorcycle electrics no mater how marginal.