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Wiring LED Lights

brittrunyon

'92 R100GS
Being an amateur at motorcycle electrics,
& don't want to start a fire.......
I wondering if it's as simple as the schematic shows?
Any info would be appreciated.

<a href="http://www.flickr.com/photos/brittrunyon/10056072453/" title="Wiring Lights_62638 by No Rules Digital Imaging, on Flickr"><img src="http://farm8.staticflickr.com/7305/10056072453_03ceebc70f.jpg" width="496" height="500" alt="Wiring Lights_62638"></a>rl]

The bike is a '92 GS
The lights are AdvMonster 30 LED off road spot
1500 lumen
.85 amps @ 12v
http://stores.advmonster.com/-strse-8/Model-30-LED-off/Detail.bok
 
My only recommendation is to drop the fuse size. With the LEDs pulling about .85 amps each, a 15 to 20 amp fuse is too large. The fuse is there to protect the wiring in case there is a short. Unless you use large gauge wire (12 or 14 gauge), the wires could melt before the fuse blows. I would use a 5 or 7.5 amp fuse.

Wayne
 
With less than 2 amps of load, there are many switches that can handle it directly without the relay - simplifying the simple even further.
 
It would work as it is shows.

The only decision you would need to make is the power source for prior to the switch. It suggests "Low beam," High beam," or battery. You need to decide when you want the lights on. ONLY when the low beam is on? Only when the high beam is on? Or anytime (battery). Keep in mind also that you still may want to run the whole thing through the main ignition switch so that the only time these lights can be on is when the ignition switch is on. Use a power source from the main ignition switch that is only hot when the ignition switch is turned on.
 
Use a power source from the main ignition switch that is only hot when the ignition switch is turned on.

Turned on or engine started? Seems like you would want to have the ability to switch it on only after the engine is started so as to not put extra load on the battery when starting. Aren't all circuits energized when the ignition switch is on? I realize the later bikes have the extra circuit to switch off the headlight during starting...especially those that don't have a separate headlight on/off switch.
 
Turned on or engine started? Seems like you would want to have the ability to switch it on only after the engine is started so as to not put extra load on the battery when starting. Aren't all circuits energized when the ignition switch is on? I realize the later bikes have the extra circuit to switch off the headlight during starting...especially those that don't have a separate headlight on/off switch.

I had thought of that, but this diagram shows an individual switch for these lights so I assumed that the owner would switch them on/off when he wanted and would know to turn them off when parked or garaged.
 
if you pick up the switch power at the headlight they will only run when the headlight is on

And if you want to get tricky and have them rum with either high and low beam but still shut off with the headlight take the #85 that goes to ground, and put it on the low beam wire and the power to the switch on the high beam wire. The "ground will be supplied through the unlit filiment, but the amps are so low, it will not illuminate it.
 
I have a "unused" switched (powered when ignition is on) wire in the main harness under the tank that I plan to use as power to the switch.
Not sure why it's there but I think I'll use it.
That way power to the switch will be off when the ignition is off.
I don't want to have to remember to turn the LED lights off each time I get off the bike.

I'm using the OEM Hazard Warning Switch #1 which has very small wires, not sure of their size.
<a href="http://www.flickr.com/photos/brittrunyon/10067333716/" title="B0001942 by No Rules Digital Imaging, on Flickr"><img src="http://farm8.staticflickr.com/7386/10067333716_ff753fc658.jpg" width="500" height="353" alt="B0001942"></a>

Yes a smaller fuse would be more appropriate.
What gauge wire can/should be used for this installation?
Since the LED lights draw so few amps,would it really be a problem if starting the bike with them on?
Could I actually not use the relay?

Thanks Folks
 
Go here to look at a chart of amps vs gauge. http://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html I would use 16 gauge, 18 would work too since the wire will be so short and less than 2 amps. Too small a wire and it is more easily damaged. I doubt you will notice any changes in the way the bike starts if you have the LEDs on, you are pulling so little current. As an example, I recently tested the starter and battery on my 12 horse riding lawn mower (U1 battery). It amazed me to see it pull over 100 amps at initial start, dropping off to about 50 amps as the starter spun up to speed. I think an airhead would be about the same.

Wayne
 
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