Both lights on high beam

Rcdan

New Member
I have been wondering about this for a couple of months. If you have ever held the passing light switch on when riding you know how much better it is than just the single high beam. I also noticed one of our vendors sells an LED upgrade and plug and play harness to have both lights on for high beam.
My thought is why not just solder a jumper wire from the power in to the switch to the wire out to the low beams. This would power up the low beams whenever the lights were on but also allow the high beam to be switched normally. I was looking at the wiring diagram and the power out to low and high beams is separate so it will not back feed or cause any other problems that I can see.
I plan on doing this soon and will post picks and let everyone know how it turns out. Seems simple enough though.
 

ToraTora

Member
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The system really isn't designed to carry that much load. They can do it with the LEDs because they don't require as much power.
 

Rcdan

New Member
Why do you say that? Not saying there may not be an issue but what specifically are your concerns. The euro verson runs both lights on high. Maybe they us thicker gauge wire or beefier relays but I doubt it. What part of the system would be the weak link in your opinion?
 

psych0hans

Member
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The system really isn't designed to carry that much load. They can do it with the LEDs because they don't require as much power.
Not true, as the Indian spec 390s have this as a standard feature. Our high beam has both headlights on from factory.
 

Rcdan

New Member
Just wanted to update. I soldered the connection right at the switch itself. Works perfectly and took maybe 45 minutes start to finish. Will post pics later. Awesome project and pretty easy if you can use a soldering iron
 

Rcdan

New Member
ok so here are the pics.View attachment 3326 this is what the switch looks like. It comes out of the housing very easily after you remove the passing light switch. each one is held in with one screw. the yellow wire is power in and the red that is partially hidden is low beam. you can verify with a volt meter. just solder your jumper from the power in to the low beam
IMG_1353.jpg here it is soldered in. now just tuck everything neatly back together and this is the result. IMG_1354.jpg
 
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ToraTora

Member
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Why do you say that? Not saying there may not be an issue but what specifically are your concerns. The euro verson runs both lights on high. Maybe they us thicker gauge wire or beefier relays but I doubt it. What part of the system would be the weak link in your opinion?

Look up the power rating of the stator. Look up (or read) the power requirements of the bulbs. If the power of the two bulbs exceed the rating of the stator then you'll know that you are exceeding the design of the system.

Much in the same way that going to LEDs would lower the power needs it is possible to use bulbs that use a lower wattage as well. This would be another way to stay safely within the limits of the system.

And do note that even if the two bulbs come in at slightly below the rating of the stator you still have to run all of the other electronics on the bike, and have some left over to charge the battery.

Here's the formulas for conversions. The bulbs will likely be in watts, and the stator in amps (which you can roughly calculate at 12 volts).

watt = amp × volt
amp = watt / volt
volt= watt / amp

Here you go. This has already been discussed on this very foro. Search is your friend. ;)

The running two headlights was discussed in a thread awhile back. I will try and search it out, but
FWIW, the alternator is rated at 296 watts and our North American spec bikes run 55 watt bulbs both high / low, no LED turn signals. The high beam is already controlled by a relay and there is a 'LCU' Lighting Control Unit, that ties into the ECU and is described as controlling low beam current when engine is at low RPM's. What I have noticed that has steered me away from doing any mods is that when I am sitting at a stop, no turn signals, cooling fan on and I pull the switch that flashes the high beam thus running both lights there is a noticeable change in the cooling fan speed. That indicates to me that there is not a lot of extra capacity in the alternator / battery for the additional 55 watts.
 

ToraTora

Member
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Not true, as the Indian spec 390s have this as a standard feature. Our high beam has both headlights on from factory.

And what are the ratings of the stock bulbs, and the stator (alternator)? The bikes marketed in India could easily have different specs than the bikes marketed else where. If indeed the bikes sold in India would have both bulbs light up supports my assertion. :D
 

Rcdan

New Member
Tora I have researched the wiring using the repair manual. The only unknown on my part is the capacity of the feed to the switch. As for the fan speed changing at idle I am not surprised as the alternator is way below it's max output at that RPM and the fan is a huge draw. The voltage reading at the battery does not change when at idle with both lights on. I guess I would say do it or not, that is up to you. But so far there is nothing to indicate an additional 65w is going to over load the charging system. Especially at normal operating RPM. I was a little concerned with load through the switch but as that is bypassed for the low beam that is not an issue. And by the way I operate power generators for a living, I am well aware of the formulas to figure load, but thanks for the info.
 

Splitfire

New Member
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Hi newbie here. I know this post is 5yrs ago. Hopefully someone will answer back. I have problem with my headlight high beam. Doesnt even show the blue high beam indicator on the instrument cluster. Low beam and daylight is working fine, both of my bulbs are fine. I checked the 4 pins connector on the side fairing. I suspect it's the headlight handle bar controll. I tried opening it. I removed 2 phillips. Pry it open and have no luck to fully remove it. Its like it's glued or something. Did I missed to remove some screws? . I really want to check my headlight controller
And I need to know the headlight relay controller if there is. I will check it too.
I have 2015 rc390 for reference.
 
ok so here are the pics.View attachment 3326 this is what the switch looks like. It comes out of the housing very easily after you remove the passing light switch. each one is held in with one screw. the yellow wire is power in and the red that is partially hidden is low beam. you can verify with a volt meter. just solder your jumper from the power in to the low beam
View attachment 3327 here it is soldered in. now just tuck everything neatly back together and this is the result. View attachment 3328

ok so here are the pics.View attachment 3326 this is what the switch looks like. It comes out of the housing very easily after you remove the passing light switch. each one is held in with one screw. the yellow wire is power in and the red that is partially hidden is low beam. you can verify with a volt meter. just solder your jumper from the power in to the low beam
View attachment 3327 here it is soldered in. now just tuck everything neatly back together and this is the result. View attachment 3328
Love the idea will maybe being doing myself. Appreciate the time to share lics and give brief explanation on what to solder together
 
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