Hi/Lo beam wiring

Discussion in 'The Garage' started by kellymac530, Jun 27, 2013.

  1. kellymac530

    kellymac530 motorcycle addict

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    On my R1100RT the bike had a single bulb headlight with a low and high beam switch that went from low only to high only.

    I am now running a Ninja 650 headlight set up and it has 2 separate bulbs, one for high, and one for low. I asked the other day and the left bulb is low and the right bulb is high.

    I am thinking of wiring so that both will be on when it is on high beam.
    Is there any issue with doing that as long as my wiring is set up correctly? Can the housing handle the extra heat?

    I am going to run the low beam power directly from the load relief relay unswitched after the key and then the high beam just wired on an on/off switch by using 2 of the terminals on the hi/lo switch on my dual sport control....any issues with this set up?
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  2. advNZer?

    advNZer? Long timer

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    i would run it through a relay if it doesnt already.Use the outputs from the headlight switch to trigger the relay(s)
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  3. kellymac530

    kellymac530 motorcycle addict

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    The low beam would be wired direct through factory relay. You are saying to run the high beam through a second relay after the hi-beam switch and use the switch just to activate that relay....that is a good idea, I will look at it. Thanks
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  4. bmwroadsterca

    bmwroadsterca RadioFlyer

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    I did this kinda thing many years ago on my Yamaha RD250. The headlight was pathetic. I wanted more light on high beam. I decided to try setting it up so both beams came on when the high beam was switched on. The following approach worked fine. The only caveat is that the wiring that supplies current for the high beam be capable of supplying enough current for both beams.

    A diode of sufficient current carrying capacity is placed between the high and low beam power leads. A diode will only conduct in one direction. You wire it in such that the high beam power will flow to the low beam. The low beam current is blocked from powering the high beam by the diode.

    mike
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  5. broncobowsher

    broncobowsher Long timer

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    The quick and wrong way to do this is the jump the power feed to the dimmer switch to the low beam. This makes the low beam always on as the switch cannot break the jump. This will not hurt the switch as you remove nearly all the current passing through it in low beam and in high beam it draws normal high beam current (low beam is powered by the jumper. Bad part is the feed wire is probably going to be overloaded now since it is now powering twin bulbs continuously.

    If the stock wiring is good (that model of bike isn't known for electrical issues with the headlights) I would jump the feed to the low beam. But use the high beam switch to trigger a relay. The relay draw is so minor it is irrelevant. While people tend to love relays to fix all kinds of problems (real and imaginary) I try to avoid using them needlessly. They are an electromechanical device that has both electrical things that can go wrong and mechanical things that can go wrong. I use them when needed, but avoid them when the gain can't be outweighed by the added complexity and additional failure points.
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  6. kellymac530

    kellymac530 motorcycle addict

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    On the BMW the Hi and Low beam have completely separate feed wires to the bulb. The switch just selects which wire gets the power. I just ran the low bulb direct to the bulb and then on/off switched the high beam.

    I also am not the worlds biggest fan of relays...seems like alot of stuff to just run low voltage wiring through. I usually runn good quality switches and fuse blocks with quality wiring and I have never had a problem. The Hi and Low still have the factory relay in place, I just routed the wires and switch differently.

    It seems to work great. So Far...:lol3
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  7. aardschok

    aardschok Fallout Rider

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    Volts don't matter much. Make sure your "quality" switch and wire is rated for the total Amps.
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  8. kellymac530

    kellymac530 motorcycle addict

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    It is all the OE BMW wiring. I am ok with what I have...seems great so far.
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  9. Motomedic

    Motomedic Over-caffienated Raconteur

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    I use relays, controlled by the OEM headlight wires from the switch for two reasons.

    One, so the headlight bulbs get as much voltage as possible, to maximize light output. A drop of 2 volts dims the light output by a noticeable amount. I forget the exact specs, but Google can help you with that if you're really interested in max output. Pre-relay voltage on my bike was around 11.5, post-relay shows battery voltage (or more accurately charging voltage) of 14.3 or so at the headlight connector. Much better.

    Two, as I use a high-power bulb (110/80 watts), the power draw doesn't go thru the switch. I can replace a relay in 5 minutes, and buy one at any auto parts place. My KTM switch would be way more of a PITA to replace, and no doubt made of gold for all the money KTM (Keeps Takin' Money :D) wants for its parts. By running relays, the switch only has to control a low-draw load, extending the life of the contacts.

    A two-relay system that would light both bulbs on high would be easy. Once again Google is your friend, but I'd start with a company called Eastern Beaver. :D
    #9