I have 1 terminal, but I need 3 cables attached.

Discussion in 'Old's Cool' started by LasseNC, Mar 25, 2012.

  1. LasseNC

    LasseNC XSessive!

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    Hello!

    I am making the wiring harness on my GT380 caferacer. The headlight I have is a british styled unit, with a "british style" contact.

    It has three positions, OFF, LOW, HIGH.

    When I switch to LOW, I want the Horn, Low Beam, Rearlight and Ignition to be on.

    Problem is, there is only one terminal.

    So my question is, how do I avoid piggybacking it all?
    #1
  2. England-Kev

    England-Kev Long timer

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    you really should fit an ignition switch before that off/low/high light switch. it would make it all so much easier...

    [​IMG]
    #2
  3. usgser

    usgser Long timer

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    If you're using a Brit (Lucas) 3 position light switch. It's OFF/DIM/FLICKER.
    Sorry couldn't help myself.
    #3
  4. LasseNC

    LasseNC XSessive!

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    Easier than finding a suitable way to get three spades on one terminal? I doubt it Kevin.

    It would been that I'd have to source an ignitionswitch and use alot more wires, plus where would I put it? :) I'm going keyless minimalistic.
    #4
  5. trumpet

    trumpet Group W Bench

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    [​IMG]

    A terminal strip, like this. Mounted out of the way, can provide a solid way to build branch circuits.
    #5
  6. LasseNC

    LasseNC XSessive!

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    Was thinking about something like that, but can't find these around here.
    #6
  7. Zoef zoef

    Zoef zoef Been here awhile

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  8. mike in idaho

    mike in idaho Been here awhile

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    Use a six pole, double throw switch. Run power to both center terminals, high and low beam to the end terminals on one side and your horn/ignition/brake light to both terminals on the opposite side. Bring the horn/ignition/brake wire out of the headlight shell back to a small 4 fuse box under the seat, you can run wires to everything from there. Not truly minimalist, it substitutes a fusebox for a multiple splice.
    #8
  9. LasseNC

    LasseNC XSessive!

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    Hi Mike

    Do you have a picture of one of those? I am not sure I understand.

    Here is what I did as a temp. way, I know it is bound to fail.

    [​IMG]
    #9
  10. lrutt

    lrutt SILENCE.....i kill you

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    so what do you want when it's on high beam? same thing? if so, unless you use diodes or something, you'll get feedback through and not get what you think you'll get.
    #10
  11. LasseNC

    LasseNC XSessive!

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    How so? That doesn't make sense to me.

    High beam is located in the switch itself, and not in the bridge, but when High is on, both High and Low will be on.
    #11
  12. Nessman

    Nessman Evangelical Atheist

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    I don't like to run that many functions through one switch. How about the LOW position tripping a relay for all functions (or most of them). The switch is designed for a headlight only, adding more current will make it fail prematurely.
    #12
  13. LasseNC

    LasseNC XSessive!

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    Do you know what such a relay is called? Sounds like a good idea.
    #13
  14. caponerd

    caponerd Kickstart Enthusiast

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    The airhead BMW's use such a relay for the headlamp and horn.

    I can't think of the part number offhand, but it's a very generic item that you can get at any auto parts supplier for $5-$6 (or euro equiv.), or from any BMW motorcycle dealer for $60. :rofl(yeh, I know, there's a diode in those, which wouldn't be needed in this application)

    Someone in the airhead section of this forum can fill in the blanks.

    <edit>
    of course, if you're really looking for minimal, why not wire the ignition direct to the voltage regulator and use a battery eliminator (really big capacitor)? Then all you have to connect to the switch are your lights and horn.

    Depending on how your electrical system works, you might be able to get away without adding a battery eliminator. I run my BSA 441 with no battery. I have to switch off the lights before I try to start the motor, but once it's running, the alternator (Lucas!) can handle the motor and the lights just fine.
    </edit>
    #14
  15. Nessman

    Nessman Evangelical Atheist

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    Apologies Lasse, I didn't have time to detail my relay idea, I'll try tomorrow.

    You want to use the light switch as an ignition switch right?

    How many wires does your switch have? I'm assuming three, power in, low out and high out.

    Do you not intend to use the high beam wire? If all the functions you mentioned need to work on both high and low settings it's a bit more difficult.

    Handlebar kill switch? Dash (instrument) lights? They both get involved in the wiring if you have them.
    #15
  16. LasseNC

    LasseNC XSessive!

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    I'd like to ditch the battery, but I need it for inspection, as I need to have a light on the bike, with the engine turned off. Can be made after inspection though.

    I have 5 poles on the switch in total, but when I turn to use the functions some of the poles goes "off" and are therefore not usable.

    Kill switch? Not needed, I can just turn the mainswitch. No instruments.

    I want, horn, rearlight, front light and ignition on, both on High and Low beam of course.

    A simple brit style switch with horn and High/Low might be needed, although I dread it.
    #16
  17. anonny

    anonny What could go wrong?

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    Why not 1 wire out to with a female round connector that plugs on to a male with 3 out with females? Your basic 3 into 1 called pigtailing in the electrical trade.... I know Kawasaki did it in the 70's in the headlight bucket.
    #17
  18. Nessman

    Nessman Evangelical Atheist

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    [​IMG]


    Here's my idea, both the high and low positions trip the relay (#86 on the relay) sending power to the horn, coils and tail light.

    The only thing the switch is powering is the headlight (and a tiny amount of power to the relay), the wire to the #86 post can be very small because it carries almost no current. The wire to the #30 post should be 16ga (bigger if you want but 16ga should work fine).

    You need a battery (or big-ass capacitor) on the bike, the electrical system needs something to smooth the chaotic spikes and valleys in the incoming power. It was mentioned in another thread that your bikes electrical system is powered by the 12V battery, the 12V battery is charged by the bike.
    #18
  19. LasseNC

    LasseNC XSessive!

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    This seems doable, I will see if I can find such a relay!
    #19
  20. Nessman

    Nessman Evangelical Atheist

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    #20