Can't find contact points for horn: 1971 R60/5

Discussion in 'Airheads' started by ozujiro, Jul 16, 2012.

  1. ozujiro

    ozujiro n00b

    Joined:
    Jun 1, 2012
    Oddometer:
    6
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    New York City
    Hi All,

    I am new to airheads and to this community. Excited to be riding a 71' R60/5. The bike I have is in great condition, but it did not come with a horn installed. I did buy a horn from Max BMW, and tried looking for the wires (2 green and 1 black) under the tank but did not see any. I am working off of the electrical diagram from the workshop manual, but am not having any luck finding the wires.

    Is there anyone out there that has a photo of the wiring to the horn or any advise that can help?

    Thanks.
    #1
  2. disston

    disston ShadeTreeExpert

    Joined:
    Mar 22, 2011
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    11,987
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    If you have the wiring diagram you should be able to say where the wires come from or identify some intermediate point. Find this. They start at the left hand handlebar control. Start there.

    Horn wiring has often been changed to add a relay. A good modification because a relay handles power better than running it all through the handlebar switch. See if the wires that should go to the horn are actually going to a relay.
    #2
  3. ozujiro

    ozujiro n00b

    Joined:
    Jun 1, 2012
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    6
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    Thanks Disston.

    I think I found the wires but when checking with the digital amp meter, only about .04 volts go through when the button is pressed. The old wires seem freyed, which I will try to replce.

    While I had the battery on (engine not running), I noticed the coils were really hot. Do you know if this is normal?
    #3
  4. disston

    disston ShadeTreeExpert

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    I have less of a problem working on my /6. It has a kill switch that I can use to stop elec going to the ignition. You don't have a kill switch and if you turn on the ignition to work on something the elec would flow thru the points and the coils if the points are closed. You could pull one of the wires to the coil or a lead going to the condenser if the cover is off. It is probably not a good idea to drain the battery or heat the coils up too much. I have heard that this can burn up ignition points.

    BTW, it is the completed circuit that flows elec. So any wire discoed stops the flow.
    #4
  5. ontic

    ontic

    Joined:
    Jul 14, 2008
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    Location:
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    also, the completed circuit earths through the horn button into the handlebars (via one of those tiny slotted flat head screws in the button housing).
    I had one of those screws out one day when doing some work and decided to test the horn- not working... that one took a while to figure out:lol3
    #5
  6. ozujiro

    ozujiro n00b

    Joined:
    Jun 1, 2012
    Oddometer:
    6
    Location:
    New York City
    Thanks Ontic and Disston for your tips.

    The horn is installed and works perfectly!

    Taking the bike to get the inspection tomorrow, which will make it completely legit in NYC. Excited.

    :D
    #6