Harley Turn Signal Switch Conversion

Discussion in 'Road Warriors' started by foxtrapper, Feb 1, 2013.

  1. msells

    msells Been here awhile

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    I believe the Harley will be one inch (1") handle bars and that some new-ish big-ish metric cruisers also use the "fat" 1 inch bars instead of the usual Japanese 7/8". Do some reading and see if this is true for more than the one example I could quickly find ("Honda Shadow ACE" - http://www.hondashadow.net/forum/53-general-discussion/93762-handlebar-size-1998-shadow-ace.html seems to confirm this).

    I think newer Harleys may have more complex switch wiring that the pre-1990 stuff that I have played with. Notably, there maybe special things like turning on hazards (push both left & right at the same time?) that won't work with the new single switch setup and require some thinking.

    Good luck!
    #41
  2. Tripped1

    Tripped1 Likely Lost.

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    Like I said a switch is a switch, if there are enough poles it doesn't matter, its just how its wired up.

    .....of course Harley copyrights their manuals so I don't know off the top of my head, but assuming they are momentary action single pole single throw, you get a double throw/double pole and holding it down would be the turn signal activation.

    Most single switches are double pole double throw, two wires per side and the hold down grounds it. At worst you have to putz around with the relay. Right now my Speed Triple has a trailer turn signal relay because I'll be damned if I was going to pay Triumph $75 + shipping for a damn signal relay, I'll pay autozone $13 :lol3

    Anyone have a service manual and a know how to read a scat?
    #42
  3. stevie88

    stevie88 That's gotta hurt

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    Or you could just never use your turn signals.:deal
    #43
  4. msells

    msells Been here awhile

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    My initial point was that on the original "left on left bar, right on right bar" is that it's possible to engage BOTH switches at once. If you replace that with a "flip left or flip right" you can't flip it both ways to get your hazards on.

    Wiring is actually likely more complicated than that on newer (post 2000?) bikes ; the turn signals may be handled by the TSM / TSSM (turn signals and security module all in one!) - http://www.harleyshoptalk.net/forums/index.php?showtopic=29500. Things like security, tilt sensors and "module" can get annoyed pretty easily. See www.jpcycles.com/instructions/pdf/380-215.pdf for a procedure to reset the TSM / TSSM. I'm not saying this is part of what you need to do but it does show that that module might need a reset if you change things and resetting it reads like a video game cheat (Off, on, off, on, off, on, left, left, right, right, right, left, hold left, ignition on).

    There is a standard - http://www.gpo.gov/fdsys/pkg/CFR-1998-title49-vol5/xml/CFR-1998-title49-vol5-sec571-123.xml "Federal Motor Vehicle Safety Standard No. 123 standardizes
    motorcycle controls to minimize the risk of crashes resulting from operator errors in the use of controls." If a manufacturer doesn't follow it they can apply for a "Decision of Inconsequential Noncompliance" http://www.gpo.gov/fdsys/pkg/FR-2003-08-28/html/03-22041.htm
    #44
  5. Tripped1

    Tripped1 Likely Lost.

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    All well and good, completely besides the point though, there is only input and output, if you can make them match you can use whatever you want to switch it. Which means an adequate number of poles, no more no less.

    The mechanical means simply doesn't matter.

    and you certainly can flip it "on" both ways at worst you have to add a relay, but that is far from difficult work. A double throw/double pole can be wired to act independantly or with a common (such as pressing it down) that actives both sides. Its simply a matter of wiring.
    #45
  6. msells

    msells Been here awhile

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    So my point, again, is that the Japanese switches I am familiar with don't have the right number of poles to support "turning both ways at once". Here is a cartoon-ish wiring diagram that I believe is indicative of a typical Japanese turn signal switch. Let me know how you would wire this type of switch up and turn it "on" both ways to be able to engage the hazards:

    [​IMG]

    Same switch in an actual motorcycle wiring diagram:

    [​IMG]
    #46