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Stella's Overly Complicated Wiring V2

Discussion in 'The Garage' started by DanielBlack, Dec 15, 2018.

  1. DanielBlack

    DanielBlack XS650 Junkie

    Hello Gents.

    I put about a year of daily urban commute on my 77D restomod since implementing a complete rewire according to my own specs, but all along I've been troubled by some bugs. Unreliable voltage readings on my dash voltmeter, big dips in the dash and running lights when the headlight turns on, etc. I was quite happy with the outcome of my relay logic controls, but I was equally embarrassed by my inattention to return paths and a few shortcuts in execution. Improvement was coming as soon as I got a round tuit.

    Well, a couple months ago when I got Stella going again after the hot summer for a commute or two, that round tuit showed up. On my way in, displayed voltage started dropping from it's usual low-13s (there's usually a 1-1.3V discrepancy) down to the low 11s. Coming home, displayed voltage was no higher than 10.4 or so. Taking a quick look below, I find the culprit. Burned Ace Hardware 1/4" spade connectors on a white rectifier feeds. Watching this gorgeous riding weather pass by is a round tuit indeed.

    Burned Rectifier Leads cropped.jpg

    This time around, I'm making a few improvements. Improved connectors, improved techniques, etc. Improved return paths, and a few improvements to the controls, too. Also, running things by this good forum before digging in. I think there's a pdf attached to this post.

    Edit: There is!

    The big feature of my wiring scheme is the use of basic SPDT relays in a variety of manner to utilize stock controls to fire an expanded range of lighting capability. My indicators are normally on running lights. Turning the stock "Lights" switch off makes them four-way hazards. The headlight turns off when in neutral.

    In the words of my wife who followed me home one day, the brake light modulator "is annoying as shit."

    In V1, all lights except the headlight were made LED. In V2, the headlight will be a gggGrzld-approved Broview.

    Ignition is a Boyer-Brandsen. Charging is the stock field-excited alternator with a modern regulator and rectifier.

    I know, it's all way too over complicated and the bike can easily be run with half this much copper. But what's the fun in that? I do welcome all your comments towards improving these ideas and helping chase the Gremlins out. Thank you.

    Attached Files:

    Last edited: Dec 15, 2018
  2. Mailman

    Mailman Hardly a Guru Top Contributor

    Daniel Black is back! I’m so happy to hear you are still giving Stella some love, with all the rest you have going on!
    Looking foward to following along with your retiring job and I want to see your new headlight in action!
    MaxPete and DanielBlack like this.
  3. MaxPete

    MaxPete Lucille, Betty & Demi - I suggest but THEY decide. XS650.com Supporter Top Contributor

    Daniel - the Wiring Man!!

    Folks - the mods that Daniel has accomplished on Stella are amazing. He has all sorts of additional functionality using simple components and his bike works great.
    DanielBlack, Mailman and TwoManyXS1Bs like this.
  4. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    You may want to reconsider the wiring logic to the neutral switch and relay. The voltage/current to the relay's coil is sufficient on initiation, but as soon as the relay pole swings, it's relying on the passthru current of the neutral bulb to continue the pull. And, the relay's coil reduces the current available to ground the neutral bulb...

    Screenshot_20181215-220408_Adobe Acrobat.jpg

    Also, may want to crack open one of the higher-current-carrying relays and inspect the contacts. See if vibration is affecting the contacts. Unless the relays are vibration isolated...
  5. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    May I offer this version:

    Stella's Wiring Diagram-Fix01.jpg
    DanielBlack likes this.
  6. DanielBlack

    DanielBlack XS650 Junkie

    Thanks 2M, you zeroed in on a interesting one. This logic (excluding the attempt at a self-latching circuit, which I now see won't work as I intend) is a holdover from V1 and gave me some trouble when first implemented. Your prompt makes it clear, thank you.

    With an LED bulb as the neutral indicator, the circuit wouldn't work at all. The bulb I had sourced was polarized and I hadn't thought to swap the hot/earth. Then I tried the stock incandescent. The relay would trip and hold reliably, but the bulb wouldn't light. Enough current to hold the relay, but as you note, not enough to light the bulb. With my headlight working, I called it good and went hunting for BBQ.

    I wonder, would a properly polarized LED work? Needing less current than a incandescent would it light even with the relay coil on the earthed side?

    As to the self-latching circuit, I like having no headlight on during starting and warmup. But I don't really like having the headlight dip as I shift through neutral from 1st to 2nd. And at long lights I like to relax sometimes, but that loses the headlight. A self-latching circuit that would hold the headlight after the first shift out of neutral is my goal. But the way I have it doesn't work with the normally closed setup I'm using here.

    Hmm...yes, reconcidering I am.
    Last edited: Dec 15, 2018
    Mailman and TwoManyXS1Bs like this.
  7. DanielBlack

    DanielBlack XS650 Junkie

    Definitely see the improved return paths there.

    Still thinking about the self-latching trick. Perhaps another trigger for the headlight that would be normally open.
    Last edited: Dec 15, 2018
  8. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    The self-latching stuff is usually done with DPDT.

    I recently acquired some instrument BA9s LEDs from Super Bright LEDs, in yellow, green, and white. Tested, and they are indeed polarity insensitive. And really bright.


    LEDs present a design challenge if used with other things in series. Typical Vf is 2.2v, the greens are Vf=3.3v. A current limiting resistor is normally used to keep the LED's current max at about 20ma, at its Vf. For an LED on a 12v circuit, typical limit resistors are 220-470 ohm.

    The typical aftermarket power relay has a coil of about 80 ohms, and needs to see certain voltage/currents for pull-in and hold.


    Those Super Bright LEDs already have current limiting resistors.

    Haha, another BBQ hunter.

    Watching with interest...
    Last edited: Dec 15, 2018
    peanut and DanielBlack like this.
  9. MaxPete

    MaxPete Lucille, Betty & Demi - I suggest but THEY decide. XS650.com Supporter Top Contributor

    A bit of a sidetrack Daniel - but I’ve recurring failures of the instrument bulbs on Lucille (a ‘76 Standard with the bayonet push and turn style sockets).

    Hav you had this problem and have you identified the correct LED replacement for those instrument bulbs?

  10. DanielBlack

    DanielBlack XS650 Junkie

    Pete, check out the bulbs 2M linked to above. I use the same vendor if not the same bulbs. Super bright indeed. Great for daytime use, almost too bright at night. Recall my turn signals are normally on runners, dash indicators as well. They are almost distractingly too bright, especially when I have the windshield fitted and they get reflected back at me.

    If I'm searching for those replacements I'm looking for the correct base, same color as the stock lens, and wide a field as possible to fill the stock reflector or lens. 90° is ok, but I'd prefer 120s. For the white instrument backlights I'd get the 3200K warm white.
  11. MaxPete

    MaxPete Lucille, Betty & Demi - I suggest but THEY decide. XS650.com Supporter Top Contributor

    Gotcha - done!

    Thanks 2M and DB!

    TwoManyXS1Bs likes this.
  12. gggGary

    gggGary Stop that! XS650.com Supporter Top Contributor

    someone should try red LEDs for the backlights.
    TwoManyXS1Bs and MaxPete like this.
  13. YamadudeXS650C

    YamadudeXS650C Central New York XS650 XS650.com Supporter Top Contributor

    Nice to see you Daniel !
    DanielBlack and MaxPete like this.
  14. Paul Sutton

    Paul Sutton Buckhorns on XV1000SE Top Contributor

    TM, thank you for the comment regarding relays and vibration. I am currently rewiring an XV using several relays to simplify things so must address the vibration issues.
    TwoManyXS1Bs, DanielBlack and MaxPete like this.
  15. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    Ok, I see. Not a problem with our early XSs, with a headlight switch.

    An interesting design challenge. On initiation, the headlight is off. Then, once the neutral switch opens, headlight comes on, and stays thataway, until bike shutoff. No connection to the alternator output routines. And, you'd prefer that the "headlight on" condition occurs with non-energised relay(s). Sort of the opposite of a latching circuit, an irreversible cutout...
    DanielBlack likes this.
  16. DanielBlack

    DanielBlack XS650 Junkie

    Yes, exactly!

    I guess I had the same feature with the 77 'Lights' switch, but I use that now for the four-way hazards. I could add a non-stock switch for those.
    TwoManyXS1Bs likes this.
  17. DanielBlack

    DanielBlack XS650 Junkie

    2M, your notes on vibration got me searching

    The relays I have are Panasonic automotive relays I sourced from cycleterminal.com.


    Found this data sheet that's more detailed than I currently understand.

    Attached Files:

  18. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    Those are really good relays. Same in my 28-year-old Ford. Indestructible. But still mounted on a vibration isolated panel. Your electrical demands are well below those ratings.

    Are you comfortable with Solid State transistors, like 2N3906?

    Might be able to cook-up a tiny lockout circuit that could be glued atop the relay...
    DanielBlack, gggGary and MaxPete like this.
  19. DanielBlack

    DanielBlack XS650 Junkie

    Haven't been introduced, but I'm game for learning about them. I have some rusty AV cable soldering experience and where that fails I have a motorcycle-riding, electronics service technician colleague/friend to call on for the close and delicate work.
    gggGary and MaxPete like this.
  20. TwoManyXS1Bs

    TwoManyXS1Bs BBQ Hunter Top Contributor

    Ok, gimme a few. I'll cook up something and post it...
    Paul Sutton, gggGary and DanielBlack like this.

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