1. Some members were not receiving emails sent from XJbikes.com. For example: "Forgot your password?" function to reset your password would not send email to some members. I believe this has been resolved now. Please use "Contact Us" form (see page footer link) if you still have email issues. SnoSheriff

    Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

Question on complete re-wire of XJ750

Discussion in 'XJ Modifications' started by Dr. Awesome, Apr 8, 2017.

  1. Dr. Awesome

    Dr. Awesome New Member

    Messages:
    29
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    MN
    So I'm still working on my build thread... but I'm completely re-wiring my '82 XJ750 Maxim due to massive component replacement and electrical issues I didn't want to troubleshoot. I have laid it all out, but there is one aspect I'm not exactly sure about. Right now I have the majority of the power (ignition, signal, and headlight) running through the main ignition relay. When I start the bike I'm a little concerned that the voltage will drop enough to drop out the relay, killing power to the IC/coils, and I'll never get it to start! The pickup voltage is pretty low on the relay, but it's till something to I'm worried about. Has anyone had electrical experience on something like this? All of the components are close together with minimal wiring runs, using 16 ga wire mainly except for larger gauge wire to the battery/regulator.

    Check out the wiring drawing I laid out, if you have any input I'd love to hear it!

    Wiring Diagram:
    My Wiring.png

    Harness layout:
    Harness.png
     
  2. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,097
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    the drop out of a relay is usually lower than the pickup, maybe a whole volt.
    if you're doing a custom wire job, think about a headlight master switch. it's handy to have while you're working on the bike with the key on. the battery will thank you.
    if the relay dropout is a problem, that switch will be real handy.
     
  3. XJ550H

    XJ550H Well-Known Member Premium Member

    Messages:
    13,199
    Likes Received:
    3,861
    Trophy Points:
    113
    Location:
    Great North Woods
    are you using the oem controls on the handle bars?
    removing the atari box?
    key relay rated for what amps ?
    use oem key switch yours should have 2 pig tails.
    flasher switch needs to be a 3 position switch on-off-on
    poor way to use a kill switch. it will shut down all power to bike that is what the oem ignition switch is for. use kill switch to disable tci box only
    missing tail light and plate light. which run off the main fuse not head or signal
    start switch through clutch switch??
    loose the clutch switch
    learn to find neutral or always pull in the clutch when starting which is a good pratice anyways.

    follow the min wiring diagram and then add blinkers.
     

    Attached Files:

    Last edited: Apr 8, 2017
  4. Dr. Awesome

    Dr. Awesome New Member

    Messages:
    29
    Likes Received:
    1
    Trophy Points:
    3
    Location:
    MN
    Thanks for the input, I'm not using OEM controls (they were broken) but am using older Yamaha controls, just not sure off of what. Atari box is gone, the only electrical on there is what you see. The OEM ignition is gone, I have a standard 3-position one I mounted under the seat (center control box). The relay is a 30/40A relay and the flasher switch is only shown that way because I had limited choices in the program I was using to organize it all.

    I'll add the running/license light, guess I overlooked that circuit, I suppose it is good to be seen when you are riding... I was thinking of adding the headlight cutoff, but the headlight is LED so it takes much less power than the regular one, so that is still up in the air.

    The only reason I have the clutch switch on the starter switch is because neutral is impossible to get unless its rolling and I'm not the primary rider (it's for my Dad and his brothers/sisters) so it's a fail-safe for them since I don't know their skill level and I'd rather force the habit on them. Worst case, it's an easy bypass if it fails and you won't notice it otherwise.

    The only question I have is would you really want your IC power going all the way up through your kill switch and back? If you are firing the ICs through there I would expect it would add unnecessary losses, so I think you would want it as short of a path to the battery as possible. I have seen problems with that posted for other bikes, but not sure if it's a concern on ours. I might make it a dedicated relay for the IC and add it to the control box.
     
  5. XJ550H

    XJ550H Well-Known Member Premium Member

    Messages:
    13,199
    Likes Received:
    3,861
    Trophy Points:
    113
    Location:
    Great North Woods
    thats how yamaha does it up to the kill switch then to the tci box through a relay.
    if you leave the tci powered up with the motor not running the tci fires after about a minute you can get quite the back fire

    look in this thread I posted a photo that shows the way it is on a 550
    I Maxim xj550 1981 Help Me Please

    engine stop switch is powered from fuse then runs to coils and tci.

    if you pull over you will not have any lights at night if you hit your kill switch. if you need to do work on the electrics you risk a back fire .

    I would add a neutral light so they can learn to find it. the neutral switch is what makes the connection to ground run a wire to a bulb then to voltage and you have a light.
    I would also add an oil light so you know when your low on oil.
    if you add a resistor and rectifier diode to isolate it from the oil switch you can hook it to the ground side of the solinoid . that way when you start the bike the light comes on when you push the starter button confirming the bulb works.
     
    Last edited: Apr 8, 2017

Share This Page