Any wiring guru s around HUGE QUESTION 03 vt750dc Relocated the start button...


Any wiring guru's around? HUGE QUESTION!! 03 vt750dc. Relocated the start button and headlight switch. Head light is wired up fine and battery is charged. I had taken the wires on the old start button for the coils and the starter motor off and moved to the new button. Spliced the wires and it would start fine. Couple days later when I had time, soldered all of it together and now it don't start. Unwrapped all the electrical tape and cut wires back apart, spliced together again without soldering, and still won't start. Checked the ign start fuse, it good. This is where it gets weird. Checked power across the main 30a fuse and got nothing. Fuse looks just fine. Checked power at one of the wires on the other side of the fuse, and got power to it. ?? Yellow and red wire coming off the main fuse goes to starter and then start button. Black and white wire goes from coils to the kill switch and to the start button. Kill switch is wired together.

Why did it work just fine before I soldered the wires up, but now it won't? What am I missing? Did something get fried in the process and if so, what could it be? The bike won't even attempt to start as if the kill switch is flipped...

%d comments
  • . I understand why you did the twisted wire dry run but here's the thing. Twisted wires would have some resistance but would still let enough current through to operate relays etc. Soldering the wires would have made a better connection and allowed more current to flow and potentially cause damage. I would suggest you take a step or two back. Disconnect the new wiring and ensure you have power where it should be and repair any faults (if any). Then recheck all your wiring and reconnect it in stages. Hard to suggest much more without the bike with me and my multimeter.

  • I did cut off all solder, but still nothing. I am not getting power to the starter wire, or to the coils. The kill switch wires are wired together, and not even getting power there. When I get home again, I will post a pic of all the wires that got spliced to help with confusion.

    It doesn't help that I'm not sure when I should have power at the starter or coils

  • Power should be available at the solenoid battery side of the relay all the time (on the big bolt terminal). On the control wire on the solenoid power should only be there as you press the starter button. Power should be on one side of the starter button as soon as the ignition is on. Thus, as you press the starter power is fed to the solenoid (just a heavy duty electrically operated switch) which operates and passed the heavy current to the starter motor to turn it. One quick test you can do which alarms some people is with the ignition off short the two big terminals together - there will be sparks! and the motor should turn over so make sure it's in neutral. Next do the same with the ignition on and see if the motor starts and runs. Just as an aside, you are sure that the sidestand switch is functioning and hasn't got bent aren't you. Those switches are flimsy and do cause non-starting problems.

  • I will try that when I get home. Side stand is just fine and in neutral, literally nothing has changed since it was able to start besides soldering the wires. I'll let you know what I find out doing that. Are you referring to the battery terminals?

  • Battery terminals? - shit NO! Yes that would cause sparks indeedy! :-D No, I meant get a large open ended spanner (around 17mm should be big enough) and short the two fat terminals on the solenoid together. What this does is effectively take the place of of the solenoid. Warning: do NOT allow any part of the spanner to touch the frame, engine or other metal part as this will cause a dead short from your battery to earth. Hint, that would be bad ;-)

  • Key on. One with no power is going straight to starter

  • Yellow/red goes to starter solenoid and start button. Black/WHT goes to both coils, kill switch, and start button. No power to either by them selves, and nothing when they touch/button gets pressed

  • Kill switch wires also no power to them individually, or when spliced together

  • That's as it should be. If you short these two terminals does the starter turn?

  • Ok, so just short these? The sparks will be ok?

  • It does try to turn over yes

  • Yeah, loads of sparks but keep your spanner away from other metal bike parts

  • Does not start, gas tank is not on

  • OK great. so we know the starter is fine.

  • Wanna pm me?

  • Done