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I am doin a custom build on a 94 VN750 and im trying to figure out the bare minimums of the wiring harness. I am not going to run gauges, thermostats, or turn signals. I have some experience with a 454 LTD which is a similar harness. right now i have the ignition hooked up but nothing happens when i hit start, the solenoid doesnt click over but it will if the short it with a screwdriver. I have no power at the start switch, I think i have a bad fuse box? I have the following hooked up and the rest is not- ignition, CDI box, fuse box, rectifier, starter solenoid, coils & stator. I saw the post about testing the fuse box, I have battery voltage going in but not coming out of the 10pin connection. If thats bad i guess it would hinder spark because its not giving power to the CDI and coils?
 

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Sparky!!!
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took me a couple of days to work out all the kinks. But when I do it all over again to clean it up and make it look prety, it will take a couple of hours... I recomend buying several spools of various colored wire and building the harness from scratch, just re use the stock connectors to connect things like the JB, Igniter Box, and any other stock electrical item you are going to run.

one other thing I should mention is that I only used the ignighter box, all else has been scrapped to include the ignition switch, JB, RLU, and prety much every thing else you see missing

 

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I believe slim has done just that. Looks like he replaced the JB with a "fuse box" with 'always on' and 'acc. on' fuses, and replaced the JB relays with standard automotive type relays.
 

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Sparky!!!
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yes that is exactly what I did, you will also notice that you need a minimum of one diode for the neutral safety switch. I also added a relay for the ignition coils, so they will get a full 12.0-14.5V... one note on adding automotive relays and a fuse box, there isn't room any where on the bike to mount them, so I went with an "earshave" but kept the ears in place to hold my electrical goodies. the left ear houses my ignition switch, fuse box, relays, and diodes. The right side houses my R/R and my Ignigter Box.

One other thing I would do differently is make common hot and ground posts inside the "ears" to make things a lot cleaner, right now I have way to many wires running from the battery to the fuse box for no reason (they aren't shown in my schematic).
 

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Discussion Starter #8
that sounds like a lot more work than its worth... u eliminated the junction box but ended up adding more bulk? wuts the purpose?
 

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Slim............
1: Did you run both TCI ground wires though the diodes? ( stock wiring has a dedicated ground (B/Y) and one that goes through the safety switches (B/W to JB pin 14))

2: I don't believe the diode is necessary in your circuit. From what I can tell from the Clymer manual, the diodes keep the starter relay from back feeding the TCI along JB pin14. I can't see what purpose it serves in your circuit.....

3: I like your idea of running the coils directly off the battery for max power, but I think when I do mine I will power the TCI off the 'A' circuit of the ign. sw. and leave the coils as the only things off the 'coil relay.'

4: point 3 above makes me wonder if the R/W wire off the TCI even needs to be connected to the 'S' terminal at all? I believe it functions the same as a starter ballast in a car's ignition/start circuit....that is to provide more voltage to the coils while the starter motor is running. BUT, if the coils are connected directly to the battery via a big, fat wire....maybe that would be enough??

5: I have not tested any of these ideas, YET........... so there is an ever so slight chance I could be totally wrong :)
 

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Sparky!!!
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Slim............
1: Did you run both TCI ground wires though the diodes? ( stock wiring has a dedicated ground (B/Y) and one that goes through the safety switches (B/W to JB pin 14))I ran just the B/W through the Diodes, I tried every way I could think of to get rid of the diode, but the TCI wouldn't work with out it.. as soon as I would put it into gear the bike would die.

2: I don't believe the diode is necessary in your circuit. From what I can tell from the Clymer manual, the diodes keep the starter relay from back feeding the TCI along JB pin14. I can't see what purpose it serves in your circuit.....
Links back to point one
3: I like your idea of running the coils directly off the battery for max power, but I think when I do mine I will power the TCI off the 'A' circuit of the ign. sw. and leave the coils as the only things off the 'coil relay.'
Ther is nothing else being drawn off of the Ignition Coil Relay other than the TAC
The ACC side of my ignition switch is ACC only
4: point 3 above makes me wonder if the R/W wire off the TCI even needs to be connected to the 'S' terminal at all? I believe it functions the same as a starter ballast in a car's ignition/start circuit....that is to provide more voltage to the coils while the starter motor is running. BUT, if the coils are connected directly to the battery via a big, fat wire....maybe that would be enough??
the reason for the the r/w wire only goes to start for starting with the ignition switch, I no longer have the handle bar mounted push switch.

5: I have not tested any of these ideas, YET........... so there is an ever so slight chance I could be totally wrong :)
I hope this answers your question Dariv, Now onto Board917's question

that sounds like a lot more work than its worth... u eliminated the junction box but ended up adding more bulk? wuts the purpose?
The main reason was to get rid of the non replaceable relays and diodes inside the JB. The second reason is because I needed to add a couple of extra relays for added accessories, and didn't have a place to mount them. and third reason being is that I had to rebuild my carbs, so decided to do the "earshave" since I had to re-jet the carbs due to changing my exhaust any ways. And last reason is I had a bad wiring harness to begin with, so I had to Make a new one, and decided this was the easiest rout to go.
 

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Slim....................

1: That's odd about the diode. I don't get it..... I will see if I can get rid of it when I re-wire the bike.

3: It looks like you are powering the TCI unit along with the two coils off the 'coil relay.' I was going to power them separately.

4: I plan to replace the ignition switch with a relay fired by an RFID tag reader. (Sombra K9 alarm system) I'll be keeping the handlebar push button.
 

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Sparky!!!
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but JBs are pretty cheap, i just picked one up for $14.

anyone have a list of wire color and function?
Do you have a Kawasaki Service manual? if you look at the complete wring diagram it pretty well explains the wire colors and their functions coming out of the JB.

Here is a Color Coded version of the JB diagram, unfortunately it doesn't list functions. (It isn't 100% accurate, but really really close)


If you are a member of our sister site on Yahoo, then here is a link to the full Color Wire Schematic

You can also get all the wireing diagrams HERE Just scroll down to the bottom of the page

and http://www.tocmanufacturing.com/Files for Download/VN750 Manual and Parts.pdf is the full Kawasaki Service Manual for free thanks to our friends at TOC
 

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Sparky!!!
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Slim....................

1: That's odd about the diode. I don't get it..... I will see if I can get rid of it when I re-wire the bike.
if you were to wire the b/w to ground it will work, but I wanted to keep the neutral switch so that the bike can't start unless in neutral.

3: It looks like you are powering the TCI unit along with the two coils off the 'coil relay.' I was going to power them separately.
I marked the TCI wrong, it is getting power from looks to be the S terminal of the Ignition switch, but in reality it comes from the ignition side of the ignition switch. the Red wire that the coil relay fires on is actually redundant, the TCI actually sends power to the coils on the Red wire, then sends a pulse along the black and green wires. theoretically you could cut the coil wire between the TCI and the Relay, I left it in place as a failsafe, to keep the bike running in the event a relay failed.
4: I plan to replace the ignition switch with a relay fired by an RFID tag reader. (Sombra K9 alarm system) I'll be keeping the handlebar push button.
I think with the K9 alarm you should be good... just unplug the stock ignition switch, and wire every thing up the same way to the K9 circuit board or what ever.
 
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