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Discussion Starter · #1 ·
Ok, so it's not a fighter (I have a buell xb that will be), but I recently hard tailed an 81 kz440 and bobbed it. I just stuck all the factory wiring on the side of the hard tail in an ammo can. I can read a schematic ok, and I know how to solder and wire, my hang up is what the hell to keep? I want my wiring as simple as possible and I just have no idea what I can ditch and what I can't. I don't have a clue what all the miscilaneaous resistors and fuses do. I just want a guide or some information.
Here's the culprit...

 

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Bitches love Fighters
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you can remove the turn signals, all the wiring including the turn signal control box and the turn signal flasher. the horn and all the wiring. and the left hand control. youll need to wire up a 3 pole switch for high and low beam but we can figure that out later. it also looks like you can get rid of the distance sensor as it only links to the turn signal auto cancel. and you can get rid of the gauge cluster and just put a small bicycle speedo on it if you even want one.

obviously test the bike out before you make anything permanent. just un plug those things and see if it still starts and runs
 
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The easiest thing is to start from scratch, theres two seperate systems runnin & charging then lights etc

My way is to fit the ignitor, coils etc basically anything it need to run & string some wires to sort that out, i use a combo of haynes & the chop wiring diagrams to do this & its pretty simple Theres a good chop diagram here http://www.thefont.info/contents.htm

Then i wire the other circuits such as lights horn etc using the same method eg fit it wire it then check it

You will find that theres a tendancy to use at least 3 wires in the stock harness where 1 will work just as well so once you have it right there will have used a hell of a lot less wires than in the stock loom even if you fit everything the original bike had from new

The chop i built for the mrs has less than 20 wires in all & all thats missing over stock is indicators, one thing i did find out the hard way is dont use connectors on the alternator output wiring they will burn out pretty quick, just leave a bit of spare wire so you can cut & re solder if you ever need to.
 

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Discussion Starter · #5 ·
it depends. do you want turn signals or a horn?
Well initially I was running rear turn signals in case a cop was ever behind me. But in all honesty I don't think they'd care, and I don't give a shit if they do. I have removed the horn and replaced the left control with an enduro control. The bike is electronic ignition.

I have seen a few bobber wiring diagrams, I guess I just need to be able to identify different components. The thing with the aluminum fins, I believe it is a rectifier, I hear I need that but I dont know what it does.
 

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Discussion Starter · #6 ·
You will find that theres a tendancy to use at least 3 wires in the stock harness where 1 will work just as well so once you have it right there will have used a hell of a lot less wires than in the stock loom even if you fit everything the original bike had from new.
Yes, the factory harness has wires going everywhere. That is what has stopped me from experimenting and unplugging stuff. I dont know what else may be affected. There are tones of wires tied into other wires.

Basically I just want the thing to run and have a headlight and brake light. I was even thinking about ditching the key and going with a toggle switch for power and e start.

I like making things simple and sparce. I would love for the bike to run on as few as wires as possible.
 
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Should be reasonably easy once you know what you want & need but i do suggest you keep your original harness intact incase you mess up, at least you can still run it up then

RE the box with fins :)
The rectifier does exactly what is says rectifies :) when the engine is running the alternator throws out AC (alternating current) while the rest of the electrical system uses DC (direct current) so the rectifier changes the current from AC to DC

Its probably also the regulator, this part regulates the charge to the battery so that it does not overcharge, any excess current not needed by the bike is lost through the regulator by converting to heat, hence the fins

Most bikes of this era have a combined regulator & rectifier commonly shortened to reg/rec but some older models have seperate ones

Hope it helps :)
 

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Discussion Starter · #8 ·
That does help. I need to find a schematic that says what wires need to go where. Where the relay goes, how the switches hook, making sure the ignition has power and so on
 
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Once you figure out what wires do what on a wiring diagram & relate it to the bits you need on your bike you should be able to figure it out from the link i posted above
 

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It looks like that bike has electric start, so that box is a combination regulator/rectifier. If you don't have a battery anymore, you can replace it with a generic AC regulator and power the head/tail off AC (directly wiring it to the stator will blow bulbs every 5 minutes from too much voltage). It was fairly common for there to be both AC and DC outputs, the DC exclusively being used to recharge the battery.

The only thing you NEED from the stock wiring is the cdi box. Keep that and it's hookups to the trigger and ignition coil. Literally everything else can be tossed. For projects like this to me it's easier to start over and just wire the basics rather than try to chop up and sort out the stock harness. Note the 3 wires coming from the case for the stator. Get a generic r/r off ebay- literally any will work. Most have standard spade connectors. I bought a used zx14 r/r for like $20, and old 80's r/r boxes are not very reliable. Plug the 3 wires from the stator into the AC side, ground it, then you have a single +14v DC output for lights/battery. Get a generic kill switch (normally open), connect 1 wire to ground and the other to the coil trigger. Or a normally closed and put it inline with the trigger wire to the coil. If you want e-start, keep the starter solenoid and get another normally open pushbutton on the handlebar, which supplies +12v to the solenoid when pushed.

Some basic wiring for head/tail/brake, kill switch, and starter if you want. Bare minimum.
 

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Discussion Starter · #11 ·
Thanks man, It was just overwhelming looking at the stock harness. I had a bike rally I wanted to go to over the summer, so I just stuffed all the wires in the ammo can. Yes my plan is to start from scratch, with just a head light and tail light. Probably not even a push button start, just like a boat ignition (waterproof) and a kill switch.

I know the battery has wires everywhere, the main ones I was concerned with are to the starter solenoid and the ignition and charging system. I gotta get ahold of a factory schematic so I know how the charging system and coil pack gets wired. So I'll pick up a new solenoid just because, a new rectifier from a newer bike? And a fuse block?

Also, does anyone know a quality wire that has good color combos? Not just a spool of red and black from autozone?
 

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Discussion Starter · #12 ·
So there is a black plastic box with like 3 or 4 wires going into it and a resin filled back, what's that and what's it do?

There are also other silver cylinders other than the starter solenoid, what could those be and what do they do?
 

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My guess the black potted box is the CDI unit. One of the wires goes to the ignition coil, others go to the trigger coil that powers it.

Charging systems are stupid simple. You have three wires from the stator which are unregulated AC. These plug into the regulator/rectifier. Order doesn't matter, it's AC. The R/R has a + and - output, which is now DC regulated to about 14.5v. Stick those on the battery- that's really all there is to it.

Ignition....you have one (possibly two) trigger coils which are outside the flywheel, the stator is inside it. There's a spot on the flywheel that corresponds to maximum ignition advance timing. At this time it generates a pulse of power to the CDI box. Depending on current RPM/ frequency of the pulses, it calculates how much delay on a preset scale to set timing advance. At idle it adds a brief delay before the Capacitor Discharges to the Ignition coil. At full RPM there is little to no delay to give more advance. This is also quite simple, you can usually just match wire colors. Most older stuff just has bullet connectors between everything.

Electric start. Again, real easy. High current wire (6ga wire is common stock) from + battery to one side of the solenoid, doesn't matter which. High current wire from other side to the post on the starter, it's grounded through it's mount to the engine. There are usually two small terminals on the solenoid, when +12v DC is supplied it closes the circuit, which will activate the starter. Like r/r's these are very generic, the only variant is size/shape, they all work the same. You need some kind of momentary switch on this solenoid, either a push button or wired to the "start" output of a key switch if you want a car style ignition.
 

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Discussion Starter · #15 ·
Wow, that's amazing. Thanks fellas, I had most of those things assumed correctly, through guessing and without all the technical info.

I'll take pics of the other stuff, it's probably turn signal relays or whatever, but now I just want to lean and understand.
 

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Discussion Starter · #16 ·
Alright, it warmed up so I got some pics. Here are the pieces that I have no idea what they are. I did locate the ignition box and coil, they are under the tank. I recognize the reg/rect, starter soleniod, turn signal box (resin back), and fuse box. Here are some components I don't recognize:
This may just be a connector, not sure?

This is ?

This seems resin filled, not sure?

Another

And this is the ignition box
 
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Hello mate the first pic is a fuse holder, you should be able to pop it out of the rubber & open it up, i would guess this is your main fuse & it looks like theres a spare in the rubber

The second is your flasher unit, you can bin this if you dont use indicators

The third i would guess is a relay which could be for any number of things, hopefully someone will be along shortly to enlighten us on this one

I hope that helps a little !
 

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Discussion Starter · #18 ·
Thanks man. I'm up in the air about using signals or not. I'm sure if I sell it the new buyer would want signals.
 

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Most states do not require motorcycles older than the early 80's to have indicators. Bike inspections are a joke, if it has wheels and rolls most shops will put a sticker on it (aside from dealerships that tend to be more strict) so don't worry about that. If you were strictly by the book, probably 90% of the bikes on the road would not pass inspection.

With the bike chopped/modified as it is already, I wouldn't be worrying about resale value. That said, personally I think blinkers are a good idea for your own safety, you don't have to take hands off the bars, and I bet 95% of drivers have no idea what hand signals are when most don't know how to open the hood. I'd stick with 23w incandescents, DOT brightness, the cheap LED ones are so dim as to be pointless anyway, and good bright LED blinkers are pricey. Incandescent ones are cheap and you don't have to mess around with resistors and relays to get them to work properly on an older bike.
 

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Discussion Starter · #20 ·
So being this is a street fighter forum, how do you think a thread with the build pics of this bobber go over?
 
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