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1Back to top Go down   Basic Bike function Wiring Harness Empty Basic Bike function Wiring Harness on Thu Sep 05, 2019 8:18 pm

lechicho55

lechicho55
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I am turning my k100 into a cafe race and things are going well, but I am about to start the wiring.  I have the old harness completely removed.  I will be installing the moto gadget m unit for the blinkers, lights, speedo etc, so I just need the harness for the basic functions of the bike, alternator, starter, radiator fan etc.  The harness seems pretty confusing although I am a novice at it.  If anyone has any info on what I can eliminate or an easy way to eliminate wires and relays, I would really appreciate the help.

    

2Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 3:49 am

chris846

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Are you keeping the OE switchgear, including the ignition switch & brake & clutch switches? If so it makes sense to keep the old harness. The only 'relay' you'd be losing is the bulb monitoring unit.

If you're going mediaeval, it's possible to make a loom just for the fuel injection (it actually already exists), plus a loom for the ignition.

Best thing is to get your loom on the table, and study that wiring diagram. It gets quite straightforward if you break it down into the different functions. Cup of coffee time.


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The Longest Lunch
    

3Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 3:59 am

Laitch

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@chris846 wrote:Best thing is to get your loom on the table, and study that wiring diagram. It gets quite straightforward if you break it down into the different functions. Cup of coffee time.
That about sums it up. An added benefit is that you won't be a novice when you've successfully finished.

Have you seen this? Click on CC in the menu for subtitles if you need them.


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1995 K75 73,000 miles
Basic Bike function Wiring Harness Usa-lo10
    

4Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 4:24 am

lechicho55

lechicho55
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@chris846 wrote:Are you keeping the OE switchgear, including the ignition switch & brake & clutch switches? If so it makes sense to keep the old harness. The only 'relay' you'd be losing is the bulb monitoring unit.

If you're going mediaeval, it's possible to make a loom just for the fuel injection (it actually already exists), plus a loom for the ignition.

Best thing is to get your loom on the table, and study that wiring diagram. It gets quite straightforward if you break it down into the different functions. Cup of coffee time.
I am planning on replacing all oem controls, headlight, rearsets, speedo and use the moto gadget keyless ignition.  IT sounds like i just need the fuel injection loom?  Then I can get rid of the whole black box of wires and fuses and whatever else is in there.

    

5Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 4:27 am

lechicho55

lechicho55
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@Laitch wrote:
@chris846 wrote:Best thing is to get your loom on the table, and study that wiring diagram. It gets quite straightforward if you break it down into the different functions. Cup of coffee time.
That about sums it up. An added benefit is that you won't be a novice when you've successfully finished.

Have you seen this? Click on CC in the menu for subtitles if you need them.
I have not seen this before  It looks like it should make things much more simple, well in theory anyway.  I hope to get it figured out without taking the bike anywhere to get it fixed.

    

6Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 5:59 am

chris846

chris846
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"I am planning on replacing all oem controls, headlight, rearsets, speedo and use the moto gadget keyless ignition.  IT sounds like i just need the fuel injection loom?  Then I can get rid of the whole black box of wires and fuses and whatever else is in there."

Okay, you'll still need the starter relay, plus the fuel injection relay and the load shed relay. You'll also need some fuses. There's a fan control module in there too, which you'll need to get the temp control sensor to work the fan (it's kind of a relay plus). So that's 5 doohickeys that you'll have to retain.

I'd leave the motogadget thing to one side for starters, and concentrate on the engine circuits. The K100's engine management is kind of in two halves - the ignition side (module, coils/plugs, hall sensor) and the FI side (module, injectors, AFM, throttle position sensor, coolant temp sensor). Of these two halves, it's the ignition side that runs the show, and it kind of gets to veto what's happening by controlling the ground side of the FI relay coil (in case you over rev it - it just kills the whole FI, no subtlelty whatsoever) and the starter relay coil (once the engine fires/in case you keep the starter button pressed when the engine is running).

The ignition side talks to the FI (basically tells it to fire the injectors) via just one wire: 0.5mm Yellow/Red. That's it.

You could approach this by making two harnesses. The FI already sits by itself with its own harness anyway - a 4-way connector is all that connects it to the rest of the bike/main harness. The 4 wires are 2.5 GnRo (that's green and red in Deutsch - you'll need to brush up your germanspeak anyway) which is just the main 12v supply from the FI relay, 0.5 ViGn which is a resistance-to-ground signal from the bilateral temp sensor (for the fan control module), 0.5 GeRo which is the aforementioned signal from the ignition module, and 0.5 SwGe which is the switched 12v from the starter button (this probs tells the FI module to up the squirts on startup)

See, it's already getting easy!

The headscratcher might be the black/green wires that seem to get all over the place like knotweed roots. This circuit is for the clutch switch/neutral light/start button thingy. It has been the subject of many forum questions/threads from special builders. I'll let you get to grips with that one by yourself! (I wire my bikes without it, and just never press the starter without pulling the clutch in!)

The load shed circuit is there just to switch off the headlamp and horn whilst the starter is pressed. Again, if you can can develop the ability to do this yourself, then you can do away with it. If you're a novice to bike wiring, then here's a tip: the load shed relay coil is earthed via the windings of the starter motor - when the motor is running, the windings are at 12v, so the load shed relay coil doesn't operate.

Another circuit you might decide you can live without is the parking light circuit. Because there's a facility on the OE bike to have the parking lights on just via the ignition switch, there's an enormous amount of additional (mostly grey) wiring for this. Get rid of!

I have a chart of wire colours/functions somewhere that I'll see if I can post. It helps troubleshooting.

What you don't want, is anything to do with this guy:
Basic Bike function Wiring Harness Mummy11



Last edited by chris846 on Fri Sep 06, 2019 6:19 am; edited 3 times in total (Reason for editing : font size - what? / fan control wiring/forgot the mummy)


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7Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 6:58 am

chris846

chris846
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Here y'go

These are just my own notes, my goofs, my mistakes. I'd be amazed if it were perfect, but it should help you get to grips with your loom (a man needs to get to grips with his loom).

Basic Bike function Wiring Harness 00121
Basic Bike function Wiring Harness 00218
Basic Bike function Wiring Harness 00417
Basic Bike function Wiring Harness 00615


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The Longest Lunch
    

8Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 7:41 am

92KK 84WW Olaf

92KK 84WW Olaf
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One small thing.

The post does not mention2 or 4v engine.

MAF [air flow meter] in the air filter box on the 2 v engine if it s a2v K100......what happens to that and its wiring....?


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 98,780 miles
1983 K100RS 0011171 Fricka 29,495 miles Damn K Pox Its a Bat outta Hell No 32,600 miles
    

9Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 7:55 am

chris846

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‘Pologies, I referred to the MAF as AFM (airflow meter) It connects directly to the Jetronic loom, nothing else.


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10Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 8:10 am

chris846

chris846
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I’m in the middle of this job right now, so here’s the jetronic/fuel injection loom. Clockwise from left you’ve got connectors for AFM, temp sensor, 3 injectors (it’s a 75) TPS and ECU. The small connector in the middle is its connection to the main harness/bike. All the jetronic needs is power, a signal from the start button, and a signal from the ignition module. The fourth wire in the connector is actually an output from the temp sensor to the fan control module (the bike’ll run fine without it) the jetronic is almost a stand-alone - it sorts its own fuelling out.Basic Bike function Wiring Harness 79c50410Basic Bike function Wiring Harness 79c50410



Last edited by chris846 on Fri Sep 06, 2019 10:14 am; edited 2 times in total


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11Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 8:32 am

chris846

chris846
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Here’s the other half of things - the ignition module loom (which is part of the main harness) The module plug is at the bottom of the pic, and the Hall sensor connector sticks out of it. The connector at the top is where the Jetronic joins up (and you can see the yellow/red wire that the ignition module talks via to the jetronic) There are ten wires disappearing off to the right into the main loom. Vi/Gn (from the jetronic plug) - temp sensor output to fan module. Two Sw/Bl wires - one to fire coil 1, and a duplicate to drive the tacho. Sw/Gn and Sw/Ro are the two wires to fire coils 2 & 3. Gn/Ge is 12v from the ignition switch, via the kill switch, to operate the whole thing. Ge/Br is for the ignition module to supply ground to the FI relay, if it feels like it. And Br/Ro is the same for the starter relay coil.  Sw/Ge is the signal to the module from the starter button. Simples!Basic Bike function Wiring Harness E3a55c10



Last edited by chris846 on Fri Sep 06, 2019 10:17 am; edited 1 time in total


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The Longest Lunch
    

12Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 8:45 am

92KK 84WW Olaf

92KK 84WW Olaf
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@chris846 wrote:‘Pologies, I referred to the MAF as AFM (airflow meter) It connects directly to the Jetronic loom, nothing else.

Teach me to read the small print...you had mentioned it. Just flagging though that it normally has to be kept on the 2v.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 98,780 miles
1983 K100RS 0011171 Fricka 29,495 miles Damn K Pox Its a Bat outta Hell No 32,600 miles
    

13Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 8:57 am

chris846

chris846
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Dunno what this shit is for though!
Basic Bike function Wiring Harness Cf737f10


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14Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Fri Sep 06, 2019 10:37 am

chris846

chris846
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Maybe you've previously run the bike as standard. If so did the fan come on often, or ever at all? On the naked Ks there's plenty of breeze around things, and if you're stripping it even further for your cafe racer, then you might get away without a fan (dunno what the temps are like in N Dakota). I have a cafe racer K100 and the fan never comes on on that. Also, the fan never comes on on my K75, but that's because I didn't bother putting one on, based on my experience with the K100. Main thing I suppose is the climate where you are, and whether you anticipate sitting for hours in city traffic (or cutting through like a proper cafe racer should!) If you forgo the fan, then you can leave out that massive fan control module, plus a few yards of wiring. The bike will look even more stripped down too. Just a thought, it is possible.

As is evident from my ramblings above, it is possible to simplify things by eschewing some of the ignition module's control - just wire the starter relay and FI relay coils straight down to ground. Doesn't sound much, but it's surprising how much it will simplify things. You will lose the over-revving fuel cut out though (although the ignition retard at high revs will still operate). Likewise you'll also be able to mash your starter motor, if you really want to.


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15Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Sat Sep 07, 2019 4:30 am

lechicho55

lechicho55
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@92KK 84WW Olaf wrote:One small thing.

The post does not mention2 or 4v engine.

MAF [air flow meter] in the air filter box on the 2 v engine if it s a2v K100......what happens to that and its wiring....?
Its the 2v as its an oldy.    I forget there is a 4v

    

16Back to top Go down   Basic Bike function Wiring Harness Empty Re: Basic Bike function Wiring Harness on Sat Sep 07, 2019 4:34 am

lechicho55

lechicho55
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@chris846 wrote:I’m in the middle of this job right now, so here’s the jetronic/fuel injection loom. Clockwise from left you’ve got connectors for AFM, temp sensor, 3 injectors (it’s a 75) TPS and ECU. The small connector in the middle is its connection to the main harness/bike. All the jetronic needs is power, a signal from the start button, and a signal from the ignition module. The fourth wire in the connector is actually an output from the temp sensor to the fan control module (the bike’ll run fine without it) the jetronic is almost a stand-alone - it sorts its own fuelling out.Basic Bike function Wiring Harness 79c50410Basic Bike function Wiring Harness 79c50410
Yep.  I have the harness on the table and this was about the only thing I could figure out.  I wish it was all that simple.  Maybe it will be if I just take my time and slowly figure it out.  Actually I am just going to put the whole harness back on the bike for now as I don't have the m unit yet anyway since I just need the bike back together for a bit.

    

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