Broken down, needs help - spider problem?

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Tim

There are 6 grounding shunts on this bike that you need to locate and inspect for yourself. There is also a connector between the main harness and the forward sub harness which serves the faring forward of the frame. All 6 grounding shunts have black wires leading out of them. There are 2 other shunts which are not part of the grounding buss, one will have a black with whit stripe wire, the other will have black with blue strip wire.

Years ago when this first came to light, one of our forum members made a spreadsheet and labeled them in the following order...

#1 is located behind the left side panel under the seat, beneath the air box cover.

#2 and #3 are located under the fuel tank, to the left along side the frame next to where the fuel line plugs into the throttle body fuel injector rail. one of these has striped wires and are part of the low voltage electronics.

#4 is located under the fuel tank, to the left and forward of the cylinder head. This grounding shunt (spider) is the one that has the most reports of failure. This is the one that the Yamaha Recall Harness ties into; it's other end ties back into the main grounding wire at a large connector beneath the lower right fairing, in front of the battery.

#5 is located under the fuel tank, to the right and forward of the cylinder head. This one is the other striped wire, low voltage electronics shunt.

#6 is located down low in the left forward fairing near the left horn, in front of the accessory box. Gain access to this by removing the black inner panel next to the horn.

#7 is located just to the right and above the left headlight socket. Gain access to it by removing the left black upper dash panel.

#8 is located just to the left and above the right headlight socket. Gain access to it by removing the right black upper dash panel.

The other connector which sometimes gives grief is located beneath the left dash to the rear of the coolant filler cap. The easiest access is to remove the left lower faring panel. There are several large connectors in this area, find the sub harness and let it lead you to the proper one.

The ground shunt (spider) that your dealer most likely serviced was #4. These grounding shunts are daisy chained to this one shunt, as well as two other components. It's sixth wire leads from this, connecting the daisy chain back to the main ground wire deep within the wire harness; the main ground heavy wire leads from the voltage regulator to the battery negative terminal.

We have found that when the bike is factory fresh, the connector pins are clean and corrosion free. Given a year or three just having them exposed to the atmosphere will allow them to oxidize to the point of creating resistance. When there is electrical resistance you get heat, the more heat the more resistance you get. It will eventually become a thermal runaway and you will get scorching of the connector, annealing of the pin metal and worse case, melting of the wire insulation leading back into the main harness.

Since you retrieved the bike from the dealer service department, your job is to gain access to all these connectors to look for a burned pin. If/when you find it, you have a decision to make...

Take it back to the dealer service department for them to replace the whole wiring harness with a new, re-engineered one. This is also covered in the recall, if there is damage, it will be covered on Yamaha's dime.

Or

Fix it yourself. If the pin isn't too far damaged, you may have luck removing the black cap and re-inserting the shorting bar several times. The sliding contact action will self clean the oxidation from these pins. You should do that for ALL the connectors on the bike, and coat them with an anti-corrosion spray like CorrosionX or ACF 50, or inject a bit of Permatex dielectric grease into the female side of the connector. The idea is to break the corrosion and create a barrier from the oxygen in the air thereby inhibiting it's regrowth.

IF the pins are too far damaged, the easiest way is to remove the plastic connector from these pins, cut them off leaving the wires as long as possible, twist them together, insert them into a butt splice and crimp/solder them together. Then cover with tape or heat shrink.

Please note that when I designed my Grounding Harness, it was meant to prevent damage from occurring, not to fix an already damaged grounding shunt.

These are great machines, but they're designed and built by humans. The neat thing is that there are owners forums like this which bring together smart people who will share their ideas and experiences, and help each other out.

Good luck, I hope this helps.

Brodie

rolleyes.gif


 
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Wow! Thanks Brodie for such a detailed response. If we ever meet the beverages are on me.

I will do the work myself and hopefully it will go as planned. We'll see

Tim

 
I'm not trying to stomp on your thread, but a question just popped into my feeble brain. I've been into fjr's not even a year yet, so I'm no where near the knowledge level of some of the fine gentlemen in this forum that have years of feejer experience under their belts. Fully realizing that harness issues can stem from corrosion and/or faulty connectors, even under normal use, and there is certainly poorly designed stuff out there, but I'm wondering if at least some of these ground spider issues might have been helped along by user activity. What I mean to say, is that the factory engineers design these systems with a given current load in mind, and yes, I know from personal experience that engineers are human and by no means perfect, but could it be that adding accessories onto the bike that add to the current load drawn through these connectors might be causing them to heat up, corrode, and ultimately fail?

 
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The AWG of the bikes wiring is ridiculously small.

I measured the current on some legs of the bridge and my jaw dropped.

Some of the wires are around .8mm CSA, all my data is on the other computer.

All I do know is my mate had 9 amps through his new bypass loom I made for his bike.

You would be mad if you use the bikes wiring, hooking up a trigger relay isn't a problem.

 
Ok, so if I'm not mistaken, a .8 mm wire is about the same as a 20 ga. awg wire over here, which is good for 11 amps max iirc. 9 amps constant going through a wire like that, with connector pins being a certain weak link sure does seem to be pushing the envelope a bit. At that rate, it seems like just a matter time before bad things happen. Agreed, it sure seems like it'd be best to use aftermarket harnesses via trigger relays for accessories.

 
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The wire leading from the S4 grounding shunt to the large main ground path between the voltage regulator and battery is 1.0mm, sufficient to do the job, however there is little room for more current to flow. What starts the thermal runaway is the Sumitomo connector pins. When new there is no oxidation on the surface of the metal. Just exposed to the air oxidation forms with the resulting electrical resistance.

That's why many of us are a firm advocate of treating these connectors with some type of film to isolate it from the environment. My past two FJRs had been successfully treated with the Permetex dielectric tune up grease. My current FJR ('08 AE) got the ACF50 treatment right after I bought it early last year. Both are a little messy, for me the jury is still out how long the ACF50 will hold up without the need for reapplying it.

Dielectric tuneup grease is much easier to get.

By all means run a parallel system for all your electrical farkles, the only thing that should tie into the bikes wiring should be a handful of relays.

Brodie

🙂

 
Hi Tim, sorry to hear you are going through a spider hassle. I have been down this road twice with the 2006 I once owned. To make a very long story short, I feel Yamaha is still very sensitive to this issue. I take it your bike never had the recall performed. It also sounds like upon inspection damage was found. I believe the recall states that if damage is found on the harness, a new one will be installed per the recall. If no damage then the recall harness patch is installed. I would give Yamaha headquarters a call. Also, look for another dealer that you would trust with your bike. ( I know, they can be hard to find) Worth a phone call, sounds like you have a good case. Good luck with Yamaha, I hope they do what is right and install a new re designed harness in your bike.

 
That current was on the new bypass shunt circuit.

The wire leading from the S4 connector to the single point of the frame is 16 awg, 1.31 mm CSA.

That wire has the entire 12 volt neutral current of the bike passing through it. (all bar starter motor)

The reason for going "overboard" on wire size is to lower resistance to allow more current to flow and get it away from the spider circuit.

Most of the spider AWG are a mix of 16, 18 and 20, the wire that goes to the battery from the S4 connector has a conservative current measurement of 40 amps maybe up to 50.

I think the CCA of 16AWG is about 18 amps Vs 40 amps (50) running current ???? The only saving grace is the short wire lengths on the bike & not all are running at the one time.

Also remember to look up automotive tables, not household wiring, they are rated higher

Most of the time with burnt spiders it's thermal run-a-way due to poor pin contact, corrosion.

 
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Corrosion starts from the atmosphere acting on the connector. This spreads into the contact area, causing high resistance, leading to heat and burning.

This is a picture of one of my '06 spiders, shows corrosion just starting, but not quite where the electrical contact is.

(Click on image for larger view)



The heat in the contact can be sufficient to burn the copper of the wire fading the joint, leading to the erroneous observation that the wire isn't thick enough for its current (though, of course, adding extra electrical load could be more than the wire can safely carry).

Had the above spider been left, that corrosion would have caused a problem, but I caught it in time. Used some petroleum jelly (a Vaseline-like stuff), which held it in good stead at least until I sold the bike - picture taken at about 3 years old, bike sold a year later.

Other connectors can suffer, example is an indicator light connector, centre of the picture below:



It's well worth going through all the bike's connectors and putting anything moisture and/or air inhibiting in them. It doesn't have to be especially conductive or insulative, the connectors all slide to ensure a metal-to-metal contact area.

 
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