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On reading of your problems the first thing I was going to ask you is, when the ignition wires and caps were replaced did you retain the original resistance values. The shop service manual would normally specify all of the appropriate resistance values as that is how you test the components integrity.
Can you mess with combinations of resistor plugs/wires and caps? <- Simple answer is yes, but electricity will always take the the easiest path to ground, so if that resistance is in the cap or plug, the wire is more likely to arc through the wires insulation and water is the perfect conduit for that. You could try adding some wire wrap or change out the ignition set again for something more stock.
 

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Discussion Starter · #62 ·
The plug caps are 5K ohm each and the plugs used have no extra resistance apparently.
The plug was replaced to one according to manual. NGK D8EA
For the plug caps i just bought new of the same that was there previously. It's 2x straight caps (NGK 8022) and 2x angled caps (NGK 8072) and i think that the correct stuff

I checked manual again but the only resistances it lists in relation to ignition is coil resistance

electricity will always take the the easiest path to ground
Yes that's right. Only thing that comes to mind is that the leads i used aren't great quality and the insulation isn't strong enough. That's why i think there could be arcing in spots where the leads are crossing and are really close to each other
I used 7mm silicone leads. I actually went ahead and ordered 8mm leads but i misread the description and carbon cored leads arrived, hence my question about resistance.
 

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Carbon core have resistance for sure. I'd be inclined to meter test the resistance of the whole thing from the coils to the plug electrode. View the running engine in darkness and you might be able to see exactly where the wires are arcing.

This is the kind of values I would expect your service manual to say:
Ignition coil resistance
Primary 2.6 – 3.2 Ω (20°C/68°F) –
Secondary with plug cap 17.3 – 22.8 kΩ (20°C/68°F) –
Secondary without plug cap 13.5 – 16.5 kΩ (20°C/68°F)
 

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Discussion Starter · #64 ·
I had another look, this time I took some time to investigate properly and took the tank off, and connected the fuel hose externally.

I checked the coil resistances using a multimeter and it all looks fine on that end.

I reinstalled the ignition leads making sure that the rubber pieces are all greased up and sealing properly.

Unfortunately the problem is still there but I have new findings:

When some water is sprayed on the ignition leads and plug caps, and i put my finger to the leads, i can feel some zapping.
Only happens when wet and it feels stronger when one finger touches the lead, and the other an engine casing which would make sense.
Engine runs rough but doesn't die.

I noticed the engine dies very quickly when there is enough water to pool around the spark plugs, when there is enough of it that it doesn't evaporate off of the hot engine quickly enough.

I will change to 8mm leads (currently have 7mm dia) in hopes that adding insulation makes it better.

But the fact that water standing around plugs makes it worse is confusing me. It's far from the spark when there, surrounded by plug body and engine casing which are both grounded.
 

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I think I would put some spiral wire wrap over the wires that seem to be leaking current the most. The engine really should still run even when it is practically submerged in water so something still isn't right.

Are you still running resistor type spark plugs? I'd be switching the plugs out as well to make sure it's not just a crack defect in the ceramic spark plug insulator. Brand new plugs is not a guarantee that they are good, I've seen plenty of NGK spark plugs DOA, usually when they are bought on sale and packaged in pairs.
 

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Discussion Starter · #66 ·
The spark plugs I am using are NGK D8EA which have no resistor, but the caps have 5K ohms of resistance.

I'll be sure to put in a new set of spark plugs too.
I am considering the Iridium DR8EIX out of desperation. It has 5Kohms resistance though so I don't know will that change anything.

I also forgot to add, when the ignition lines are wet and the bike starts to run really rough, but yet not rough enough to die, giving it even little throttle causes it to die immediately.
Not sure if that is relevant to ignition though?
 

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As engine speed increases so does the electrical power output from the alternator, so there is some relationship to potentially cause more arcing in the wrong places as engine speed increases, that combined with extra fuel and air could be causing it to flame out. If it's not revving up lots prior to stalling, increased voltage at the source is not the problem, it's just flaming out because of lost spark, poor spark or fuel/air issues.

Any success on comparing the heat of your header pipes? That might help track down the problem to either one or two cylinders. If it's one lazy cylinder you will be looking for problems that affect only one cylinder, if it is a pair and that pair relates to a shared component such as the coil, that will be helpful to trouble-shoot..

Arcing through All the wires would point to a wire, cap and electrics incompatibility problem.
Have you looked at it when it is running in darkness yet? You mightl see a nice lightning show under the fuel tank.

Iridium plugs are fine just as long as they don't protrude into the cylinder any further then the originals. I doubt the design difference will cure the issues but the plugs are worth a try.
 

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"Use of non-resistor plugs in vehicles that call for a resistor type can result in rough idling, high-rpm misfire, and abnormal combustion." <- Almost sounds like your problem
 

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Discussion Starter · #69 ·
If it's not revving up lots prior to stalling, increased voltage at the source is not the problem, it's just flaming out because of lost spark, poor spark or fuel/air issues.
It dies pretty much immediately even at tiny throttle input, the revs don't even climb. But all happening only when ignition area is wet. Dry is perfect.

Any success on comparing the heat of your header pipes?
Comparing the heat of header pipes also doesn't really do anything in this case because when dry its all fine, so they all get hot evenly, then i introduce the spray bottle and it all gets weird.

Have you looked at it when it is running in darkness yet?
I didn't try that yet, but i dont think there are visible sparks arcing. I think its more like the current is travelling through the water instead of arcing from one part to another.

Use of non-resistor plugs in vehicles that call for a resistor type can result in rough idling, high-rpm misfire, and abnormal combustion
The thing is the non resistor plugs that I use at the moment are per the manual. The bike is designed to run non resistor plugs and resistor caps. So with the iridium plugs i would be doubling the resistance. And again, all these issues are when wet. I think if there was a problem with plug resistance, it would happen in the dry as well
 

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All that points back to the wires.

Original ignition wire sets sometimes have an extra layer of insulation in places that need it, that's the same concept I was recommending the spiral wire wrap for. Spiral wrap is plastic cheap and easy to apply, handy stuff to keep in the tool box.
 

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Ireland :cool: must be damp to wet there all the time just like it is here, but maybe without the mosquitoes.

She's gotta run when it's wet or she won't be much use to you, if you can feel the current leaking through the wires you need better insulation. Dielectric grease is not a conductor so make sure you don't grease up the surfaces that need to conduct, that would exacerbate the problems.
 

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Discussion Starter · #72 ·
Original ignition wire sets sometimes have an extra layer of insulation in places that need it
Yes, i plan to put rubber tubing like fuel hoses in those places if need be.

She's gotta run when it's wet or she won't be much use to you
You're absolutely right. I got caught in the rain twice already and it just turned off when i stopped at a junction



So I did some research and ordered new leads.

Current leads are 7mm PVC copper core

I ordered:
7mm Tinned copper core made of Hypalon + new resistive caps
7mm graphite core made of silicone
8mm graphite core made of silicone

I could not find any 8mm copper core leads, surprisingly.

I ordered the 8mm leads just in case, but I think I will have to stick with 7mm because of the seals that to between the coil and coil caps have a 7mm opening in them.

If the Hypalon material tinned copper core doesn't make things better, I will try the graphite core as an experiment.

Data sheet says the resistivity of the graphite core leads is 16k ohm per meter so it would be anther 5K ohm per plug more or less. In that case I would also have to switch to non resistive plug caps to balance it out.

I saw pictures of the Dyna coils with Tyler leads and these also are graphite core, but come with caps integrated into the lead.

Current setup: copper core + resistor caps + non resistor plugs = 5K ohm

copper core + resistor caps + iridium plugs = 10K ohm
copper core + straight-through caps + iridium plugs = 5K ohm

graphite core + resistor caps + non resistor plugs= 10k ohm
graphite core + resistor caps + iridium plugs = 15k ohm
graphite per core + straight-through caps + non resistor plugs = 5K ohm
graphite per core + straight-through caps + iridium plugs = 10K ohm

Obviously its not standard and the system needs some resistance to prevent interference, but is adding a bit more resistance really such a big problem?
 

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From the sounds of it, you will have everything in hand to test any combination imaginable and just as long as you still have a bright blue spark at the plug you are good to go. The fatter wires are usually the result of a larger core, not necessarily a thicker insulation covering, that's probably why you are not finding large diameter wire with copper core.
 

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Discussion Starter · #74 ·
I had a go at the bike today and put on new copper core HT leads with new plug caps.

I also put rubber hoses over the new leads, to create a thicker barrier in places where the leads are close to the frame or are crossing each other.
The rubber hose diameter was not big enough so i cut it open along the length, and put it on with the opening facing towards the middle of the engine.
I then put zip-ties on both ends so they're held in place.

Not perfect, they should be larger diameter so they would not need splitting open, but its what I had at hand. Looks OK from the sides.

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The water bottle spray did nothing after this, so i got the garden hose out and put it in mist mode.
When there was loads of water around the spark plugs, the motor would slightly drop RPMs now and again but it was barely noticeable.

I would consider this job a success. So after this I didn't even bother testing the graphite core leads, and left the spark plugs the same. I'll put in the iridium ones at next service.

I also noticed that the fuel hoses are really perished. with visible cracks along. I am thinking about replacing those with transparent PVC tubing.
I read that PVC is not made to be used with petrol, but i left some in a tube for a week and nothing happened with it. Any opinions about that?
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