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SPARK PLUG WIRE RESISTANCE ???

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Old 08-31-2024, 11:25 AM
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Default SPARK PLUG WIRE RESISTANCE ???

Hello,

Having a Dyna 06, I just measured the resistance in my sparkplug wires, and reached astonishing results. I have googled on what is normal and it is said to be 10-12 Kohm/feet. 11 Kohm/feet will be 0.97 Kohm/inch and I have used this as a reference.

I wonder if someone here has any experience from checking your plug wires

Please see the strange results below:



It seems to me that the original wires are pretty much normal, but that the wires I bought from the dealer, which sit on the bike now, are not.

So what about that it must be stock wires for the ION-system to work, when the resistance can differ so much in stock wires? Or are both the 2017-wires to be considered as damaged?

It would be great if someone could shed some light over this.

Thanks a lot








 

Last edited by OakMountainRider; 08-31-2024 at 02:55 PM.
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Old 09-01-2024, 05:40 AM
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It would be great if someone here would comment on why one Harley Davidson stock rear plug wire can have six times higher resistance than another.

Many times I read about keeping to stock wires because of the function of the ION-system, which would be disturbed if other wires than stock were used. From that one would assume that Harley kept to some kind of resistance standard in their plug wires. Apparently this is not the case at all.

So now I am thinking of switching the ION-system off and then go with whatever plugs and wires I like, like IRDIUM plugs and real fat low resistance wires.

 
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Old 09-01-2024, 07:16 AM
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I have some new wires for an 07 Dyna.




I bought bought two sets when I replaced my plug wires and there is some variation. The set I installed measured 4.1k for the short one and 4.3k for the long one. The Fat Screamin Eagle wires measured 4.6k for the long one and 1875 for the short one.

I ran with knock control disabled for a while. It took one bad tank of gas on a hot day to change my mind about that.
 
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Old 09-01-2024, 07:41 AM
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carbon wires can range quite a bit. there can be diff mfg and diff materials and can have damaged core. one reason they need to be wiggle tested.
you can go spiral core and get the best of both worlds. ion sense is just a piggy back on the main strike and the ecu looks for the amount of current so if the wires are running the machine, ion will work.
it will also work over a wide band of resistance. at high tension, the electricity travels on the outside of the wire. fat wires are just more insulation for looks.
if it would not be for electronics, copper core wire would still be around.
 
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Old 09-01-2024, 07:59 AM
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Johannes, only as a suggestion, but I would get an OEM set. Just like Harley's branded plugs, they probably aren't made by Harley but are spect made with lower resistance then what you see in the auto world.

Your Harley has a ION spark detection system that stops pinging from damaging engine.

Google how does ION spark knock detection work


 

Last edited by Jackie Paper; 09-01-2024 at 08:04 AM.
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Old 09-01-2024, 08:31 AM
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[QUOTE So now I am thinking of switching the ION-system off and then go with whatever plugs and wires I like, like IRDIUM plugs and real fat low resistance wires.[/QUOTE]

SO, how would you go about shutting the ION sensing OFF?
 
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Old 09-01-2024, 09:13 AM
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Originally Posted by Rusty Springs
I have some new wires for an 07 Dyna.




I bought bought two sets when I replaced my plug wires and there is some variation. The set I installed measured 4.1k for the short one and 4.3k for the long one. The Fat Screamin Eagle wires measured 4.6k for the long one and 1875 for the short one.

I ran with knock control disabled for a while. It took one bad tank of gas on a hot day to change my mind about that.
Oki, thanks. Good to know. Right now I do not receive any knockcounts, so I thought I could as well turn it off. But bad gas on a hot day is not good off course, and then it is good if knock control is on.
 

Last edited by OakMountainRider; 09-01-2024 at 09:25 AM.
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Old 09-01-2024, 09:37 AM
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X
 

Last edited by OakMountainRider; 09-01-2024 at 09:38 AM.
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Old 09-01-2024, 09:45 AM
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Originally Posted by MURPHCC1
[QUOTE So now I am thinking of switching the ION-system off and then go with whatever plugs and wires I like, like IRDIUM plugs and real fat low resistance wires.
SO, how would you go about shutting the ION sensing OFF?[/QUOTE] It can be done if you have PowerVision. But I do not recommend it to anyone. Just speaking for myself here.
 
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Old 09-01-2024, 10:21 AM
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Originally Posted by Jackie Paper
Johannes, only as a suggestion, but I would get an OEM set. Just like Harley's branded plugs, they probably aren't made by Harley but are spect made with lower resistance then what you see in the auto world.

Your Harley has a ION spark detection system that stops pinging from damaging engine.

Google how does ION spark knock detection work

Thanks for your answer. It is a good advice, but I will measure the wires at the dealer before I buy them there again. The only reason for shutting knockcontrol off, would be if it would malfunction together with low resistance after market wires, which I have read they could do. I would never turn knockcontrol off unless I know I was free from knockcounts. Just speaking for myself here - no advice to anyone.
 


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