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Discussion Starter · #1 ·
I have a 1984 ZN1100 that is in need of two new ignition coils. I am looking at Dyna coils and have done a ton of reading which leaves me wondering which coil and which spark plug wires are best for my application.

Looking at the coils first:
Dyna recommends their 3 ohm DC1-1 for my bike, but my understanding is that these 3 ohm coils are actually designed for their ignition system that I will NOT be using. I am sticking with the stock igniter. Most of what I have read indicates that the new coils need to match the resistance of the primary circuit of the OEM coils since that is what the igniter expects to see. Kawi says their OEM coils should have a primary resistance of 1.8-2.8 ohms. The middle of that range is 2.3 ohms. So using 2.2 ohm coils would be a much better match unless I am missing something here.

I have also read that if you never plan to upgrade to the Dyna electronic ignition, then the Dyna 2.2 ohm coils work better with the OEM igniter from Kawasaki. Has anyone done this and how did it work out for you? Would love to hear of anyone who has fitted the Dyna 2.2 ohm coils to any of the Kawi big fours.

Looking at spark plug wires:
I went down a deep rabbit hole on this one. There is so much conflicting info out there. I will summarize what I think is accurate. It all comes down to total resistance in the circuit from coils to spark plug.

1) In Canada and Europe the spec was to always use resistor spark plugs ie BR8ES. ("R" denotes Resistor)
2) In USA the spec was to use non-resistor plugs like B8ES.
3) In USA the resistance was provided by either suppression built into the spark plug wires or by using resistor spark plug caps.
4) Many sites advise to ONLY use resistance in one location so if you use suppression wires, don't use resistor spark plugs or resistor spark plug caps. This makes sense but in that case, why did my bike come with resistor spark plug caps and used the Canada specification resistor spark plugs? Did a previous owner mistakenly swap out non resistor spark plug caps for resistor caps? Or did we get double resistance for some reason?
5) And finally, some sites advise to use suppression wires if you have electronic ignition especially if your bike has an electronic advance, which my bike does. They claim the electrical interference from non-suppression wires can mess with the igniter.

If anyone with a bike with OEM electronic advance igniter has swapped out their plug wires, I would love to hear what you did and how it worked out.
 

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I can't really help but my ZN700 has copper wires, non-resistor plugs, and 5k ohm plug caps. My bike only had 1k miles on it when I bought it so I'm sure it's OE except for the plugs of course that I changed using the manual for guidance. Send a message to Hoyt Clagwell to see if he will respond. As I remember he installed dyna coils on his ZN1100. Hoyt has or had his bike up for sale and bought a BMW Z4 I think to play with.
 

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Discussion Starter · #3 ·
Actually it does help. It confirms my suspicions of how US bikes were fitted and it would confirm that Kawi designed their igniters to not need suppression wires; if you are sure yours were copper. My wires look original and with caps removed they measure almost zero ohms of resistance. They might not be copper, but they are not suppression wires. This again would tend to confirm that I don't need suppression wires.

So while you have only 5k of resistance, I end up with 10k. That's not fair. ;)

Meanwhile I continued my deep dive into the resistance issues. I found that the relatively low resistance (in comparison to sparking voltages of ~20,000 volts) has some learned folks saying the resistance is too small to worry about. Hope they are right.

If you want to find out just how complicated this topic is, go here and be prepared for a good half hour of reading stuff that you may or may not understand. I did find it super interesting but then again, I am a bit of a nerd for stuff like that.

 

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My 89 Yamaha Venture Royale has copper wires and 9k ohm caps. it only has 6k miles on it so I'm sure they are the original caps and that agrees with info on the venture forum. I think they are speced at 10k ohms. But, my Venture does not have the seals on the caps and water gets into the cap and corrodes the copper wires turning them green. A common repair is to cut off a half inch or so of copper wire to fix the high wire resistance. The NGK replacement caps are all 5k ohms resistance I think. Several venture members replaced their coils, wires, and caps with cops. One owner said he used Suzuki Hayabusa cops bought used off ebay. Some worry about the ignition box burning out if the resistance gets too low.
 

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Discussion Starter · #5 ·
Thanks RoadRunner322,

As an update from further research. It appears that it is illegal to sell non-resistor spark plugs in Canada.
The resistor plugs have 5k Ohms of resistance as you mentioned.
NGK non-resistor plug caps are as scarce as hen's teeth in Canada.
If you want to run a radio or bluetooth on your bike, you need suppression plug wires also, or you will hear lots of static.

Have you thought about replacing your caps on your Venture to prevent future corrosion?
NGK spec with a "P" at the end stands for waterproof. As an example, LB05FP.

Here is a link to the NGK plug caps with codes explained.

 

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Thanks for the info on waterproof NGK plug caps. My ZN700 has something like an O-ring in the end around the wire to keep moisture out. The Venture needs waterproof caps because it is a very common issue on these old Ventures for the copper core of the wires to corrode at the caps.
 

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Discussion Starter · #7 ·
I just picked up new NGK resistor caps from my local auto parts store.
I got two 90 degree boots (LB05FP) and two 102 degree boots (XB05FP).
They come with waterproof connectors for both ends of the cap and are fairly inexpensive at around $5 CDN per cap.
 

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The green Dyna 3.0 ohm coils are a fairly common choice w the stock electronic ignition system, but according to loudhvx the grey 2.2 ohm are supposed to be a better match. loudhvx is kind of an expert on electronics & vintage electrics.

I went with the green 3.0 ohm coils on my 81 KZ650-CSR w stock electronic ignition, in case I had to switch to the Dyna S. It's been more than 5 years w no problems. I also installed a Dyna 7mm copper core spark plug wire set & I'm using ND W22ES-U spark plugs (equivalent to NGK B7ES).

I'm not versed in resistor spark plugs or suppression plug wires. Some say you should use one or the other, but I don't know what's best. I didn't go with either.
 

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Discussion Starter · #9 ·
Thanks Martin,

Good info.
Based on info rec'd here and from various other sources, I have placed my order for the 2.2 ohm Dyna coils DC4-1.
I figure if my old bucket of bolts ever needs a new electronic ignition, it is going to be parted out. I just cannot afford to throw more money at it. So from here to the end of its days it will live with these coils.
 
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