[ghostt]

I did modification to my Ninja 250 first, but will be doing it to the EX.

Here's my write-up I did for Ninjette.org


I've decided to do the coil over plug modification on SERENITY, so first step was to purchase the coils.

After looking on eBay I found a set for 00-02 Kawasaki ZX6R ZX6 05-08 ZZR600 Engine Motor Ignition Coil Packs w/ Harness, for a total cost of $30.00. Must have the harness which is needed to adapt the Ninjette wiring to the coils. It's important to get the harness, because the coil connectors are different.

Next step was to unwrap the coil harness, so I could cut the OEM connectors from the harness.

Cut at the OEM splice points, which there are two.

OEM connectors ready for modification.

Wiring is easy just connect the red to the red wires, and the other wires to each other.

SIDENOTE: temporarily I've put male blade ends on the coil over connectors, so to just plug them into the existing wiring on the Ninjette. I did this while I'm testing these out, if something goes wrong I can easily plug the old ones up. Once I'm confident in them I will splice and solder them permanently, and removing the OEM coils

After that it's just as simple as installing the coil overs like you would the regular plug caps.

Removed the OEM coils

Final verdict: no real noticeable difference between the OEM Vs ZX coils. The advantages are eliminating the plug wires, and the spark plug caps, which need to cleaned, less to go wrong hopefully. After testing, I decided to remove the OEM coils, and brackets, which by the way they were spot welded on.

 

[urbane]

What is the benefit of this?

 

[ghostt]

Re:

Less to go wrong, less weight and maybe a little bit better spark. As I have way to actually test it, I'm just going on the obvious assumptions, time will tell.

I'm also assuming the same differences that Kawasaki thought about, when going to this setup.

 

[InvisiBill]

Real Soon Now™ I'll get around to installing the CoPs I bought a year and a half ago... Currently the plan is to mate them up to the OEM connectors for a completely PnP, reversible install.


Here are some quotes from a guy over at Ninjette about the upgrade:

the gains from this type of coil comes from the lowered resistance going from the collapsing field into the output coil and into the plug... if you look up joules law you'll see as you lower that resistance, you get higher inductance joules going through the plug for the same amount of charge current (from cdi) which means the spark is hotter and will last slightly longer.

for a stock setup, the difference shouldn't be obvious as the stock coils are "good enough". but when you get into higher performance stuff like changing timing and compression, you can get larger changes.

i think it makes very little difference in either unless you are running very aggressive timing. also, my understanding of the way the system works when i wrote that was slightly naive. i believe the most important aspect is how quickly the field is able to collapse into meaningful heat, and stay in a range that the plug is designed for. and how reliable the size of the field is so you don't over-charge the field and burn electrodes.

Basically, as long as everything stock is working right, there's not really any performance to be gained from this. If you're pushing things and your spark is borderline, this might be enough to bring it back up to adequate. The biggest gain is probably the simplification of the ignition wiring - getting rid of the big coils and problematic plug wires.

One thing to note is that the 250 has small plug wells like the bikes these CoPs were originally used on. The 500 has a much more open plug area, so you might need to add something to help support it.

A couple related threads...
http://www.ex-500.com/index.php/topic,23810.msg573880.html#msg573880
http://www.ex-500.com/index.php/topic,40290.0.html

 

[ghostt]

Re:

As far as adapting the CoPs harness to the Ninjette was easy enough, I just used male spade connectors, to plug into the Ninjette OEM which has female spade connectors.

I ran it like this while I tested them out, but have since done away with the connectors, and soldered them.

One good thing I did get 4 coils, so now I can either have spares or install them on the EX.

 

[InvisiBill]

Re:

As far as adapting the CoPs harness to the Ninjette was easy enough, I just used male spade connectors, to plug into the Ninjette OEM which has female spade connectors.

I ran it like this while I tested them out, but have since done away with the connectors, and soldered them.

Yeah, I was being OCD and trying to find something ready-made that was comparable to speaker terminals. Ideally, I wanted to have the new CoP wires go directly to some sort of terminal block that had color-coded male spades on it, so the OEM wires could just be plugged right in, completely idiot-proof. I've got some simple male disconnects to put on the wires for now.

 

[InvisiBill]

Guess what I did today?

I basically did the same thing as Ghostt described above. Mine were listed as coming from an '04 ZX-6R (636), and the harness was a bit different. I only had one of the splices in mine, resulting in two of the plugs having significantly shorter red wires than the other two. If you look at his pic of the harness, you can see that the middle two have shorter wires than the outside two. I thought the reduced length might be a problem, so I started with one of the longer ones, and just happened to pick the left side of the bike to start on.

The left OEM coil wires are in a bundle with the wires for the fan switch. Once you get the coil out of the way, the wires are plenty long to reach the new CoP though. I found some insulated male .25" disconnects, and they slide perfectly over the insulted female disconnects that plug into the OEM coil.

I was hoping to make two CoP sets out of what I had, so I didn't want to use both of the long-wire plugs if I didn't have to. However, the short wires weren't long enough to reach over to where the OEM coils plugged in. Luckily, the right OEM coil wires aren't bundled with anything else, and are routed pretty excessively toward the outside of the bike. I was able to simply pull the OEM coil wires back toward the neck area, then feed them more directly toward the spark plug area. With the position of the OEM coil wires adjusted like this, the short-wire CoP plug was the perfect length. Once more with slapping on the male disconnects for a PnP connection to the harness, and my conversion was complete.

After starting up with the new CoPs installed, it might be a tad bit smoother. However, I also started it up several times while I was working on things with the tank off. The petcock vacuum hose was left open and it only had whatever gas was left in the carb bowls (I ran it for a second with the petcock off before disassembly too, hoping to empty out the fuel line to avoid spills), so it was running less than perfectly for several starts just before my finished CoP test. That absolutely could have skewed my perception. Like the stuff mentioned in my previous post, I'm not really expecting any major improvements from this, but it cleans things up a bit (combined with the PAIR removal, the top of my engine is greatly simplified now) and removes the spark plug wires that are known to develop issues over time.

 

[I am the stig]

Nice Ghostt and Bill! Bill, how is the stability of the cop in the well? This sounds like a mod for the track bike.

 

[InvisiBill]

Nice Ghostt and Bill! Bill, how is the stability of the cop in the well? This sounds like a mod for the track bike.

Meh. There's not a whole lot keeping it in place.

The actual coil is just sort of balanced on top of the plug, held on with some spring tension to maintain electrical contact.

The boot at the bottom does help hold it on, but it's fairly soft rubber, as opposed to the rather rigid stock boots.

I haven't done anything to help support it, but I also haven't even ridden it yet. One of the threads I linked above mentions using the leftover PVC pipe from his new fork springs to help support the coils, but those were from a 650 and slightly different. I'd love for someone to make some PAIR blockoff plates with perfectly-spaced loops in them, and the coils could just slide right through (ideally matching the top of the ZX-6R's plug wells exactly, so the CoPs would fit here just like they do there). Slightly less perfect, I might go for some sort of separate bracket on top of the PAIR plates. For now, I'll probably just find a chunk of PVC that fits, as an easy way to add some reinforcement. Since the plug wells are so open, you probably want to do something to keep them in place.

Also, this pic illustrates just how short the wires were on half of them. I actually pulled apart the crimped splice rather than cutting the wire at the splice, so that's 100% of the length of the red wire in the OEM harness (with the black wire cut to match). In the previous pic of the right side, the junction must be just out of sight, right behind the frame.

 

[I am the stig]

Humm, maybe a little water pipe insulating foam..........

 

[londart]

I'd love for someone to make some PAIR blockoff plates with perfectly-spaced loops in them, and the coils could just slide right through (ideally matching the top of the ZX-6R's plug wells exactly, so the CoPs would fit here just like they do there). Slightly less perfect, I might go for some sort of separate bracket on top of the PAIR plates.

Wouldn't that defeat one of the main reasons for pair removal, easing access to the plugs during tune-up?

 

[ghostt]

I've put about 500 miles on my setup, and so far, so good. No ill effects from just letting sit on top of the plugs. They fit tightly on the plugs, and no signs of loosening.

Maybe I could modify the OEM rubber tops from the OEM caps, this might add added some support. I suppose the same could be done for the EX.

Perhaps a piece of rubber hose to slip over the CoPs, to thicken it's diameter a bit, and snug inside the spark plug well, and add stability.

The ninja 250 uses a slightly different top than the EX, it's oblong in shape.

But as I stated the CoPs are still solid, and working perfectly.

 

[InvisiBill]

Wouldn't that defeat one of the main reasons for pair removal, easing access to the plugs during tune-up?

Maybe a little. The rubber mount at the top of the CoP is 28.5mm in diameter while my Motion Pro spark plug socket is under 24mm. The bracket would be in the area where you're working, but you should be able to stick your socket/extension straight down through it to remove the plug. I'm willing to settle for a slight reduction in convenience there if it means getting a perfect duplicate of the OEM ZX retention system. I'm sure this will be one of my Round Tuit projects, and I'll just stick some PVC or something on there for now.

 

[I am the stig]

Story of my life......

 

[InvisiBill]

I took a nice 60 mile ride tonight. No spark issues yet, and it might have felt a tad bit smoother. Again, if there is any change, it's small enough for me to doubt it's even there. This won't give you an extra 10hp unless there's something massively wrong with your ignition to begin with. It does do a decent job of cleaning up the top of the engine and avoiding the issues related to plug wires.

 

[fog]

I have stated in the past that the spark generating system on the EX was so puny it could barely fire a .025 gap. this seriously hampered the production of power at High Revs.'
I think you plug cap /spark coil mod is a good Idea, but to really gain the benefits of a stronger spark ,you have to make one.
DId you enlarge the plug gap at all. if not ,why not? I would start with .03 or maybe .035 and see
The bigger the gap the bigger the spark.
OR find out the recommended gap of the engine you acquired the coils from.

FOG

 

[Saabnut]

That is an idea worth pursuing FOG. I purchased a set of coils from an '05 Kawi 636, googled the plug information and came back with CR9E as the plug type with factory gap specs .028-.031. That puts the heat range as the same for the EX with and the gap slightly greater than stock, so I'll set the gap at .030 and go from there.

 

[ghostt]

Re:

I have not open up the gap past the OEM recommend. Correct gap is .6 - .7 mm for the Ninja 250.

I will give that a try next, Thxs.

 

[fog]

OEM for what? you want the correct setting from the ZX6 the whole point of the switch is to get a better spark try and get one.

FOG

 

[ghostt]

Re:

07-08 Zx6 Spark Plug Gap: 0.7 ∼ 0.8 mm (0.028 ∼ 0.031 in.)