NGK-CR8EK plugs after 12,000 miles

[HaulinAshe]

just my 1.5 cents on it.
I read in the article about a year ago that different plugs run at a different temps and pass different temp to the engine walls. They also said that when manufacture decides on the plug it matches the proper plug with the temp in mind.

So, how do we know that these plugs run and produce the same temps?

Because this is still a "CR8--" series plug, that means it is an exact heat range replacement. If you switch to another technology plug, like Iridium, then a heat range crossover must be made.

CR8E and CR8EK are exactly the same heat range plugs, just different styles.

 

[cougar8000]

Because this is still a "CR8--" series plug, that means it is an exact heat range replacement. If you switch to another technology plug, like Iridium, then a heat range crossover must be made.CR8E and CR8EK are exactly the same heat range plugs, just different styles.

Cool, I have learned another thing.

 

[Bounce]

Correct me if I'm wrong.

Won't the computer controlled ignition compensate for all but the worst of problems (oil or fuel fouling for example)?

The result is that plugs will "look good" and "read well" even if they aren't at their prime any more. The computer compensates for an optimized burn but at the cost of performance somewhere else (mpg, hp, etc.). In the end, trying to "read plugs" in a modern engine has limited function and can be misleading if used to try and determine if extended service intervals are justified.

 

[S76]

Correct me if I'm wrong.
Won't the computer controlled ignition compensate for all but the worst of problems (oil or fuel fouling for example)?

The result is that plugs will "look good" and "read well" even if they aren't at their prime any more. The computer compensates for an optimized burn but at the cost of performance somewhere else (mpg, hp, etc.). In the end, trying to "read plugs" in a modern engine has limited function and can be misleading if used to try and determine if extended service intervals are justified.

To the best of my knowledge (yeah, we're already on shakey ground) to "read" a plug only gives you an indication of what type of fire you have in the cylinder. Rich or lean. Not counting signs of detonation etc. Light gray to light tan in the center with tan around the outer shell is a pretty good mixture. This tells you how the computer is managing the "Fire." It does not give you a health indiction of the plug or a prediction of it's usefull life. To determine that you need to look at the tip of the round center electrode. If the center electrode tip has sharp 90 degree edges then it is in near to new condition. As the plug wears the edges of the center electrode will round off as metal is dispaced. You may also see wear on the target, or the part you bend to adjust the gap, but not usually. If you do a visual inspection of the center porcelon for cracks, the plug threads for galling, a gap check, an inspection of the exterior porcelon for cracks and all looks good there is no reason the plugs should not continue in service.

Older vehicles used to wear out spark plugs because of the old "point" type breaker systems. These systems did not end the spark cleanly after it fired, causing a drizzle of the spark which caused the errosion and metal displacement of the center electrode. Today's electronic ignition ends the spark quick and clean, minimizing metal transfer. That is why regular plugs in your car today will last 40K miles. I pulled my factory platnum tip plugs out of my car at 90K and they were just like new. Now the FJR plugs aren't platnum but should still last a long time. A lot more than 8K.

And while I am rambling on here I have to say I have doubts as to the effectivnes of the dual target EK plugs. I read test reports on these 30 years ago that said they were no better than a regular plug. Worse in some cases. In 2 cycle engines the second target shields the center electrode from some of the combustion chamber heat causing the plug to foul more often. When that spark gets to the end of the center electrode it is going to make a decision as to which target to jump to. It will decide on which one is closer. You don't get a dual spark or anything like that. The only advantage is when one side of the electrode wears away and the gap gets bigger the spark will start using the other side until it gets bigger too. These plugs are just smoke and mirrors.

$.02

 

[HaulinAshe]

Correct me if I'm wrong.
Won't the computer controlled ignition compensate for all but the worst of problems (oil or fuel fouling for example)?

The result is that plugs will "look good" and "read well" even if they aren't at their prime any more. The computer compensates for an optimized burn but at the cost of performance somewhere else (mpg, hp, etc.). In the end, trying to "read plugs" in a modern engine has limited function and can be misleading if used to try and determine if extended service intervals are justified.

To the best of my knowledge (yeah, we're already on shakey ground) to "read" a plug only gives you an indication of what type of fire you have in the cylinder. Rich or lean. Not counting signs of detonation etc. Light gray to light tan in the center with tan around the outer shell is a pretty good mixture. This tells you how the computer is managing the "Fire." It does not give you a health indiction of the plug or a prediction of it's usefull life. To determine that you need to look at the tip of the round center electrode. If the center electrode tip has sharp 90 degree edges then it is in near to new condition. As the plug wears the edges of the center electrode will round off as metal is dispaced. You may also see wear on the target, or the part you bend to adjust the gap, but not usually. If you do a visual inspection of the center porcelon for cracks, the plug threads for galling, a gap check, an inspection of the exterior porcelon for cracks and all looks good there is no reason the plugs should not continue in service.

Older vehicles used to wear out spark plugs because of the old "point" type breaker systems. These systems did not end the spark cleanly after it fired, causing a drizzle of the spark which caused the errosion and metal displacement of the center electrode. Today's electronic ignition ends the spark quick and clean, minimizing metal transfer. That is why regular plugs in your car today will last 40K miles. I pulled my factory platnum tip plugs out of my car at 90K and they were just like new. Now the FJR plugs aren't platnum but should still last a long time. A lot more than 8K.

And while I am rambling on here I have to say I have doubts as to the effectivnes of the dual target EK plugs. I read test reports on these 30 years ago that said they were no better than a regular plug. Worse in some cases. In 2 cycle engines the second target shields the center electrode from some of the combustion chamber heat causing the plug to foul more often. When that spark gets to the end of the center electrode it is going to make a decision as to which target to jump to. It will decide on which one is closer. You don't get a dual spark or anything like that. The only advantage is when one side of the electrode wears away and the gap gets bigger the spark will start using the other side until it gets bigger too. These plugs are just smoke and mirrors.

$.02

The dual electrode plugs do not provide a split or dual spark. They do offer an increased chance of the plug firing properly under less than ideal conditions. And as you very accurately noted, they will typically fire to the closest electrode.

All the engineering and mental anguish aside, proof is usually in the real world application. I started using these plugs in 4-stroke dirt bikes because in that environment, tip-overs and hot-start fouling conditions are common. So I decided to give them a try in the FJR. My proof is in the feel, starting performance and visual inspection of the plugs after 12,000 miles.

I don't baby my engines, but I do take excellent care of them and do all my own maintenance (have for many years). My experience with these plugs so far is that they outperform the single-electrode CR8E in cold-start and high-acceleration situations. That makes them worth the few extra bucks for me.

The visual inspection (and subsequently posted photos) is intended to share information. You cannot determine the exact condition of my engine or plugs from the photos. But you can assess the general condition of both from the photos. Visual interpretation is a non-exact science. But years and years of reading plugs tells me that things look pretty darn good for 12,000 miles. I have yet to regret spending a few extra bucks and also trying a different-than-stock plug.

NGK has not convinced me that it's worth the extra bucks for Iridium yet. But like most racers, I always entertain possibilities.

So please run out, buy and install four(4) new Iridium plugs, run them 24,000 miles and then post some closeup pictures so that I can have my $.02 also. I'm sure it will SPARK my interest!

 

[jestal]

Older vehicles used to wear out spark plugs because of the old "point" type breaker systems. These systems did not end the spark cleanly after it fired, causing a drizzle of the spark which caused the errosion and metal displacement of the center electrode. Today's electronic ignition ends the spark quick and clean, minimizing metal transfer. That is why regular plugs in your car today will last 40K miles. I pulled my factory platnum tip plugs out of my car at 90K and they were just like new. Now the FJR plugs aren't platnum but should still last a long time. A lot more than 8K.

The REAL reason that plugs never lasted very long in older vehicles was because of leaded fuel. Leaded fuel causes lead fouling of the porcelean on any type of plug making plug changes every 10K pretty much mandatory.

The newer type ignition systems will "handle" fouled or less than optimum plugs better due to increased voltage capability but both the electronic systems and points systems fire the plug when the feed to the coil is interrupted so I think it would be hard to tell between the coil being triggered by points or electronics. Maybe....but not enough to change plug life significantly from what I've seen. .

I think you may be looking at two different changes in the plugs mentioned earlier. If they are indeed copper core plugs AND have dual ground electrodes then those are two separate design changes. I suspect any improvement in performance was due to the copper core of the center electrode rather than the dual ground electrodes.

The real advantage to copper core plugs mentioned is that the porcelean around the center electrode can be longer and yet maintain the same heat range. A longer porcelean always improves fouling resistence whether it be from fuel, soot, oil, etc. It won't make the engine run any better under normal conditions, however. In the case of a flooded cylinder or oil fouled plug in a two stroke the extended porcelean can offer advantages with running and starting. Maintaining the same heat range with an extended tip is is possible because the copper inside the center electrode conducts heat better than normal nickel steel or Inconel. The heat range of the plug is determined by the tip temperature running under load so a copper cored center electrode will conduct more heat and thus run at the same heat range with the porclean lengthened. On a cold starting test a conventional plug might build carbon and fail to start after 40 short start cycles where a copper cored plug with the lengthened tip might go 55 cycles due to the extra length.

I have seen positive, irrefutable evidence of HP loss with dual and +4 ground electrode plugs in several different automotive gasoline engines. The 'extra" ground electrodes tend to suck heat out of the flame kernal initiated at the spark plug gap and slow the burn slightly or impede it in some cases. True that in the real world the difference in fouling resistence or less wear with two (or more) ground electrodes might provide some benefits....maybe....but I doubt it. I think they are a marketing gimmick. Dyno tests would have to be run on any given engine to see positively if they affected the power in that engine. I would not besurprised if dual ground electrodes hurt power and I would be VERY suspicious if they improved anything.

Proof on iridiums? Iridium center electrodes look like brand new in automotive engines at 100K plus. Due to the material properties of iridium the center electrode can be very small diameter allowing a "sharper" edge for spark initiation compared to conventional large diameter center electrodes. Dyno results do show modest power gains with iridium plugs. Not so much for any combustion improvement but from the fact that there is simply less misfire with the iridiums due to their center electrode geometry and long life.

 

[v65]

I think jestal just cost me a few bucks

 

[Geezer]

I think jestal just cost me a few bucks

And saved me a few. I'll stick with the iridiums I already have on the shelf.

 

[warsw]

I think jestal just cost me a few bucks

And saved me a few. I'll stick with the iridiums I already have on the shelf.

What iridium plugs are the right ones for the 06 FJR?

 

[Bounce]

So please run out, buy and install four(4) new Iridium plugs, run them 24,000 miles and then post some closeup pictures so that I can have my $.02 also. I'm sure it will SPARK my interest!

thanks to everyone for the additional info.

here are my oem plugs at 12k

here are the iridiums at 28k (16k on the plugs)

the gunk on the threads is anti-sieze that i used less of during the next plug swap. all electrodes and terminals(?) looks the same and were consistent between all plugs (both times). any visual differences are a trick of the camera angle.

 

[jestal]

I got some questions on the comments I made above and wanted to add:

Understand that the spark is initiated by the "points opening" or the electronics shutting off current to the coil. The voltage from the coil to fire the spark comes from the field in the coil collapsing. The spark ends when the voltage from the coil runs out or drops below the amount necessary to jump the gap....not when the points open or anything like that. Changing coil designs might affect the "end" characteristics of the spark but the points opening does not affect the end characteristics of the spark. The points opening starts the spark, it doesn't end it.

One other advantage on some copper core plug designs is when the plug tip is extended from the original design location. As mentioned, the porcelean can be longer and maintain the same heat range so that feature can be used to extend the tip further into the combustion chamber. That can often make a little more power if it is advantageous for initiating the flame propogation in that particular chamber. If you could get a picture of the FJR stock plug next to those copper core plugs (side-by-side) to visualize the length and projection of the center electrode it might also shed some light on the observations.

Every engine and combustion chamber has some unique characteristics so to be positive one would have to run the FJR on a number of tests to decide which plugs are the "best." Obviously, the good experience so far with the iridiums tends to support my observations of iridiums in controlled dyno and vehicle testing. The copper core plugs might make a positive difference, too. I cannot say for sure that they don't on the FJR....I can only say what I have seen happen with them on other engines.

Realize that the reasons for selecting copper core plugs can be different for different applications and different engines. I personally released copper core plugs for many years in several engines in production due to the added cold fouling resistence of the longer allowable porcelean tip. The projection was the exact same on those plugs and the power and all other characteristics were the same. If someone who lived in Kapuskasing, Ontario and cold started at -40 each morning in the winter and drove short trips were to evaluate the plugs they would definitely report that the copper core plugs were "better" as their engine would run better for them over the long haul.....but.....no one else would notice. Same thing for a dirt bike that gets dropped and liquid fuel runs into the chamber. The copper core plug might provide a fouling advantage that one wouldn't see on an FJR...unless you drop it a lot.

 

[Scab]

an FJR...unless you drop it a lot.

Huh? What? I swear, I don't know what you're talking about.

 

[HaulinAshe]

I'm still trying to see exactly what the Iridium plug number is for the FJR?

It looks like a something-8-something in the pic. I'm also a bit uneasy about that because we did some testing on race bikes where the Iridium required a different heat range number than the copper core plug.

Jestal, please share more.

 

[MKO]

So please run out, buy and install four(4) new Iridium plugs, run them 24,000 miles and then post some closeup pictures so that I can have my $.02 also. I'm sure it will SPARK my interest!

thanks to everyone for the additional info.

here are my oem plugs at 12k

here are the iridiums at 28k (16k on the plugs)

the gunk on the threads is anti-sieze that i used less of during the next plug swap. all electrodes and terminals(?) looks the same and were consistent between all plugs (both times). any visual differences are a trick of the camera angle.

Where can you find a deal on the Iridiums? How much do they cost?

 

[jestal]

I'm still trying to see exactly what the Iridium plug number is for the FJR?
It looks like a something-8-something in the pic. I'm also a bit uneasy about that because we did some testing on race bikes where the Iridium required a different heat range number than the copper core plug.

Jestal, please share more.

Not sure what you are looking for.

When you say you needed a different heat range with the iridium does that mean the iridium plugs needed to be colder or hotter?

The heat range itself should always be equivalent (within a given brand of spark plugs) as long as the heat range number is the same. Depending on the type/design of the spark plug the tip extension or length of porcelean could easily be different even though the heat range was the same. Depending on how that particular plug company changed the design to go to the iridium plug from the copper core plug they might recommend a different heat range TO KEEP THE SAME TIP EXTENSION for example. But the alternate heat range would still be hotter or colder if the number were different. I cannot imagine a plug numbered the same being of a different heat range.

The heat range of the plug just indicates the center electrode tip temperature under heavy load and/or the plug's equivalent resistence to initiating preignition. The tip temperature will be determined by the length of the porcelean (between the tip and where it intersects the shell of the plug), the shell design, the material of the tip, the extension of the tip, etc. It is very possible to have plugs of the same heat range that have totally different tip configurations, tip extensions, etc. You may have been comparing plug design differences caused by achieving the same heat range instead of just the heat range itself.

Typically the heat range of the plug will have absolutely no impact on the power of the engine or how well it runs. As long as the plug is hot enough to clean off the carbon and cold enough to avoid pre-ignition then the plug will operate fine. Differences such as tip extension (the distance the gap extends from the end of the shell), ground electrode style and orientation, porcelean length, etc. will often have an effect on power and the ability to resist misfire regardless of the heat range itself.

As an example: In a two stroke road race bike running castor oil or equivalent a very long porcelean could be desireable for fouling resistence. If an iridium plug were substituted the porcelean would be physically shorter than the equivalent heat range copper core plug. If the iridium caused misfire due to fouling (of the shorter porcelean) then a "hotter" iridium plug might be needed for the added porcelean length, not necessarily for the hotter tip operating temperature. This is just a made up hypothetical example of what could go on, not something that I have actually seen, but, "could happen" I suppose. Similarily, if the tip extension of the copper plug was greater then you might need a "hotter" iridium plug to get the same tip extension if that particular manufacturer added tip extension to make a hotter plug instead of just burying the porcelean deeper inside the shell and keeping the tip extension the same. There are several different design changes that go hand in hand with heat range that can often confuse an otherwise "apples to apples" comparision.

The heat range really is a measurement of the plugs ability to reject heat from the tip. One of the driving forces for this is the brake mean effective pressure of that particular engine. Usually, the heat range number will have some reference to the BMEP of the engine it was designed to operate in. A spark plug engineer can take the specific output of the engine and quickly tell you the ball park heat range of the plug required based on the BMEP data. It wouldn't make sense to have plugs of the same heat range numbered differently or vice versa as the example proposed suggests.

CR8EIX

https://www.ngk.com/results_appOther.asp?ot...1115&mfid=1

 

[HaulinAshe]

Well I'll be a redneck's uncle and brother-in-law. Wait a minute, I am!!!



Last time I checked around here, and that was not too long ago, the discount parts stores were charging $14-$16 each for the Iridium plugs. Thanks for the link Jestal.

BTW, our tests have sometimes indicated the need for one grade hotter plug in two-strokes, and one number colder plug in 4-strokes. But it's been limited testing, mainly because the cost of the Iridiums has been so damn high.

 

[Bounce]

CR8EIX is what I used and Jestal's link is about what I remember paying for them through the local NAPA place. The first time they were in stock. The 2nd time they got them in the next day.

 

[FJRMGM]

I got my iridiums at the local Auto Zone - they had to order but were there the next day for about $6.50 each.

I now have about 28,000 miles on them and will pull them out and take pictures this weekend when I do the throttle body synch while I have the tank up.

 

[Feejer/Weejer man]

Just after some starting using the Iridiums a few years ago I bought two sets. All this info has been posted for a couple of years now with all the technical data. Any plug will have diminishing returns after extended mileage including the Iridiums, but because of the composition of these plugs will last longer but still should be replaced at recommended intervals or close to it anyway. Some go to 12,000+ before a change.

 

[warsw]

CR8EIX
https://www.ngk.com/results_appOther.asp?ot...1115&mfid=1

jestal, have you found ngk.com to be a good place to order plugs or at least as good as anywhere else?