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NGK PLUGS DEMYSTIFIED?


markgoodrich

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I'm starting a new thread on this subject, which has many older threads, to hopefully illuminate all of us on the mysteries of the super-expensive BMW-dealer NGK plugs. I called the NGK tech line and got a very concise, exellent explanation of the

various designations.

 

BMW calls for NGK DCPR8EKC plugs, available only through BMW dealers in the U. S. It's a dual ground plug (that's what the "K" designation means) with a nickel tip (the "C" denotes nickel).

 

The exact plug, only better, is widely available at less cost as the NGK DCPR8EKP, with the "P" denoting platinum tip, thus longer life.

 

The tech guy recommended against their iridium plug or their single-ground plug, as he said not only do the plugs not extend as far into the combustion chamber, but they don't provide as complete combustion as the duals. [i realize many use the singles, I'm simply reporting here].

 

Most auto parts store sites require input of your car info...use a BMW M3 and you'll get the right plug. Or, order from Amazon, get free shipping, no sales tax, works out to about the same. They're about $12 each, everywhere I looked.

 

I'm aware there are UK sites which sell the OEM plug at low prices; here's one someone on the MOA forum bought from.

 

 

 

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I'm starting a new thread on this subject, which has many older threads, to hopefully illuminate all of us on the mysteries of the super-expensive BMW-dealer NGK plugs.

?????

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The exact plug, only better, is widely available at less cost as the NGK DCPR8EKP, with the "P" denoting platinum tip, thus longer life.

 

If it's better, then I wonder why doesn't BMW offer them at least as an option? One could argue that BMW wants us to use their "recommended" plug because they make more money since they must be changed more frequently and only BMW dealers sell them. Or maybe BMW does not recommend them for a some other very valid reason. Finally, your post raises the question as to how much longer the platinum plugs will last (the ones in my car are good for 105K miles).

 

Sounds like you had an interesting discussion with the NGK rep. Thanks for reporting your findings.

 

Jay

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The exact plug, only better, is widely available at less cost as the NGK DCPR8EKP, with the "P" denoting platinum tip, thus longer life.

 

If it's better, then I wonder why doesn't BMW offer them at least as an option? One could argue that BMW wants us to use their "recommended" plug because they make more money since they must be changed more frequently and only BMW dealers sell them. Or maybe BMW does not recommend them for a some other very valid reason. Finally, your post raises the question as to how much longer the platinum plugs will last (the ones in my car are good for 105K miles).

 

Sounds like you had an interesting discussion with the NGK rep. Thanks for reporting your findings.

 

Jay

 

Jay, I should have put the word in quotes: "better" as I was quoting the NGK guy. Better in the sense that the platinum plug lasts longer.

 

If we assume (and I think we can) that the two plugs are identical but for the nickel and platinum tips, then does it follow that BMW specs the nickel because it's proprietary? I dunno. You can buy them on ebay for a few bucks (the KCs) if you sniff around a bit (or read this forum).

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I'm starting a new thread on this subject, which has many older threads, to hopefully illuminate all of us on the mysteries of the super-expensive BMW-dealer NGK plugs.

?????

 

Sorry, Paul, I accidentally posted the first sentence before finishing up, and you read it and sensibly said ???????

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A couple older threads reported great success using the Denso version of the NGK iridium plug. So I find this a bit odd. I'm sitting on four NGK DCP8REIX plugs awaiting 24K service.

 

Are the OEM plugs dual electrode?

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A couple older threads reported great success using the Denso version of the NGK iridium plug. So I find this a bit odd. I'm sitting on four NGK DCP8REIX plugs awaiting 24K service.

 

Are the OEM plugs dual electrode?

 

Yes, the OEMs are dual ground. I've also read of the success of single ground plugs, Denso, NGK, including the IX plugs you have. I was simply reporting what the NGK tech line guy told me. He said the bike'll run with the iridiums, but (remember, I'm reporting what HE said) that you'll get less complete combustion, possibly poorer throttle response, less power, lower mileage, etc. Given the anecdotal success of using the singles, I rather doubt the differences will be noticeable in normal use...plus, you save about five bucks over the price of the platinum doubles from Amazon :thumbsup:

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I'm starting a new thread on this subject, which has many older threads, to hopefully illuminate all of us on the mysteries of the super-expensive BMW-dealer NGK plugs. I called the NGK tech line and got a very concise, exellent explanation of the

various designations.

 

BMW calls for NGK DCPR8EKC plugs, available only through BMW dealers in the U. S. It's a dual ground plug (that's what the "K" designation means) with a nickel tip (the "C" denotes nickel).

 

The exact plug, only better, is widely available at less cost as the NGK DCPR8EKP, with the "P" denoting platinum tip, thus longer life.

 

The tech guy recommended against their iridium plug or their single-ground plug, as he said not only do the plugs not extend as far into the combustion chamber, but they don't provide as complete combustion as the duals. [i realize many use the singles, I'm simply reporting here].

 

Most auto parts store sites require input of your car info...use a BMW M3 and you'll get the right plug. Or, order from Amazon, get free shipping, no sales tax, works out to about the same. They're about $12 each, everywhere I looked.

 

I'm aware there are UK sites which sell the OEM plug at low prices; here's one someone on the MOA forum bought from.

 

 

 

Yep --- I am the guy that posted on the MOA forum and paid that great price from UK as posted on Ebay. The plugs are fine and the bike runs perfectly.. They are the correct plugs.

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I'm not sure about "super expensive". From what I've found DCPR8EKP are being sold between about $12 to $15 online. Max BMW sells the stock DCPR8EKC for $16. If you don't mind waiting for forever and a day to get them, you can get them at Chicago BMW for $12.80.

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I'm not sure about "super expensive". From what I've found DCPR8EKP are being sold between about $12 to $15 online. Max BMW sells the stock DCPR8EKC for $16. If you don't mind waiting for forever and a day to get them, you can get them at Chicago BMW for $12.80.

 

Agreed, Scott, that the price per is not significantly different. However, the tech guy at NGK clearly stated that the KP plugs will last "much longer." While "much longer" wasn't defined more precisely, my own (anecdote warning) experience with platinum plugs in autos is that they last "forever." Autozone, by the way, guarantees the KP version for 3 years....

 

Please understand, all I'm trying to do with this thread is offer information regarding alternatives to the OEM-spec plug direct from the plug's mouth. I'm no expert, not pretending to be, and jeez, the last thing I want to do is create an oil-type thread.

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I'm not sure about "super expensive". From what I've found DCPR8EKP are being sold between about $12 to $15 online. Max BMW sells the stock DCPR8EKC for $16. If you don't mind waiting for forever and a day to get them, you can get them at Chicago BMW for $12.80.

 

Agreed, Scott, that the price per is not significantly different. However, the tech guy at NGK clearly stated that the KP plugs will last "much longer." While "much longer" wasn't defined more precisely, my own (anecdote warning) experience with platinum plugs in autos is that they last "forever." Autozone, by the way, guarantees the KP version for 3 years....

 

Please understand, all I'm trying to do with this thread is offer information regarding alternatives to the OEM-spec plug direct from the plug's mouth. I'm no expert, not pretending to be, and jeez, the last thing I want to do is create an oil-type thread.

 

Understood here and thank you.

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How much longer do you need them to last??

My bike is still running the original plugs, 3 years and 100,000km and counting! :thumbsup:

Sure BMW wants you to change them every 40,000km but why? Everytime I have pulled them out they look like new! So back in they go!

Seems like there are other more important things to worry about! My RT has just sprung it's 3rd final drive seal leak! So far I have had problems with several antenna rings, two radios, two steering bearings, warped front rotors, almost all engine seals have been replaced including the clutch due to oil contamination!

 

Not once have I had a problem with the spark plugs!

I figure if I change them, then they are sure to fail soon after! :grin:

 

 

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I just searched Amazon.com for the DCPR8EKP, and to my surprise they do sell them ($12.10 ea. incl. shipping, no tax).

 

I get most of my consumables from Amazon...oil, oil filters, etc. Wish they sold tires. I even bought a large air compressor from them. Free shipping and watching for deals makes it worthwhile. Never mind the couple of books I always seem to suddenly need when I go to the site, they don't count.

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How much longer do you need them to last??

...

Not once have I had a problem with the spark plugs!

I figure if I change them, then they are sure to fail soon after! :grin:

 

 

Mine looked great at 24k miles but when I measured the gaps, every one of them was far beyond the .1mm max limit - and not just a little.

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I just searched Amazon.com for the DCPR8EKP, and to my surprise they do sell them ($12.10 ea. incl. shipping, no tax).

 

While you're at it, you can get the Purolator PL10241 oil filter two-pack for $5.48 after rebate.

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Mine looked great at 24k miles but when I measured the gaps, every one of them was far beyond the .1mm max limit - and not just a little.

Do you mean 1mm instead of .1mm?

 

I don't know what the spec for the R1200 is but doubt any IC engine has a spark plug gap of .1mm, which is 0.004". Most vehicles are in the 0.025"-0.060" range.

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I have been using them for 15K miles/Jan. 2006 with no problems whatsoever.

 

Notice any difference in mileage and performance, one way or the other?

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Do you mean 1mm instead of .1mm?

 

I don't know what the spec for the R1200 is but doubt any IC engine has a spark plug gap of .1mm, which is 0.004". Most vehicles are in the 0.025"-0.060" range.

 

Sorry, you are correct, the plug gaps should be .8mm to 1mm max. I found most of mine measured more than 1.5mm at 24k miles.

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aggieengineer

The question that pops into my mind after reading the NGK rep's response is: why would a dual ground plug offer better combustion? Is he under the impression that there will be two independent sparks on each plug as it fires?

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The question that pops into my mind after reading the NGK rep's response is: why would a dual ground plug offer better combustion? Is he under the impression that there will be two independent sparks on each plug as it fires?

 

I may have misquoted him; I spoke to the guy, then wrote the note I posted from memory.

 

Here's a link to something else I found, which may or may not be accurate or useful, regarding dual electrode plugs:

 

http://www.factorypro.com/tech/spark_plug.html

 

I'd be interested in your theories on spark plugs, single, dual, etc.

 

 

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BMW motorcycle applications notwithstanding, my experience with dual electrode plugs in automobiles has been mixed. They work great for a couple thousand miles, but when they start to wear or foul, typically one electrode takes over and the other ceases to spark, requiring cleaning and regapping. Obviously, they seem to work well in these bikes and I'm sure the quality of the plugs has a lot to do with it as well.

 

I'm running Iridiums in my gsxr, and in all my other vehicles, and I run "fine wire" plugs (aircraft equivalent of Iridium plugs) in piston aircraft. I think it's fair to say that across the board, performance and/or economy has improved over standard plugs, if only slightly. The gsxr idles and runs noticeably smoother, and aircraft engines start easier in cold weather, and will run smoothly on leaner fuel mixtures.

 

I think I'll go ahead with my plan to put the Iridum plugs in the RT, unless I hear a flood of a lot of negative comments before I hit 24K.

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Did the 24k service today, including the required spilling of the trans oil on the floor after the burning of the fingers on the cat converter, but you're interested in spark plugs, which are as big a PITA to get at as everything else on the RT.

 

The new NGK platinum plug compared to the original Bosch, with 24k miles on it. I expect to double my gas mileage and top speed should increase to 184 mph. Click the pic.

 

th_IMG_1940.jpg

 

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Unhofliche_Gesundheit

re; I'd be interested in your theories

 

hi mark -(or is it Nigel Incubator-Jones ? his best friend is a tree, and in his spare time he's a stockbroker) did you say theory?

in homage to your avatar:

 

 

Miss Elk:

My theory by A. Elk. Brackets Miss, brackets.

This theory goes as follows and begins now.

All brontosauruses are thin at one end, much thicker in the middle and then thin again at the far end. That is my theory, it is mine, and belongs to me and I own it, and what it is too. :grin:

 

( hope this is not too esoteric - but is friday night after all so a little indulgence is to be tolerated... :/ )

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I very much appreciate posts like this Mark because it gives us alternatives. In fact based on what has been said about the KP plugs I'm going to order some up and put them in my RT at the 72k inspection.

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re; I'd be interested in your theories

 

hi mark -(or is it Nigel Incubator-Jones ? his best friend is a tree, and in his spare time he's a stockbroker) did you say theory?

in homage to your avatar:

 

 

Miss Elk:

My theory by A. Elk. Brackets Miss, brackets.

This theory goes as follows and begins now.

All brontosauruses are thin at one end, much thicker in the middle and then thin again at the far end. That is my theory, it is mine, and belongs to me and I own it, and what it is too. :grin:

 

( hope this is not too esoteric - but is friday night after all so a little indulgence is to be tolerated... :/ )

 

This from a person whose name is translatable as "I hawked a booger into your soup, so sorry?" And dresses his dog? Dresses. His. Dog.

 

I do admit to being a bit of a twit, thus the avatar. But just a bit. The rest of me is quite suave. Debonair, even.

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One counter thought about the single ground electrode of the Iridium spark plugs. One factor in igniting the fuel mixture is flow of that mixture at the spark. Wouldn't a dual ground electrode impeade that flow more than a more wide open single ground electrode? My bike is running very well with the NGK DCPR8EIX's in it.

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I just found the NGK DCPR8EKP for $6.82 :grin: I ordered eight of them.

 

Shut UP!

 

Given the potential for misunderstandings using just the written word in forums like this, among people who don't know each other, I should clarify my comment above. The term "Shut UP!" was used in the vernacular sense of "No Way!" as in one woman saying to another, "Shut UP, Girlfriend!"

 

Poor Scott, he may or may not have found a very low price for the KP plugs, but the poor guy thinks he needs eight of them. :eek:

 

 

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Unhofliche_Gesundheit

ScottT magnum RT R1200T from Texas.

uncanny :eek:

 

more useless musings from the desk of Unhofliche Gesundheit ( i.e Rude Health - as in my motah is in rude health innit? - what can i say all the good user names were taken... :)

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The plugs that are $6.82 are the Bosch YR6LDE, whereas the correct Bosch plug is the YR5LDE (slightly cooler). So, unless I misunderstand, RM Euro's plugs aren't quite what we want.

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You are right! I completely missed that the fact that they are Bosch plugs and not NGKs. Arrrgh! Thanks for pointing that out. And they are the wrong heat range to boot. I have just cancelled the order. Hopefully the cancel goes through before they ship.

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You are right! I completely missed that the fact that they are Bosch plugs and not NGKs. Arrrgh! Thanks for pointing that out. And they are the wrong heat range to boot. I have just cancelled the order. Hopefully the cancel goes through before they ship.

 

Maybe it isn't a significant difference? On the Bosch site, 5-6 is the medium range between cold and hot plugs. Both plugs use a nickel-yttrium (the heck is that?) electrode.

 

Here's what Bosch says about heat ranges, followed by a link to reading their codes:

 

The spark plugs’ heat range is an index of its capacity to dissipate thermal energy. The different characteristics of automotive engines regarding operating load, compression, engine speed, cooling, and fuel make it impossible to run all engines with a standard spark plug. The same spark plug may get very hot in one engine type, but may reach only a relatively low temperature in another. In the first case, the air-fuel mixture would ignite on the glowing parts of the spark plug projecting into the combustion chamber (pre-ignition) and, in the second case, the insulator tip would soon become so badly fouled by combustion deposits that misfiring would occur. To ensure that the plug runs between the desired temperatures, plugs with different heat capacities were developed. The so called “heat range”, which is assigned to each spark plug, is used to characterize these heat dissipation capacities. A plug with a low heat range number (e.g., 2-4) indicates a cold plug that quickly dissipates heat to the engine block and cooling system, while a high code (e.g., 7-10) indicates a hot plug that retains heat. By properly selecting the heat range of the plug, it ensures that the plug will operate between the plug’s designed operating range of 500-900 degrees Celsius. In this range, the spark plug will be self-cleaning, yet will not be hot enough to pre-ignite the air/fuel mixture.

 

http://www.boschautoparts.com/NR/rdonlyres/C77B3446-232B-4AEC-AFA9-AD05F2A0A2AD/0/DesignationCodes.pdf

 

It appears, by the way, that the Bosch plug we "need" is not available on their site. It's an OEM designation, I think. Recall that the NGK plug is also specified for the BMW M3. The "6" is what Bosch specifies for that car.

 

REMEMBER: I'm not an expert, I'm just googling.

 

All this discussion raises two questions:

 

1. Why do we have two plugs per cylinder, anyway?

 

2. Why does BMW specify nickel-electrode plugs in their motors (including the M3) instead of platinum?

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1. Large cylinders with big valves leave some of the mixture unburnt with only one plug - the reason BMW went twin-spark was to meet new Euro emissions regs not to get rid of surge, that was just a side effect.

 

2. Nickel plugs are cheaper so they save money (cost base) at the factory - if they fit them there, they spec them for us. (BTW the stock plugs are cheap and available in Europe)

 

Andy

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Kerry in Mpls

Great discussion, here's my tiny contribution.

 

Both plugs use a nickel-yttrium (the heck is that?) electrode.

From

http://en.wikipedia.org/wiki/Yttrium

 

"The addition of yttrium to alloys generally improves workability, adds resistance to high-temperature recrystallization and significantly enhances resistance to high-temperature oxidation."

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  • 3 weeks later...
I'm starting a new thread on this subject, which has many older threads, to hopefully illuminate all of us on the mysteries of the super-expensive BMW-dealer NGK plugs. I called the NGK tech line and got a very concise, exellent explanation of the

various designations.

 

BMW calls for NGK DCPR8EKC plugs, available only through BMW dealers in the U. S. It's a dual ground plug (that's what the "K" designation means) with a nickel tip (the "C" denotes nickel).

 

The exact plug, only better, is widely available at less cost as the NGK DCPR8EKP, with the "P" denoting platinum tip, thus longer life.

 

The tech guy recommended against their iridium plug or their single-ground plug, as he said not only do the plugs not extend as far into the combustion chamber, but they don't provide as complete combustion as the duals. [i realize many use the singles, I'm simply reporting here].

 

Most auto parts store sites require input of your car info...use a BMW M3 and you'll get the right plug. Or, order from Amazon, get free shipping, no sales tax, works out to about the same. They're about $12 each, everywhere I looked.

 

I'm aware there are UK sites which sell the OEM plug at low prices; here's one someone on the MOA forum bought from.

 

 

 

I just replaced the plugs in my RT with NGK iridiums, had I known about the DCPR8EKP before buying the irisiums, I would have probably gone with them instead. Comparing the two plugs, I can see what the tech guy was talking about. Both plugs are the same length but the center electrode on the DCPR8EKC extends further and because its ground electrodes are on the side rather than below the center electrode, the spark not only is deeper in the combustion chamber, it's also less obstructed. However, based on the experience of others using tje iridium and my own short test ride, it doesn't seem to have a significant efect on the RT. During my test ride, the RT actually seemed to run a bit smoother but that could be my inmagination or the result of new versus old plugs.

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I think this topic is being over analyzed... I would stick with stock plugs unless you want to do the NGK platnums. BMW specs these plugs for a reason..

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I think this topic is being over analyzed... I would stick with stock plugs unless you want to do the NGK platnums. BMW specs these plugs for a reason..

 

How can you SAY such a thing??? BMW owners OVER-ANALYZING SOMETHING?? IMPOSSIBLE!!!!! :eek:

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The more time you spend over analyzing, the less time you have to ride !!!

 

Buy the NGKs, replace the old ones and then ride your motorcycle !!!!

 

That is what I did...

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