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Iridium plugs installed

I would like to do this as well but, the manual says the CR9EK with a gap of .024 to .028 and the CR9EIX has a gap of .032.

So did you have to change the gap of the IX or did you leave it as is?

Does it matter?

You're not supposed to touch the gap on an iridium (not sure why)... but I do know that iridiums use less voltage to spark than any other plug. They also claim to have a hotter spark... Maybe that has something to do with the larger gap... So, I just pulled them out of the box and screwed them in... They have been flawless for 1000km now since I installed them... The bike still idles better and is smoother all round...
 
Thanks for the thread Richard :thumbup:

I got the same plugs -quicke delivery too- and put them in yesterday... I did not feel any noticeable difference while riding or at idle, but the install was quick and easy (except for plug # 1, which took a little more time).

Old plugs did not look bad though... just the normal brownish color.
 
Sounds good to me, it's time for me to change my plugs as well. Are we sure that the difference in gap won't make a difference in our bikes? I know that normally this is a very important detail when changing plugs on cars.
 
I'm due to change mine again soon. I am still thinking that I will stick with the NGK's, but sounds like these work pretty well. Is there a link on them? I'm going to look it up myself anyway.
 
Also what is the advantage of the Iridium CR9EIX over the Standard CR9EX plugs? I know Iridium is used in higher performance cars because they use less electricity to spark and spark hotter --> better performance. I guess my real question is related to maintenance schedule. Do you need to change them less often?
 
I'm due to change mine again soon. I am still thinking that I will stick with the NGK's, but sounds like these work pretty well. Is there a link on them? I'm going to look it up myself anyway.

These are made by NGK also. They are Iridium plugs though, which is supposedly a step up from our stock plugs.
 
These are made by NGK also. They are Iridium plugs though, which is supposedly a step up from our stock plugs.

Really? Had no idea that NGK made those. Is the name brand NGK? Or is it under another name.

Just did a Google search and found them. I think I am going to order some.
 
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Really? Had no idea that NGK made those. Is the name brand NGK? Or is it under another name.

I'm not really sure I understand your question GuitarMan. The brand name is NGK. The model name is CR9EIX. Stock NGK plug is CR9EX (notice there is no "I" in the name).
 
you should never touch or check the gap on a platnium or irrridium plug, it damages the electrode and reduces life expectancy. If running platniums already do changes at same length.
 
Verify... there is a grounding difference between the plugs. Online images show the CR9EX plugs have the multi-ground electrode placed to the side of the center electrode and the CR9EIX has a single-ground electrode placed below as on a traditional plug.

Also I cannot imagine our plugs require a terminal nut?
 
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You're not supposed to touch the gap on an iridium (not sure why)... but I do know that iridiums use less voltage to spark than any other plug. They also claim to have a hotter spark... Maybe that has something to do with the larger gap... So, I just pulled them out of the box and screwed them in... They have been flawless for 1000km now since I installed them... The bike still idles better and is smoother all round...

Very cool, Thanks.
 
Just installed a set myself. It is well worth the money. I ordered mine through the local auto parts store (Advance Auto Parts) they had them next day and I paid around $7.50 a piece and did not have to pay any shipping costs. :thumbup:
 
i run denso iridium plugs in my car and really noticed the difference. i think the CR9EIX alternative is the IU27 and from the research i did before splashing out on the plugs for my car denso give better power gains.

denso iridium

information
 
You're not supposed to touch the gap on an iridium (not sure why)... but I do know that iridiums use less voltage to spark than any other plug. They also claim to have a hotter spark... Maybe that has something to do with the larger gap... So, I just pulled them out of the box and screwed them in... They have been flawless for 1000km now since I installed them... The bike still idles better and is smoother all round...

any infos about this post?

I'm planning to buy denso IU27A for my 2005 and that plug's gap is 0.9 mm (0,035 in) and way wider than stock. What should I do?

denso says same thing:
DENSO SPARK PLUGS - Basic Knowledge

denso specs

info for denso IU27A: "Slant electrode, No U-Groove, No taper cut"
DENSO SPARK PLUGS - Iridium power

info about denso iridium power plugs:
DENSO SPARK PLUGS - Iridium power general info
 
any infos about this post?

I'm planning to buy denso IU27A for my 2005 and that plug's gap is 0.9 mm (0,035 in) and way wider than stock. What should I do?

denso says same thing:
DENSO SPARK PLUGS - Basic Knowledge

denso specs

info for denso IU27A: "Slant electrode, No U-Groove, No taper cut"
DENSO SPARK PLUGS - Iridium power

info about denso iridium power plugs:
DENSO SPARK PLUGS - Iridium power general info

Ideally, they should be factory set if you buy them for our particular model. Double check the plug gap with a feeler gauge, however.
 
Gap to bikes spec or your asking trouble. Verify gap with wire (round) gauges only. Flats can damage the precious metal plugs.

Other than reducing plug maintenance intervals, most of that info is just sales pitch.

It was laws and regulations that brought about changes which made manufacturers build cages that could go at least 50 - 75,000 miles before failure impacts vehicle emissions.
 
thanks for all answers. I asked directly denso via email:

Subject: * * * *Correct spark plug selection and gapping

Hello, I'm a 2005 Yamaha FZ6 Fazer owner and I want to switch spark plugs from NGK to DENSO iridium.

DENSO's website suggests IU27A to me and that plug's gap is 0.9 mm but Yamaha owner manual says 0.7 mm for CR9EK. I'm a bit confused, should I re-gap the IU27A plugs?

Also, is IU27 applicable for my ride? thank you.
Dear mr Akman,

Thank you for contacting us.

The spark plug gap recommended by the OEM (by Yamaha in this case) is based on the ignition coil voltage (smaller gap is lower required voltage) and the ignitability (ability to ignite the air-fuel mix, bigger gap is more space for the flame to grow).
The centre electrode of the Iridium Power plug is much smaller than the standard Nickel plug (Ø 0.4 mm vs. 2.5 mm).
A smaller electrode means more concentrated electric field, which means a lower required voltage.
The Iridium Power spark plug will have a similar required voltage as the original Nickel plug, but Iridium Power will give better spark.

So you do not need to modify the gap.
If you do modify the gap, there is a risk of damaging the electrodes.

The IU27A is the correct Iridium Power spark plug for your motorcycle.
One of our colleagues uses them in his FZ6 Fazer, and he is very happy about them.

regards,

Wouter Knol
Application Engineer
 
Interesting...
But there is more to it than that. It is an element but it is not the defining element as the Air Fuel Ratio and compression ratio are also a factor. As the compression goes up it takes more spark energy to ignite it. This bike has a decent amount of compression.
To light that mixture they have choices; increase potential energy output from the waste spark ignition, decrease the gap, richen the AFR or the lessor extent, reduce the firing contact surface area of the plugs eletrode and ground strap.

Maybe im reading it wrong but it seems like the comments posted have contradiction.... ?

Go ahead and run them and lets see how it goes and how long it goes!
 
NGK's video procedure re-gapping:
NGK Spark Plugs


Reading between the lines of your post/contact with Denso, quote: "So you do not need to modify the gap".

That does not mean to NOT check the gap but make sure its set appropriately (just don't set it outside of spec's).
 
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