adamyorkie
Junior Member
Are they worth the extra pennies? Has anyone fit them to their FZ6?
There was a spark plug poll a while back.
I do use iridiums in my bike. I also set them to the specified gap which many people don't. Gap is important because the secondary voltage of the coil in the vehicle is what determines that gap. Here's a link to a test and it looks like the iridium is superior in it's compressed atmosphere state where a spark plug lives.
http://www.600riders.com/forum/showpost.php?p=496479&postcount=26
Set your plug to the specified gap for your vehicle and yes NGK recommends you set your iridium plugs to the vehicle spec.
[ame="http://www.youtube.com/watch?v=lk70oyUEftY"]Spark Plug Gap - NGK Spark Plugs - Tech Video - YouTube[/ame]
I do use iridiums in my bike. I also set them to the specified gap which many people don't. Gap is important because the secondary voltage of the coil in the vehicle is what determines that gap. Here's a link to a test and it looks like the iridium is superior in it's compressed atmosphere state where a spark plug lives.
http://www.600riders.com/forum/showpost.php?p=496479&postcount=26
Set your plug to the specified gap for your vehicle and yes NGK recommends you set your iridium plugs to the vehicle spec.
[ame="http://www.youtube.com/watch?v=lk70oyUEftY"]Spark Plug Gap - NGK Spark Plugs - Tech Video - YouTube[/ame]
ChanceCoats123
Junior Member
I'm probably going with iridiums when I change plugs (which I'm probably due for), and gapping plugs correctly is very important. A set voltage (like that provided by the ignition coil) can only breakdown a certain length of air. And when plugs are incorrectly gapped (too wide) this air gap sometimes isn't broken down. Alternatively, if the gap is too small, voltage is wasted and a larger spark could have occurred resulting in an incomplete burn.
FZ09Bandit
�� Paramedic ��
http://www.600riders.com/forum/fz6-...6-spark-plug-choice.html?highlight=spark+plug
Read at your own peril especially the last page
Read at your own peril especially the last page
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It does look like the iridium plug has other superior qualities other than longer life when exposed to increased atmosphere over standard design plugs.
[ame="http://www.youtube.com/watch?v=wbuGpJWNX1M"]iridium spark plugs testing bmwservice.livejournal.com - YouTube[/ame]
[ame="http://www.youtube.com/watch?v=wbuGpJWNX1M"]iridium spark plugs testing bmwservice.livejournal.com - YouTube[/ame]
Cliff's most recent video post shows why plugs appear to dry fire in the air but fail to fire under the load of compression. Added load asks more of the ignition system and plug.
The plugs gap is also a factor of the engines compression ratio. As the C/R goes up, the gap often times goes down.
Adding to that:
The AFR changes how much energy is needed to jump a gap under the load of compression. Although a lean AFR can pre-ignite, its also harder to light and burn evenly compared to rich charge.
Also without a knock sensor, the FZ is being held back in the ignition advance department to protect it. As such it holds a very conservative advance curve so it can run on cheap pump gas and not damage itself.
adamyorkie
Junior Member
I found somewhere that sold the iridiums for only £3 more for all 4 so have fit, which I am now pleased I don't have to look at them for 24000 miles as they are a hassle to get to!! Well worth it for that, but don't notice any difference in ride quality, will post on fuel economy differences after a couple of tanks
I replaced my stockers with iridiums at about 8,000 miles and really didn't feel any diference.
The price was slightly higher (not a lot at all) and they shouldn't need replacement for a very long time (if ever).
One extra spark plug change you don't have do (not counting bloody knuckles and the joy of changing them, they've already paid for themselves.
A no brainer as far as I'm concerned. :thumbup:
The price was slightly higher (not a lot at all) and they shouldn't need replacement for a very long time (if ever).
One extra spark plug change you don't have do (not counting bloody knuckles and the joy of changing them, they've already paid for themselves.
A no brainer as far as I'm concerned. :thumbup:
ChanceCoats123
Junior Member
My plugs are in need of a change since they are originals with about 13.5k miles on them and I have a four pack of iridiums waiting for me at home.
adamyorkie
Junior Member
Hunts Motorcycles in Manchester, I think they will post out as well.
You probably can find them on ebay cheaper, paid £40 for all 4. I use Hunts all the time so would rather pay a bit more and no I have easy come back.
You probably can find them on ebay cheaper, paid £40 for all 4. I use Hunts all the time so would rather pay a bit more and no I have easy come back.
adamyorkie
Junior Member
after a few tanks I am averaging an additional 2 miles per gallon since the change. So well worth spending the extra little bit.
For that little difference in price I would run them again.
I ran a set in my FZ6, at first the bike idled and ran much smoother but towards the end they didn't seem to be much of an improvement. I put OEM back in and they seemed to be about the same. I did not gap as Cliff suggested which may be why they didn't seem to last as well. I'm coming up on a plug change on my current bike and will probably put them in it after I properly gap them (thanks Cliff).
I ran a set in my FZ6, at first the bike idled and ran much smoother but towards the end they didn't seem to be much of an improvement. I put OEM back in and they seemed to be about the same. I did not gap as Cliff suggested which may be why they didn't seem to last as well. I'm coming up on a plug change on my current bike and will probably put them in it after I properly gap them (thanks Cliff).
When I installed mine, I didn't notice any difference to speak of. I think member "Red Wasp" was about the only one to have some issues with them(may be wrong).
Overall, from my experiance and reading others, they easily pay for themselves in the much longer life span vs OEM plugs.
How to gap iridium plugs; [ame]http://www.youtube.com/watch?v=lk70oyUEftY[/ame]
How many miles did you have on your iridiums before you noticed degradation AL?
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ChanceCoats123
Junior Member
I would bet that your trouble with the first set had everything to do with the gap. The plugs were probably close to the upper limit at the start and ended up past the limit giving you poor performance.
I'm changing my plugs (for iridiums) over the winter and I'm going to set the gaps at the bottom end of the spectrum. This is so that as the electrode slowly recedes, the gap will still be within spec.
Seems like I have 8 to 12 thousand, I was checking the valve clearances and wanted to replace while they were easy to get to. They didn't look bad at all and I could have probably re-used them. I was in the local dealer and all they had was a set of OEM so that is what I put in. The biggest difference I have noticed when replacing plugs was when I put the Iridum's in. Not a big difference but a noticably smoother idle. I guess with modern ignition and fuel injection systems engines run much better than they used to. My old Fiat 850 Spyder needed a tune up or something almost every Saturday! My FZ6 just ran and ran and ran. Lots of improvements over the years.
Interesting!!
And lastly , do you remember checking the gap at all or just putting them in?
I checked mine before hand, one was tight by .001" within spec, so I didn't screw with it. And I honestly don't remember about the idle getting smoother or not (may have).
I was expecting some very noticable differences, but really didn't notice any (but my stockers still looked new, nice and clean burning, about 8 or 10,000 mile on them).
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^^ Sounds like the valve adjustment ** may also have been ** a contributing factor to smooth idle. It all adds up!
Anyone notice in 2009 Yamaha went with the CR9E single ground strap? Bike seems very happy with these. RockAuto even carries them for $3.50 a plug! lol
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