Spark plug choice...

[Karate.Snoopy]

One of the reasons gap could be twice as important on our bike is it uses 2 coils for 4 spark plugs. One coil for #1 and #4 cylinder and one coil for #2 and #3 cylinder. What happens is the coil fires at TDC and the end of the exhaust stroke for each piston that is mechanically at TDC and end of exhaust stroke. In other words pistons #2 and #3 are both in the same position in the cylinder but they are at opposites in firing and exhaust. One being the end of compression and beginning of power. The other cylinder would be the end of exhaust and beginning of the intake. So the coil is firing twice as many times as a coil that is dedicated to one cylinder. Dielectrically there is more stress on the coil pack because the path for it's spark has been increased. It is more likely to create corona (with increased gap) internally and break down internally or when there is an insulation problem it may more readily take that path and not produce a strong or weak spark where we want it. The coils are looking a 2 plugs... Be careful setting the Iridiums!
Set your gap to factory specs!

:bow::bow::bow::bow:
I am thinking about pulling out the Iridiums and installing the Standard NGK's and setting the right gap.

 

[Motogiro]

Too eager at this end , I am not too mechanically savvy and a bit on the lazy end of the spectrum. Isn't there a stock spark plug set that has the correct gap off the shelf?

To reiterate: One plug is not specifically made for only one engine. The Gap is not specific to your model bike and you should always set the gap to the Bike manufacturers specifications. If you're setting gap on the Iridiums be careful of that center electrode!

 

[gocartone]

Running iridium plugs in my bike with whatever gap they came set at (have never messed with the gap on them in any of my vehicles and no problems). Last tank of gas (91 octane) was mostly highway, with some fun driving mixed in , and I averaged 50 mpg on a 150 mile trip. Coppers never seem to last long IMO.

I would like to see a test done in 5k intervals without resetting the gap (other than the initial) to see which is more conductive, iridium or copper. I'm guessing the slight conductive advantage copper has is lost in a hurry with how much faster they wear down.

 

[FZ09Bandit]

Uhm whoever here thinks that "you get more power from a plug" is not correct. it came from the factory with those plugs, designed to work with those plugs, so buy those plugs. Get OEM and don't let the salesman sale you you more expensive plugs. However, there is a difference between OEM and 2$ spark plugs, I work on engines all day everyday. Never seen one give a noticeable (albeit "feel able") difference. if it calls for IR's get iridiums. All they do is last longer. 100k on vehicles. Why are spark plugs in the mod section? LOL it's like saying different antifreeze or oil will give you more HP.

And dear god don't gap iridium plugs!

 

[FZ09Bandit]

To reiterate: One plug is not specifically made for only one engine. The Gap is not specific to your model bike and you should always set the gap to the Bike manufacturers specifications. If you're setting gap on the Iridiums be careful of that center electrode!

And the coating

Woops that's only on platinums. But yes don't funk the electrode up. Never gapped IRs. Never had a problem. I am pretty sure different NGK ir part numbers have different gaps.

 

[Motogiro]

Here's some additional info for gapping from NGK. I guess they're recommending setting the gap for your specific vehicle.

[ame=http://www.youtube.com/watch?v=lk70oyUEftY]Spark Plug Gap - NGK Spark Plugs - Tech Video - YouTube[/ame]

 

[FZ09Bandit]

"Your gap should be set for your vehicle, but we recommend you check"

 

[FinalImpact]

One of the reasons gap could be twice as important on our bike is it uses 2 coils for 4 spark plugs. One coil for #1 and #4 cylinder and one coil for #2 and #3 cylinder. What happens is the coil fires at TDC and the end of the exhaust stroke for each piston that is mechanically at TDC and end of exhaust stroke. In other words pistons #2 and #3 are both in the same position in the cylinder but they are at opposites in firing and exhaust. One being the end of compression and beginning of power. The other cylinder would be the end of exhaust and beginning of the intake. So the coil is firing twice as many times as a coil that is dedicated to one cylinder. Dielectrically there is more stress on the coil pack because the path for it's spark has been increased. It is more likely to create corona (with increased gap) internally and break down internally or when there is an insulation problem it may more readily take that path and not produce a strong or weak spark where we want it. The coils are looking a 2 plugs... Be careful setting the Iridiums!
Set your gap to factory specs!

What it really lacks by design is saturation time. At 14,000 RPM that doesn't leave much time with "waste spark system" so its very likely coil output energy is weak at high RPM. Remember its not just a spark and there is current factor. Hence the reason the gap is so critical.

Just an observation but Yama may have learned something over the years as the 09 does not use the "K" plug with the double ground strap side fire electrode. Also NGK calls for less gap on the CR9E single ground strap plug (conventional plug) 0.028" vs 0.032" on the K version.
POINT; the CR9EK is gapped at 0.032" The spec for our bike is 0.6–0.7 mm (0.024–0.028 in). be sure to correct this before installing your plugs!

EDIT:
I'm curious if the ECM/Coil packs would be OK without the resistor Plug CAP or would this impair them or something like the instrument cluster from the EMI noise emitted either radiant or back into the connecting wires? I might remove the interanl resistor in the cap and see what happens! Why you ask? Because I can feel when the plug wires get loose in the caps. Not to thread derail, but I'm curious if there is anything to be gained by removing the inline resistor to get more energy to the plug?

The Downside:
The resistor cap and plug add 10K and 5K of resistance. This drops the current delivered to the plug. By reducing the current, there is less electrical noise emitted by the ignition system, more heat generated by the resistance and less energy delivered to the plug (think in terms of current here). But its very likely the load in watts goes down with these resistors in place and the ECM or Coils may lack the balls to run without the series resistors. So this could all go horrible wrong and lead to a misfire. You see what I don't know is if the ECU and Coil packs have the energy to run w/out that 10K resistor plug cap?

If this was purely from a noise suppression iussue it seems a better choice would have been a shielded plug wire as the CAP and plug are shielded (EMI wise) by being recessed in the head. I just don't see why they did both? The head is canceling the radiant EMI however there is an exposed wire that's acting like an antenna as its a solid core non-suppression wire tossing out EMI noise everywhere. So it almost seems like they did it for the sake of keeping the energy demand low.

I guess my point is the coil output is so feeble with a mere 0.028" max gap that it needs all the energy it can muster at the plugs gap. Hint most HEI coils fire plugs gapped at 0.50" or better these days so this seems weak!
Thoughts anyone?

Other things of interest:
NGK DENSO BOSCH BRISK SPARK PLUG TEST - YouTube

Some thoughts on Ethonal based fuel.
NGK Spark Plugs USA

Read up on this:
NGK Spark Plugs USA
NGK sparkplugs information and specification

08 and lower
CR9EK // 4548 // OEM Gap = 0.032" // Iriduim # CR9EIX gap 0.032"

09
CR9E // 6263 // OEM Gap = 0.028" // Iriduim # CR9EIX gap 0.028" // single ground wire

While here lets throw Torque Spec:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)

 

[FinalImpact]

Very interesting from an Aviation thread....

Missing picture is is showing the internal resistor which is breaking down and failing. See link below if this peaks your interest.
Excerpt: <<PASTE>>
As you can see in this photo of a two month old Champion RHB32S fine-wire spark plug with only 110 hours in service, there is corrosion on the conductive surfaces. When it was new two months ago, the resistance was normal, about 1500 ohms. But today, this spark plug’s resistance is over 12,000 ohms! That means some of the spark energy isn’t passing through to the electrodes. This spark plug was causing elevated CHT’s in the affected cylinder. Installing new spark plugs resolved the CHT problem, and stopped the intermittent vibration problems at low rpm.

Note: CHT is Cylinder Head Temperature....

Full link: Spark plugs. Why you should check yours, today! | Platinum Aviation Blog

Just thought I would share. We are not alone. In this thread there is mention of why those resistors are in there. It's about the field collapsing and reducing the spark plugs life as well as noise suppression.

I'm going to take this up in another thread as it now has my curiosity!
http://www.600riders.com/forum/fz6-technical/48874-cure-bad-vibrations-spark-plug-caps.html

 

[Motogiro]

Very interesting from an Aviation thread....

Missing picture is is showing the internal resistor which is breaking down and failing. See link below if this peaks your interest.
Excerpt: <<PASTE>>
As you can see in this photo of a two month old Champion RHB32S fine-wire spark plug with only 110 hours in service, there is corrosion on the conductive surfaces. When it was new two months ago, the resistance was normal, about 1500 ohms. But today, this spark plug’s resistance is over 12,000 ohms! That means some of the spark energy isn’t passing through to the electrodes. This spark plug was causing elevated CHT’s in the affected cylinder. Installing new spark plugs resolved the CHT problem, and stopped the intermittent vibration problems at low rpm.

Note: CHT is Cylinder Head Temperature....

Full link: Spark plugs. Why you should check yours, today! | Platinum Aviation Blog

Just thought I would share. We are not alone. In this thread there is mention of why those resistors are in there. It's about the field collapsing and reducing the spark plugs life as well as noise suppression.

I'm going to take this up in another thread as it now has my curiosity!
http://www.600riders.com/forum/fz6-technical/48874-cure-bad-vibrations-spark-plug-caps.html

Yes I agree pretty much with what you're expressing and the one thought that comes to mind with the coil packs is what you've already expressed. Designing a pack that will deliver an effective spark from 1 rpm to 14000 rpm has to be pretty interesting in that as the frequency increases the *Q of the coil is constantly changing thus the performance changes. At 14,000 rpm we have essentially a 7 Khz** signal out of the ECU that is driving the primary winding as well as hopefully a 7 Khz secondary spark. I'm betting engineers had to design a coil pack for economic feasibility as well as weight and performance. For instance if I want to up the secondary voltage with increased secondary coil winding what happens to the Q on the secondary? It changes. So I think they've found a happy medium for design. Naturally the impedance, front and back, are going to go through a myriad of changes. They possibly have software that deals with this ever changing impedance to keep the spark at optimal performance. So we're talking about the ECU and the coil packs operating into the radio frequency spectrum! Because of that we'll have EM fields building and collapsing in a pretty dynamic frequency spectrum. I think if I had to design an ECU output and coil pack I would have to consider minimal performance parameters where it was hardest to develop current and voltages for secondary voltage and then the rest would be Apple Pie! :BLAA: When we speak of plug resistor and RF suppression in present design, this might make more sense.

I think as technology continues to grow we may see more optical coupling for sensors and drivers that may help increase performance and reliability.

* Q factor - Wikipedia, the free encyclopedia
** Based on the FZ6 coil packs firing on TDC of a piston, on power and end of exhaust strokes.

 

[motojoe122]

I concur, Doctor:BLAA:

 

[darth47]

Purely because the plugs are a bastard to change, I went with long-life Iridiums.

No obvious performance difference noted, but the Iridium says it's good for 100 000kms, so if I even get half of that, I'm happy. (and probably wont have to change my plugs ever again!)

I used to change my plugs every 5000kms on my Z750, CB750 etc!

Cheers,
Rick

The same reason i'm going for NGK Iridium plugs... longetivity! I'm sure I wouldn't notice a difference in performance cos I don't race, just commute!

 

[polydoc]

I recently installed ngk iridium's (without the yamaha tool, PITA!!!) and my bike no doubt runs much better. Smoother accel and deceleration, engine braking is smoother etc... it is not a placebo effect. Just a week before i drilled the baffles and noticed some performance gains from that, but since the iridiums i feels like my bike is running just like its supposed to. I would highly recommend them, i bought them off amazon prime for 6.50 a piece, and boy was it worth it.

 

[Def]

Uhm whoever here thinks that "you get more power from a plug" is not correct. it came from the factory with those plugs, designed to work with those plugs, so buy those plugs. Get OEM and don't let the salesman sale you you more expensive plugs. However, there is a difference between OEM and 2$ spark plugs, I work on engines all day everyday. Never seen one give a noticeable (albeit "feel able") difference. if it calls for IR's get iridiums. All they do is last longer. 100k on vehicles. Why are spark plugs in the mod section? LOL it's like saying different antifreeze or oil will give you more HP.

And dear god don't gap iridium plugs!

+1! I put a new set of OEM's and really didn't find them very difficult to change.

 

[TownsendsFJR1300]

Uhm whoever here thinks that "you get more power from a plug" is not correct. it came from the factory with those plugs, designed to work with those plugs, so buy those plugs. Get OEM and don't let the salesman sale you you more expensive plugs. However, there is a difference between OEM and 2$ spark plugs, I work on engines all day everyday. Never seen one give a noticeable (albeit "feel able") difference. if it calls for IR's get iridiums. All they do is last longer. 100k on vehicles. Why are spark plugs in the mod section? LOL it's like saying different antifreeze or oil will give you more HP.

And dear god don't gap iridium plugs!

Spark plugs, especially in two strokes, new ones do indeed often make a difference in performance, even if you clean, re-gap, etc the old plugs.. Just a very wide, worn out gap will make a difference, especially in much smaller (weedeater, type) engines..

And yes, you can indeed re-gap iridiums. Go to the NGK site, its posted there. Watch the video from NGK, it goes into more detail re gapping Iridiums: NGK Spark Plugs USA

I checked my iridiums before installation, one of 4 was off by .001" so I didn't screw with it. I did NOT notice any performance difference but I don't have to change them again anytime soon...

Just use a WIRE FEELER gauge to check the setting and do you adjusting by bending the ground with the feeler gap tool.


Without starting an oil thread, full synthetic oil will give more protection than regular dino oil, so I have to disagree there as well. Better protection will indeed, free up horsepower... Its been proven on a dyno (for an auto in this case) before and after an oil change from Dino to Royal Purple (on "Horsepower TV", Spike TV)

 

[Marcelor73]

Uhm whoever here thinks that "you get more power from a plug" is not correct. it came from the factory with those plugs, designed to work with those plugs, so buy those plugs. Get OEM and don't let the salesman sale you you more expensive plugs. However, there is a difference between OEM and 2$ spark plugs, I work on engines all day everyday. Never seen one give a noticeable (albeit "feel able") difference. if it calls for IR's get iridiums. All they do is last longer. 100k on vehicles. Why are spark plugs in the mod section? LOL it's like saying different antifreeze or oil will give you more HP.

And dear god don't gap iridium plugs!

If we all were to follow your logic, then we shouldn't mod at all.

- why change a headlight bulb if the manufacturer decided on the best one? Why revalve forks if they're the best they can be from factory? Why use a different tire brand?

The manufacturers do NOT use the absolute best parts. They use what works well and what they can get for a certain price is order to be able to sell the bike for a certain price.

In most cases there's room for improvement with aftermarket products and spark plugs are no exception.

 

[FZ09Bandit]

If we all were to follow your logic, then we shouldn't mod at all.

- why change a headlight bulb if the manufacturer decided on the best one? Why revalve forks if they're the best they can be from factory? Why use a different tire brand?

The manufacturers do NOT use the absolute best parts. They use what works well and what they can get for a certain price is order to be able to sell the bike for a certain price.

In most cases there's room for improvement with aftermarket products and spark plugs are no exception.

I'm sorry, you must not understand. I work on vehicles for a living. We get one in here because customers replace spark plugs, now it runs worse. I pull the cheap after market plugs out and put in good ol factory plugs. 99% of the time it clears right up. Had a Hyundai with bosches in them yesterday running like crap, put ngks In there and boom ran like a sowing machine.

I went to the DSM, EVO, GTR shoot out last august and looked at 8-9 second cars. Care to know how many where running factory plugs? All of them

And besides aftermarket is a irrelevant term for spark plugs. Just about one brand per car company, bosche is more of a German car plug where as AC Delco are for gmc and by no means are they :cheap: at 8$ a plug LOL

 

[Motogiro]

If we all were to follow your logic, then we shouldn't mod at all.

- why change a headlight bulb if the manufacturer decided on the best one? Why revalve forks if they're the best they can be from factory? Why use a different tire brand?

The manufacturers do NOT use the absolute best parts. They use what works well and what they can get for a certain price is order to be able to sell the bike for a certain price.

In most cases there's room for improvement with aftermarket products and spark plugs are no exception.

I'm sorry, you must not understand. I work on vehicles for a living. We get one in here because customers replace spark plugs, now it runs worse. I pull the cheap after market plugs out and put in good ol factory plugs. 99% of the time it clears right up. Had a Hyundai with bosches in them yesterday running like crap, put ngks In there and boom ran like a sowing machine.

I went to the DSM, EVO, GTR shoot out last august and looked at 8-9 second cars. Care to know how many where running factory plugs? All of them

And besides aftermarket is a irrelevant term for spark plugs. Just about one brand per car company, bosche is more of a German car plug where as AC Delco are for gmc and by no means are they :cheap: at 8$ a plug LOL

Remember that while we are talking about brand, the plug gap should be checked and set to the factory recommendation for the the vehicle and not the pre-set gap the plug comes with. That pre-set gap of the spark plug will allow the vehicle to run but is not always the gap required for that specific vehicle to run efficiently.
Here's an interesting thought/question: If you checked the plug gap on a new vehicle will the gap be what the factory service manual calls out or will it be a gap that is pre-set by the plug supplier?

I think regardless of the plug design or manufacturer, the gap is pretty important toward the performance of a vehicle through the many considerations of how internal combustion works today. Compression ratio ,heat range ,fuel grade, high tension wire grade and connection, rpm etc.

I swapped out to the NGK Iridiums. I set the gap on them to my factory spec and although I can't tell you there's more horse power I do get better mileage. I did not however check the OEM plug to see if the gap was set to factory spec, which it may not have been.

 

[TownsendsFJR1300]

I'm sorry, you must not understand. I work on vehicles for a living. We get one in here because customers replace spark plugs, now it runs worse. I pull the cheap after market plugs out and put in good ol factory plugs. 99% of the time it clears right up. Had a Hyundai with bosches in them yesterday running like crap, put ngks In there and boom ran like a sowing machine.

I went to the DSM, EVO, GTR shoot out last august and looked at 8-9 second cars. Care to know how many where running factory plugs? All of them

And besides aftermarket is a irrelevant term for spark plugs. Just about one brand per car company, bosche is more of a German car plug where as AC Delco are for gmc and by no means are they :cheap: at 8$ a plug LOL

You nailed it right there!

They put in some cheap, spark plugs and it ran bad.

If you put piss poor fuel in your vehicle that requires premium, bad things may/likely happen..

Iridiums, at least IMHO are a step up and are still factory NGK's which Yamaha initially installed.

Yamaha also put regular roller bearings in the steering head (as does the Honda Goldwing) as its cheaper. The Tappered bearings give more surface area (better overall) and for the Goldwing, which is inherently known for a de-cell wobble after x # of miles WILL indeed cure it.

I'm one to put mostly OEM parts on my bike (or any vehicle I own) however there are cases (the above mentioned steering head bearings) where the factory skimps to save money, a larger profit margin.. IE, EVERY Yamaha FJR every produced, does NOT have a helmet lock . Its a top of the line sport touring bike but there's no place to hang a helmet, WTF??? Many BMW's are the same. My 07 FZ6 (1/3 the price) comes from the factory with a helmet lock..

I concur with Cliff compleatly re the gap.

As you know the gap opens as the plug wears, so I set mine on the tight side of spec's.. Another member here found his plug gap worn way beyond spec's, (ran somewhat crappy) and of course changed or re-gapped (I don't remember) and it ran much better after that...

 

[FZ09Bandit]

^ that's what I have Been getting at lol. I'm not taking about anything else BUT spark plugs. People put words in people's mouths too often. I used my car as an example, don't put cheap knock offs in it and it will last forever.