So I just took my bike in for the 7500 mile maintenance. On the schedule, it lists changing the spark plugs, but the mechanic said that was definitely not necessary at that mileage for the bike.

Opinions?

I replaced the stock OEM plugs at 20,000 miles and noticed no difference.

* Last updated by: zxrider11 on 4/11/2012 @ 8:58 AM *

I pulled the set of plugs on my 08 @ 15800 miles, they did not look beat up at all. The mechanic said they could have gone longer. I ran my next set almost 26000 miles and the only reason I changed them was because I was feeling it must be about time. The new set gave me about 1 to 1.5 more MPG. I just looked at the 26K set and I left them in too long. The drop in MPG was a good sign. 20,000 miles would be about what I will do on my 2012.

Nice to get some more feedback guys, thanks. I wonder why they set the periodicity so short in the manual...

It is a platinum tip. Very tiny wire or center electrode. Every time it sparks, material flies off it. Like a welding rod, it eventually will be eaten away. The gap widens. Your 20K plug see the gap widen as the fresh plugged 14 literally wipes your ass is grass you do not follow simple steps like the "quote" owner's man you will pay!

29K here and runs like a raped @ss ape on the original plugs. Have new plugs, will change soon just because I feel it should be done.

This is what #4 looked like at 14K miles. carboned yes but No white. Gap looks to be without build up.

* Last updated by: Rook on 9/11/2015 @ 1:18 PM *

Rook what is the double plug and is it Laser Iridium? Does not look like it. Give CR number. All of my plugs out of my 08 with 26K on them were all gapped the same and were at the max of .35 after I pulled them out, same as when they went in. Why are you going to use the new plug? Do you think it will make a difference? My #4 plug next to yours looks about the same but the electrode was much more pointed.

Rook what is the double plug and is it Laser Iridium?

Tell ya the truth I don't know what it is. Says NGK LASER PLATINUM premium on the box. Doubt very much it is platinum for real. I went with it cuz it was something different. The part# is CR9EKPA 7785. Was ~$80 for 4 of them (I think, was a while ago that I ordered them). really didn't seem like there was a solid favorite. Not really a big issue.

These were recommended in a Bikeland thread along with a couple others.

http://www.bikeland.org/board/viewthread.php?FID=27&TID=59502

EDIT, 09/2015: It was recommended to me on this thread http://www.bikeland.org/board/viewthread.php?TID=54941&FID=27 Man it is weird to do a search and come up with threads that I participated in years ago. See post #3. This guy sounds like he knows what he's talking about so I thought I'd give them a try.

The double electrode CR9EKPA is supposed to stick into the combustion chamber farther and promote better combustion. The plug is the same length from electrodes to gasket as OEM single electrode but the center electrode on the CR9EKPA protrudes a bit more out of the end of the plug. The split side electrodes preserve the same clearance with the piston while still allowing the spark to occur another couple mm deeper into the fuel cloud. That's how it seems to me based on this guys explanation and my visual comparison of the plugs.

* Last updated by: Rook on 9/11/2015 @ 1:07 PM *

Almost kinda scary how I can dig this crap up.

So HUB is your third cousin twice removed? Thanks for the info. The fact that the box does not say LASER IRIDIUM PREMIUM says it all.

http://i149.photobucket.com/albums/s58/wazfst1tyme/Duhub.gif

Hey, 44?

Got my twice removed and then some cousin over for??? I think she's moving in?

Rookie,

Get a gander of the center electrode on the dual sided electrode plug.
Get a look at how sharp the edges are.
Get a chunk of electricity flowing, it wants to find the sharpest edge to jump from.
Get a theory like, 'for every action is the jump of the spark and hits that sharp edge, so does the spark be sparking at the sharp edge on the reaction of the action you cannot dispute.
Get a palm against a palm and run them hard against each other. That heat in the middle you can see the trail, but can feel the transfer if spark means anything is heat.
Get a spark to ground and she is going to whip some metal to shreds.
Get a gander now at that platinum gap. Do you see sharp edges or can you...
Get a feeler gauge that is at factory spec, but that gap has been eaten at so much, that gap is watt? Wider by half out of spec?
Get a blade and a half in there, you are now half a blade out of spec for how long?
Get a lane, because time is inches. I'll be burning the light fandgo faster with the fresh gap, not you timing off another half a gap to get there is time spent waiting to be lit off.

Amen! HUB I was just implying that Rook WAS on top of it just as you usually are. Was there some distant relation?

* Last updated by: 21744 on 4/14/2012 @ 12:42 PM *

Your second pic there Rook...that's a shot plug.Mine looked like that at around 20K...something like that.I replaced with factory(my 07)...at 50K...the tip were bent over like they got too hot or something...it could have been the Gumout I used a few times to clean everything up.

At 26K mine looked thiner, finer than the ones a 20K. Maybe yours at 50K, bent, were just about ready to leave, too slender to stand up to any more punishment. 20K looks about time to change. Sooner if you wish but no later.

No...not unchanged at 50k....the second set...checked at 50k.They had around 20 something thousand miles...a bit more.And they looked...fried.Melted.Overheated.Tired.

I just changed the plugs on my ZX14 and thought that I would share the experience and a few photos in case someone else wants to perform the task. The dealer indicated that the shop unit for a plug change on a ZX-14 is 4 hours (must include a coffee break). It is a fairly easy task to accomplish and the benefit is, with the body works off, you can clean and do other maintenance items. I cleaned my rad and protective rad guard screen, changed my coolant, changed my oil, installed a new battery, and wired in the lead from my battery to the region under the seat for my C-Tek battery charger.

(clean work space, printed section from service manual..... cup of tea, radio on)

With the fairing off you can see the top of the stick coil (cylinder #4)

Disconnect the electrical leads to all of the stick coils
Use a compressor and blow off / away any debris from the area, wipe, etc. to ensure that there is no chance of debris getting into the spark plug well when you pull the stick coils out.

I think that there is a bit of mystery and uneasiness surrounding the "stick coils". I hope that I can drag them out into the bright light of day and expose them for what they really are.

There is one stick coil for each spark plug. The stick coil sits on top of the spark plug. If you look at the stick coil you will see 3 ribs towards its top (these seal the spark plug well and keep out water and debris). There are 2 rows of 3 nubs toward its bottom that help center the stick coil in the spark plug well. When removing the stick coil, disconnect the electrical lead to the coil first. Do not pry up on the electrical connector. Using your thumb and the side of your pointer finger, apply a turning force as you apply upward pulling pressure. I turned the coil in one direction (about 1/8 turn) while pulling upward and the coil came loose. I reversed the direction of the turn / twist force and again pulled upward. Each time the coil came up about 25mm (1"). It was quite easy and there was no fear of pulling and having the coil suddenly pop free. The stick coils are quite long and there is just enough space to get them out of the well (and I mean just). Remove all the coils.

The spark plug well is quite deep. You will need to add an extension onto your spark plug socket. There is not much room between the top of the engine and the frame above so you first have to introduce the spark plug socket, then the extension. I found the best way was to partially insert the spark plug socket into the spark plug well (being careful not to drop it down the well and crack the porcelain of the plug and risk it falling into your cylinder when you pull the plug out) and then add the extension onto it. With sufficient length you can then lowered the spark plug socket down safely onto the spark plug. If you find that your extension comes up a wee bit short a universal will give you a little more length. You have to be careful when using universals because it is easy to create off axis pressure. The one benefit is that you can flop the top of the universal over, providing more surface area to hold onto, which make screwing the new plug in by hand a lot easier. You can see from the photo that you can get your hand in but there is not a lot of room to spare.

Use a flat blade screw driver to help separate your ratchet from your extension. Insert the blade of the screw driver between the ratchet and the extension and twist. (I like control actions and the skin on the back of my hand)

I worked on the right hand side of the bike first, removed all the coils of the 3 that are accessible from that side (#2, #3, & #4 cylinder). I removed #4 spark plug first, and installed a new plug. Then moved onto #3 and repeated the process, then #2. I could have started with #2 first, but it is better to start where you can see and work out a good procedure before working blind or by feel. Make sure when you go to install the new plugs that you firmly press the new spark plug into your spark plug socket (you do not want the plug to fall out and down into the spark plug well - damaging the plug, chipping the porcelain, and changing the spark plug's gap. If you find that your spark plug socket is not as tight as you like you can apply a piece of electrical tape to the inside face and extend it to the outer surface of the socket, then apply a band of tape around the socket for good measure because you do not want anything getting into your cylinder. Remember to check the gap of your new plugs.

With all the spark plugs installed, I applied a little silicone dielectric grease to the ribs and nubs of the stick coils and inserted them into the well holes. Make sure you feel a good connection to the top of the spark plug. Attach the electrical connections to the stick coils starting at #2 and working outward to #3 so that you do not stress or have to fight over the wiring.

On the left hand side (for cylinder #1) you will have to remove a small bracket. This side is the tightest but after polishing your routine on the right hand side you will have no problems.

My bike has just over 15,000 km ( 9,320 miles). Here is what my plugs looked like next to a new plug. I believe my manual suggested to change the plugs at 12,000km (7,457 miles) it does seem like a short life for a spark plug.... makes me remember my 2 stroke dirt bike days. I think it is better to be safe and put your faith in the manufactures recommendation of what their product requires and follow the manual. (imagine getting past by a Harley because one of your spark plugs failed - hang on.....actually even if 3 failed a ZX-14 could still take on a Hardly Dangerous) -LOL

This task may not be for everyone, but is by no means difficult.
Can anyone do it with a limited number tools - Yes
Would I do it again? - Yes
How much could you save by doing it yourself? - possible $400 (based on shop rates of $100/hr)
And the cheeky question.......Have I started the bike - Yes (purrs like a new kitten)

Hope this provides some useful knowledge,

Spyglass

* Last updated by: spyglass on 6/1/2012 @ 6:39 PM *

Excellent job documenting!
If you still have your old plugs could you please post a pic with the same composition Rook did? I want to evaluate your
erosion. See in Rooks pic he shot the plug directly on its side: you can see the erosion of the ground electrode.

Nice work. I would post in How-Tos. There is a torque value for the plugs Too I believe.

Torque - Spark Plugs: 13 N·m (1.3 kgf·m, 115 in·lb)

EDIT:09/2015
I just installed plugs and I doubt very much it is necessary to use 115 inch lbs of torque. I tightened until I felt the crush gasket was sealed and that was less than 60 inch lbs. Mine were not hard to remove after 44000 miles so I see no reason to tighten more than they had been.

* Last updated by: Rook on 9/13/2015 @ 3:42 PM *

Hagrid I do still have my old plugs. I generally keep each set of plugs and date them. This way I can compare them to the set I just installed when they are changed. It looks like Rooks photo was taken outside in daylight. I will put my macro lens on my camera (opposed to the point & shoot I used previous) and offer a better shot.

Rook good point. I should have also mentioned the spark plug gap too. It is always the little things that add the polish and make a thing shine. If this post is better suited to another area of the forum maybe a Forum Admin or Mod can move it.

Thanks,

Spyglass

still have my fresh NGK CR9EKPA sitting here. Have to change them in some day.

Nice plug change tutorial - spanks mang.

Great article about reading plugs by Kevin Cameron in the Aug '12 Cycle World

There's more to it than "just 'changing plugs'"...the mfg's want the mechanic to inspect things throughout the life of the bike.Changing plugs at 7500 or whatever may not be necessary...but getting in there to do the work,remove stuff,take the plugs out,reinstall(even if they're good...)...if anything wrong is getting by unnoticed...it stands a better chance of being caught 'early'...

Changing plugs at 7500 or whatever may not be necessary...

It takes the big boys and sits the other clowns trailering their whole plan of showing up to begin with. You show up with 20 thousand mile plugs for a dyno test, a drag meet... It shows how some of you need to sit down and play with your clown. "Whatever (may or) may not be necessary."

Really good how to Spyglass. I changed mine last week after 21k miles. I know:
At first my idle was to high so I readjusted it (about 300 rpm) but after two short rides I had to adjust it back down!!! The bike is more responsive and I get more grunt down low. Fuel economy seem to have been increased as well. Hub was right you don't wanna go racing with old plugs. From now on, it's by the book! The only thing I will be stretching is the Motul 300 V double Ester. That oil has more than 4k miles on it but the gear box is still smooth like butter. Going to take it to 5k!