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Read My Spark Plugs

The electrodes on all four look pretty good. Generally, if they all look the same, you're in good shape. It's usually only one or two that foul and you'd easily be able to see that in relation to the ones that didn't foul.

As for the porcelain with the charring on it. That is likely due to a poorly seated ignition cable/wire that is causing some arching between the cable and the spark plug.

When you put the ignition cables back on, they make a little palpable click as they seat to the spark plug. If you don't feel this, then you aren't seated properly and you need to try again or replace the cable.

Hope that helps!:thumbup:
 
Say Nate, how many miles did you have on your plugs? I just changed mine out a couple of weeks ago for the first time. Had over 20,000 miles on them and had absolutley no issues whatsoever with them.

 
I put about 13,000 on those plugs. How many times did you change your air filter during that 20,000 and do you have any power mods? My bike is all stock in the power department. I was not under the impression that my plugs were "having any issues" I just thought I'd post this pics...I don't remmeber noticing a difference in performance after changing them out.
 
I put about 13,000 on those plugs. How many times did you change your air filter during that 20,000 and do you have any power mods? My bike is all stock in the power department. I was not under the impression that my plugs were \"having any issues\" I just thought I'd post this pics...I don't remmeber noticing a difference in performance after changing them out.

Changed my airfilter one time, and upgraded to an K&N filter around 15,000 miles I think.

Power Mod - Just aftermarket exhaust if you consider that power.

I did upgrade my plugs to the Iridium plugs, but I have not noticed any difference between the two plugs as far as performance. The only difference I hope I'll get between the stock and my new plugs is that I should get over 30,000 miles on these babies.
 
looks like you could use to lean the bike out a bit, those look a bit rich to me, but as said before they are very consistent which is good. you could try the CO settings if you don't have a PCIII.
 
looks like you could use to lean the bike out a bit, those look a bit rich to me, but as said before they are very consistent which is good. you could try the CO settings if you don't have a PCIII.

I was thinking the same thing, just a little be fat. That said I've never pulled plugs in an FZ before.

I don't recall that the interval is for changing, 12K?
 
If you'd been cruising on the highway, and had hit the killswitch, then pulled the clutch in, and coasted to the side of the road, and without ever starting the bike again, removed the plugs, then yes, those would be a little rich looking.

Because that's how you're supposed to pull plugs to read them.

But since what you probably did was to ride somewhere, come home, putt along your neighborhood streets to your house, pull into the driveway and then shut the bike off, you're not getting a fair plug reading. Idle and low speed is going to be rich, which is what your plugs indicate.

So they're fine.
 
I think the interval is 8,000 miles

If you'd been cruising on the highway, and had hit the killswitch, then pulled the clutch in, and coasted to the side of the road, and without ever starting the bike again, removed the plugs, then yes, those would be a little rich looking.

Because that's how you're supposed to pull plugs to read them.

But since what you probably did was to ride somewhere, come home, putt along your neighborhood streets to your house, pull into the driveway and then shut the bike off, you're not getting a fair plug reading. Idle and low speed is going to be rich, which is what your plugs indicate.

So they're fine.

Yeah, I'm learning all about this now. :rockon: I would not have guess their appearance would change so easily.
 
I was thinking the same thing, just a little be fat. That said I've never pulled plugs in an FZ before.

I don't recall that the interval is for changing, 12K?


Also if you have never pulled the plugs before i would put in new ones and see what those look like at the next change. they may have blackened before your dyno tune.
 
1 question is there any easier way to remove the plugs?

man i did it and was A PITA manual said remove lower radiator bolt and thats it

no room for nothing :(
 
1 question is there any easier way to remove the plugs?

man i did it and was A PITA manual said remove lower radiator bolt and thats it

no room for nothing :(

I think the 2007 modlels and up are much easier to replace, as the spacing from the radiator has opened up a bit more from the later models.
 
I think the 2007 modlels and up are much easier to replace, as the spacing from the radiator has opened up a bit more from the later models.

This is true, plus the fairing doesn't reach nearly as far down the sides thus creating more workspace (without removing the fairing).

There are a couple threads here about plug removal, tips, and do's/don'ts that people have run into. The biggest thing is to be SURE there is no debris in the plug wells BEFORE you pull the plugs out. Once that grime is in the combustion chamber, you're in a pickle!
 
I think the manual says something along the lines of check every 8k miles replace if neccesary. Getting 16k out of a set shouldn't be too hard.. especially if you upgrade to iridium plugs for a few more bucks. Here is a link to a great write up on how to change plugs from the "other" forum.

Replacing your Spark plugs in 20mins

P.S. Removing the lower radiator mount will make your life alot easier.
 
I would say the plugs look fine, yes they are darker, but there is no real amount of soot built up. The arcing on the ceramic is common if you get moisture down in to the sparkplug well, happened on my cars before. You can stop it by putting a dab of dielectric grease on the threaded stud before you install the plugs. This will keep moisture out of the electrical contact area and help make sure no arcing occurs. :noworries:
 
Some questions:

1) How many miles do you have on those plugs? Might have been over-due for a change.
2) What is your gas mileage
3) Any problem with bike operation, ie. hard to start when hot or cold, slow acceleration, etc. etc.?
4) Any foul smell on your exhaust fumes when hot?
5) What octane fuel do you use?

Just by looking at the pic, I'd say just change it and forget about it. If there's a deterioration in engine performance, only then you might wanna think about doing some adjustments and/or a complete tune-up. Of course there's no harm in following normal maintenance schedule and check-up.
 
Well I finally changed out my plugs after 12,000km's (7456miles) on the odometer. Not looking too bad....

15330d1239767868-read-my-spark-plugs-dp_090412_19.jpg
 
Well I finally changed out my plugs after 12,000km's (7456miles) on the odometer. Not looking too bad....

15330d1239767868-read-my-spark-plugs-dp_090412_19.jpg

those look good, mine actually looked the exact same when I replaced them for the first time at 20k km (yeah I'm lazy...). I put in the NGK Iridium's so I don't have to replace them again anytime soon, cause what a pain in the...
 
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