Just changed the spark plugs on the FZ6 and...

[bluremi]

...one of them does not look like the others:



This is after 12.5k miles. What does the white residue on the #1 spark plug indicate? It's on the bolt rather than on the head, and it's not powdery/rubbing off on my hands.


For posterity, this was easily done following the instructions on How to: Replace your sparkplugs in 20 minutes - Sportbikes.net

Didn't unscrew the radiator or anything. Whole job took a little under 1 hr with a few breaks to stretch my knees and drink my beer.

 

[TownsendsFJR1300]

It just got some moisture got under the cap, normal...


That little hole on the left side of the cylinder, that's the drain should water get in there. Your plugs reside just beyond that lil hole. Some dilectric grease on the spark plug caps help seal it and make installation MUCH easier..

A little shot of air, to make sure its clear wouldn't hurt..

 

[Love@FirstRide]

did you notice a difference with the new plugs on the bike?

 

[VEGASRIDER]

Just for numbers, I replaced my originals at 20k miles. Not because of failure but because I was worried that I was pushing the limits of the plugs to a point that it may fail. Then I replaced them with Iridiums and logged over 50k miles on them. Replaced them for the same reason, could have gotten more miles out of them but the heads were off on the bike so it was a no brainer to replace them at that time.

 

[Z3R0_zhift]

Ever tried keeping the old plugs and reuse them in case of emergency? A mech use to tell me if the plug are just burnt with carbon near the tip,we can use polish it back to chrome and reuse it as spare. Just check your caps time to time whether there's gaps,especially if you encounter heavy rain or floods. Perhaps just your plugs got slightly corroded like townsend says.

Sent from my GT-N7105 using Tapatalk

 

[TownsendsFJR1300]

Ever tried keeping the old plugs and reuse them in case of emergency? A mech use to tell me if the plug are just burnt with carbon near the tip,we can use polish it back to chrome and reuse it as spare. Just check your caps time to time whether there's gaps,especially if you encounter heavy rain or floods. Perhaps just your plugs got slightly corroded like townsend says.

Sent from my GT-N7105 using Tapatalk

Keeping at least ONE good one (at least in your tool box) expedites if your checking for spark(possible issues).

No pulling plugs, simply pull a cap, plug in your test plug, ground and check..

You may still have a bad plug, but you KNOW you coils working...

 

[bluremi]

did you notice a difference with the new plugs on the bike?

I decided to replace them because I started to notice an increased vibration above 6000RPM and a concomitant decrease in power delivery.

I haven't had a chance to test ride it with the new plugs yet, should do so this weekend and will update the thread...

 

[FinalImpact]

Just for numbers, I replaced my originals at 20k miles. Not because of failure but because I was worried that I was pushing the limits of the plugs to a point that it may fail. Then I replaced them with Iridiums and logged over 50k miles on them. Replaced them for the same reason, could have gotten more miles out of them but the heads were off on the bike so it was a no brainer to replace them at that time.

Nothing personal - but just because it was still running at 20k, that doesn't make it right or sound advice for everyone else.
OEM plugs WEAR FAST! There is NO good reason to leave them there past 12 - 15K mi. Yes, the OEM Spec calls out 8,000 miles and that's bit early and 20K is clearly too late on a waste spark system fitted with carbon electrode side burning plugs. But its your bike and you are free to do as you please. Just don't count on me pushing it off the road if you neglect it! lol

 

[FinalImpact]

...one of them does not look like the others:

View attachment 65077

This is after 12.5k miles. What does the white residue on the #1 spark plug indicate? It's on the bolt rather than on the head, and it's not powdery/rubbing off on my hands.


For posterity, this was easily done following the instructions on How to: Replace your sparkplugs in 20 minutes - Sportbikes.net

Didn't unscrew the radiator or anything. Whole job took a little under 1 hr with a few breaks to stretch my knees and drink my beer.

The weep hole on the right side of the cylinder head is to allow oil and water out so it doesn't short the plugs and cause a misfire (make you walk). It also allows visual should the valve cover gasket fail and leak oil, should there be build up in the plug wells.
More often than not, the water is shot into the weep hole during washing via garden hose or those doing pressure washing which makes the plugs plating oxidize.
FWIW: all four plug wells are connected through a passage just above the spark plugs seat area.

 

[VEGASRIDER]

Nothing personal - but just because it was still running at 20k, that doesn't make it right or sound advice for everyone else.
OEM plugs WEAR FAST! There is NO good reason to leave them there past 12 - 15K mi. Yes, the OEM Spec calls out 8,000 miles and that's bit early and 20K is clearly too late on a waste spark system fitted with carbon electrode side burning plugs. But its your bike and you are free to do as you please. Just don't count on me pushing it off the road if you neglect it! lol

I was just providing some unique numbers, and I'm definitely not giving advice that they should do the same. I'm one of the first to admit, when it comes to maintaining the service interval of the bike, I get an F. But my bike is still running so they are pretty much bullet proof, unless you crash and total it.

 

[bluremi]

Just adding a trip report:

It's subtle but the vibration is definitely better, and it feels like there's more power above 7000RPM.

It is definitely idling more evenly now.

About what I expected from doing the recommended maintenance