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Ripped apart and put back together the sm tonight to do a plug check. Jd jet kit blue #4 25 pilot 160 main. Rs2 corked. What do you guys think about the plug color?ImageUploadedByThumper Talk1401845675.757840.jpg

How lean would it be if I pulled the quiet core out of the pipe?

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Ripped apart and put back together the sm tonight to do a plug check. Jd jet kit blue #4 25 pilot 160 main. Rs2 corked. What do you guys think about the plug color?attachicon.gifImageUploadedByThumper Talk1401845675.757840.jpg

How lean would it be if I pulled the quiet core out of the pipe?

Looks lean already,  pulling quiet core would make it leaner.

Edited by billdirt1
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really hard to tell from the pic, and don't know if your trying to jet of a new plug or old, or what type of riding you were doing before you pulled it?    from what I see it looks ok, but it's hard to tell.   I'm not looking at the color or the porcelean at all. I'm looking at the heat signature on the ground strap, where you can see the change in heat.  Your pic looks likes it's at the green arrow which would be fine. You'll have to look at it closer as it's hard to tell from the pic.,

 

 

 

 

plug.jpg

 

Edited by highmarker

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really hard to tell from the pic, and don't know if your trying to jet of a new plug or old, or what type of riding you were doing before you pulled it? from what I see it looks ok, but it's hard to tell. I'm not looking at the color or the porcelean at all. I'm looking at the heat signature on the ground strap, where you can see the change in heat. Your pic looks likes it's at the green arrow which would be fine. You'll have to look at it closer as it's hard to tell from the pic.,

attachicon.gifplug.jpg

after I did the jet kit and followed all the instructions I put on about 140 miles of mostly mid throttle. This is the original plug in the bike and the bike only has 1000 miles on it. I'm stumped as to why it's running lean when I even called jd and set up everything as they recommend. What would you suggest I do to get a nice tan across the band or maybe even slightly black

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really hard to tell from the pic, and don't know if your trying to jet of a new plug or old, or what type of riding you were doing before you pulled it? from what I see it looks ok, but it's hard to tell. I'm not looking at the color or the porcelean at all. I'm looking at the heat signature on the ground strap, where you can see the change in heat. Your pic looks likes it's at the green arrow which would be fine. You'll have to look at it closer as it's hard to tell from the pic.,

attachicon.gifplug.jpg

I looked at the original pic which is better and can confirm that your right on the heat change. Just not sure what the heat change is necessarily. I have always went by color

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If you followed jd's instructions your good. Hard to jet off color only  with todays fuel.  If the plug reflects 140 miles of normal riding your likely seeing the needle in the 0 to 1/4 throttle range.  The jd blue at 4 should be too lean there.  Whats the inside end of the pipe look like? does it surge at light throttle?  is there any other sign of lean other just looking at the plug color?

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If you followed jd's instructions your good. Hard to jet off color only with todays fuel. If the plug reflects 140 miles of normal riding your likely seeing the needle in the 0 to 1/4 throttle range. The jd blue at 4 should be too lean there. Whats the inside end of the pipe look like? does it surge at light throttle? is there any other sign of lean other just looking at the plug color?

what would I be looking for on the inside of the pipe? But at any throttle position the bike runs excellent. I was told that the header would turn "funny colors" if I was lean too. But it's just turned gold for lack of better words.

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If you followed jd's instructions your good. Hard to jet off color only with todays fuel. If the plug reflects 140 miles of normal riding your likely seeing the needle in the 0 to 1/4 throttle range. The jd blue at 4 should be too lean there. Whats the inside end of the pipe look like? does it surge at light throttle? is there any other sign of lean other just looking at the plug color?

I can't complete my thoughts today....I only run premium fuel in my bike also if that makes any difference to you. No ethanol in it at my gas station

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what would I be looking for on the inside of the pipe? But at any throttle position the bike runs excellent. I was told that the header would turn "funny colors" if I was lean too. But it's just turned gold for lack of better words.

nooo it will not change color if your jetting is wrong. usually thin walled headers will change color when getting hot

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if your bike feels good when riding it, keep riding it. you cant judge everything on your jetting by the color of your plug. although the color of your plug is a good interpretation of lean or rich conditions i would keep running it if the plug fouls then you have problems.... i see the sweet spot on a extended fuel screw to be around 2.5 turns..

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The plug looks normal to me...It's extremely difficult to accurately read a spark plug nowadays with the chemical mix of modern fuels....

If the bike is running ok, rest easy , put your feet up and have a beer or 2.... ;)

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The plug looks normal to me...It's extremely difficult to accurately read a spark plug nowadays with the chemical mix of modern fuels....

If the bike is running ok, rest easy , put your feet up and have a beer or 2.... ;)

I shall have a drink or two now haha. I may pull the quiet core out too because apparently you lose quite a bit of power with it in there so I'll give another plug check after 100 miles with that out to

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I looked at the original pic which is better and can confirm that your right on the heat change. Just not sure what the heat change is necessarily. I have always went by color

Throw a cup or two of leaded race fuel in your tank and watch that plug color right up.

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I shall have a drink or two now haha. I may pull the quiet core out too because apparently you lose quite a bit of power with it in there so I'll give another plug check after 100 miles with that out to

 

Honestly mate your wasting your time checking the spark plug colour.

Even if it's a tad lean (which I extremely doubt with a160 main jet and blue needle , clip 4),..... a four stroke has to be seriously lean to cause any issues....

Classic extreme lean symptoms include severe high rpm misfire and bad surging at mid throttle settings....

If it's running well and pulls cleanly .....rest easy and keep crack'in beers..... :cheers:

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Honestly mate your wasting your time checking the spark plug colour.

Even if it's a tad lean (which I extremely doubt with a160 main jet and blue needle , clip 4),..... a four stroke has to be seriously lean to cause any issues....

Classic extreme lean symptoms include severe high rpm misfire and bad surging at mid throttle settings....

If it's running well and pulls cleanly .....rest easy and keep crack'in beers..... :cheers:

Some good point(s) Craigo, it's just so hard for me to let go of my 2-stroke roots.  :facepalm:

Edited by billdirt1
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