plug color?

[crash_77]

could someone tell me if my plug looks "normal" rich nor lean. i raised the needle to the richest setting (per yoshi's recommendation). the only mod to my 05 predator 500 is a full yoshi rs3 exhaust. reason for moving needle was the exhaust was a nice brown/bronzed color after running with new exhaust except where the head pipe connects to the engine (it was bluish in color. called yoshi and they told me i was too lean. i put a new plug in after changing needle position and have ran about a tank full of fuel through it.
http://i76.photobucket.com/albums/j33/shane1230/spark%20plug/IMG_0019.jpg

http://i76.photobucket.com/albums/j33/shane1230/spark%20plug/IMG_0020.jpg

[calds650]

looks just a tad lean

[polaris bob]

Actually, it looks just as touch rich to me, but I would leave it alone for now.

If that is the plug from just a day of play riding or out on the track and not a plug chop you should be just fine. I would leave it like it is and see how it looks after a few more hours of riding.

Or go out and do a full throttle plug chop and see if it changes any, that would be a better way to check your top end jetting rather than just pulling the plug after a day of trail riding.

[smokinwrench]

I say its a bit lean. I would go up one main jet and see how it looks.

[crash_77]

I thought it looked lean myself. but then again i didnt examine the old plug, before changing the needle. I just richend the needle because the pipe was bluish in color at the head, and thats what yoshi recommended.


PolarisBob- yes the plug pic is from a day of riding about 3/4 throttle at my buddies house.

[polaris bob]

Plug is fine then. You guys have to remember that a 4 stroke does not color a plug like a two stroke does. You have to look at more than the color of just the tip of the insulator.

You need to look at the tip of the center electrode, the whole insulator, especially the inner part where it meets the shell ( which we can't see in this pic!), you need to look at the end of the threads, and the ground strap.

What I see in that pic is some carbon build up on the threads, and a lot of color on the insulator, at least the part I can see, the center electrode looks to be running at the right temp, as is the ground strap, which is allowing the plug to burn hot enough to burn off the carbon build up.

In that pic there are no signs of deto on the center electrode, and the very edge of the tip looks nice and sharp still, which is another sign that the timing is correct for that motor and the way it is being run.

Add that all up and that's where I see that it seems to be running just a tad rich but for the average trail rider it would be fine.

But keep in mind that this is just the opinion of one guy looking at a pic of a plug, on a computer screen. LOL

There are some good pics on this site as to what a good running plug should look like.

Look here for the story and pics.

http://www.atvriders.com/articles/sparkplug.html

[crash_77]

polarisbob - thanks for the info and great link

[predle]

it looks rich, when mines tuned good its very light grey to tan as long as its not pure white or spotted its ok

[predle]

if it was for performance id go down a slight bit then make sure its not popping or getting hot course it safer going rich

[crash_77]

thanks for the replies and input. i have since moved the needle one notch from the bottom posistion (it was on the botom most notch). it looks much better. it looks more of a tan/cardboard color now.