reading spark plugs properly

[camoweasel]

I've been reading many sites on the internet, and talked with quite a few 4stroke guys, and it seems like everyone's way of reading spark plugs varies. For instance, Trinity Racing states that base ring is the proper way to determine a plug's air/fuel mixture. They claim with today's fuels, it's impossible to to determine jetting by the color of the porcelin. Other's like the service guy at a local dealer claim that the porcelin is the only way to read a plug and has been since the beginning of time.
The reason I post this is because, after having my head ported and using my 400ex carb, I can not make the porcelin change colors. I'm up to a 180 main jet, and when I do WOT plug chops, the porcelin is white, and the electrode is grey, BUT the base ring does have black carbon around it. And when the porcelin does stat to turn brown, only one side of the porcelin turns brown and the other stays white. I would love to have a brown plug. Honestly though, I have no problems anywhere in the power band, and it pulles very hard through all the gears. Ican't believe the power difference after my top end rebuild.
Basically, I want to know, what part of the plug is the proper way to determine one's jetting?? I really want to know, because as the weather warms up, my engine does tend to run hot as to if any oil leaking from my head cover would actually start smoking.

[camoweasel]

Any experienced 4stroke techs out there?

[camoweasel]

One more time...

[harryredtrike]

the porcelain will not help you.go to world class help section and you will find a plug chop thread.you have to pull the plug and look at the electrode.black and dry means too rich.black and wet your burning oil,white your too lean on your fuel,a carmel color is what you want.

[1984 honda 200s]

+1 ^^ Harryredtrike, shoot for caramel colour!