Reading Spark Plug

[02'Cr Rider]

I have a 2006 YZ250 with stock jetting on 91 octane mixed @32:1.See picture on plug color and black ring.I was riding sand wash WOT most of the time @ 1000' elevation.I mainly ride offroad were the trails range from 1500-3500'.My question is should I lean out the main to a 175? Since the black ring can be push down a little more.What do you think?

http://i6.photobucket.com/albums/y212/trailrider121/2006_0924Image0003.jpg

 

[BSWIFT]

Dude, that plug looks great. If your running WOT alot, leave it right there. Better to be a bit rich than lean under those load conditions.

 

[trial_07]

I agree with BSWIFT.

 

[02'Cr Rider]

You think I should lean out the main on slower tight stuff?

 

[Rich Rohrich]

If the plug has that much color on the ceramic with it WOT under a heavy load like sand then it's bound to be too cold a plug for slower stuff. Get the plug heat range correct first. How the main is set for slow speed work doesn't really matter because you'll never use it. ;)

Get the plug heat range correct and get the pilot and needle sorted and you'll be good to go in the slow stuff.

 

[02'Cr Rider]

Update,

Hey Guys,

Check out some pictures of my spark plug and let me know what you think.The bike is trail ridden between sea level and 3000' most of the time.Temp around here is about 68-80 degrees.Bike is all stock with pro circuit spark arrestor.I'm a B intermediate rider,so the bike does get ridden hard.Check out the BR7ES plug,is it too hot of a plug?Jetting was perfect with the BR7ES with no spooge at all.

Current jetting:

178 main
48 pilot @
A.S @ 2 turns out
N3EJ needle @ 2nd pos.
pump gas / mixed 32:1 with Torco GP-7 premix


http://i6.photobucket.com/albums/y212/trailrider121/2006_1106Image0001.jpg

http://i6.photobucket.com/albums/y212/trailrider121/2006_1106Image0002.jpg

 

[trial_07]

I am no expert, but it looks a bit too pale.

 

[Rich Rohrich]

.Check out the BR7ES plug,is it too hot of a plug?Jetting was perfect with the BR7ES with no spooge at all.

It looks much better than the first one you posted.

The plug temp looks right on this one and the carbon ring at the base looks correct if the plug chop was done at WOT.

 

[02'Cr Rider]

Thanks Rich....

The plug chop was done a WOT.The plug has no black carbon on the shell flat surface,but it does have a blueish color on the shell.Does that mean its got hot? I want to run the BR7ES,but I dont want to melt a piston either.