Multi-colored plug question

Today I removed my spark plug just to see how it looked with regards to color. The bike is an '07 YZ250 smoker and the plug is an NGK BR8ES. A while back I re-jetted the bike with a #170 main, #45 pilot, and swapped out the needle for the JD Jet Kit red needle with the clip position set to the 2nd from top. The bike has been running great since then, with no spooge or fouling issues at all. It started today on the first kick after having been sitting for a few weeks. My question pertains to the appearance of the plug. The color is tan on one side, and a light brown or bronze color on the other side. When a plug is running multi-colored like this, what does that mean? Is one circuit still too rich? My pre-mix is a 40:1 ratio of 93 octane pump gas with Amsoil Interceptor. I have included a couple of pictures that will hopefully describe the situation a little better for you.

Thanks in advance for an explanation of this plug color.

Ron M.

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With today's pump fuel, reading a plug is nigh impossible, however, you plug looks excellent.

With today's pump fuel, reading a plug is nigh impossible, however, you plug looks excellent.

Thanks for the information William1. I appreciate your response.

Ron M.

i have a 07 cr125 [that has SUPER crap jetting] and my plug is more of a dark brown but looks like its fine and it usually fouls within an hour and a half of high revving riding at 40'1 its real weir but im gettin a yz250 smoker as well i hear there a great 2-stroke maybe 07 or 08 model and ur plug looks good its burning the oil off fine from wat i can see keep riding 2-strokes for life

i have a 07 cr125 [that has SUPER crap jetting] and my plug is more of a dark brown but looks like its fine and it usually fouls within an hour and a half of high revving riding at 40'1 its real weir but im gettin a yz250 smoker as well i hear there a great 2-stroke maybe 07 or 08 model and ur plug looks good its burning the oil off fine from wat i can see keep riding 2-strokes for life

DEFINITELY get the YZ250 smoker. You are going to LOVE that bike! I have a 2007 YZ250 and it's the most fun bike I have ridden to date.

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