I went for a ride on my 2005 KX 250 today, and did a plug chop at the end of my ride. I pulled the plug at home when the engine was cool. Does this plug look too lean?
I was using pump premium 91 octane fuel with no ethanol, mixed at 40:1 with Motul 800. I am in northwest Wyoming at about 5,200 feet above sea level. The ambient temp was 40 degrees F with very low humidity. This plug is an NGK B8ES. It looks OK to me, and should be just a touch rich this summer when its 80 degrees out.
What are your opinions?
Thanks!