This is in my Yamaha DT250 so probably in the wrong thread, my apology.
Johnson Valley about 3000 elv. Coming back from the last ride on a dirt road, 1/4-1/2 throttle. The plug was black, not oily, sooty.
Situation is it runs rich with clip on 2nd position (from top) after installing Boysen Reeds, which they said is normal and leaning mixture may bey required. So was thinking going one size leaner needle jet to get the clip closer to the middle, so to have leeway riding in higher elevations. I live at sea level.
The plug didnt foul, but at times after starting cold sometimes it will foul. Once engine hot, no fouling.
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