I have a 2009 KLX250SF. I live at about 350ft ASL. Snorkel off, Big Gun Evo R exhaust slip-on.I have a 17.5 pilot jet, 130 main, and the stock needle jet and jet needle. Jet needle is all the way to clip 5(lowest clip.) Went for a run today it was about 65 degrees and it stalled along the way. Started back up after about 10 minutes. Took off the tank and checked the sparkplug. White/Grey. Couple dark spots that looked like speckles. I checked the rubber boots and they look to be tight. Am I missing something? I forgot to add that the carb isn't a CVK34 anymore, it is a TM-36-68 A/P. The main jet came stock at 130, but the idle would drop very slowly when I gave it throttle and my friend owns some Harley's and had a left over 17.5 Mikuni pilot jet that he let me use, it was a 12.5. I thought it was lean because when I went for a ride it felt like it was hauling ass. Lifted the front wheel off the ground a from first to second gear.