A friend of mine has bought a 2014 ktm 250sx. He's just getting back into riding dirt and I've been taking him trail riding with me. I don't think he's riding the bike very hard or clearing it out in the tight single track which is understandable. He fouled 3 plugs yesterday. I took the bike for a spin and it sounds like the pilot jet is too lean when cruising, the bike pulls like a mother up top and rides normal aside from the knock at partial throttle. I pulled the plug after taking it for a spin on a fire road and it was nicely browned. With him fouling plugs in the tighter trails what should be adjusted? I'm going to go up one pilot jet to remove the knocking at low throttle inputs but aside from pulling his skirt out of the chain or carrying a case of plugs what should I look at?