motor lean condition

some of you know my bike blew out a plug. i did notice when i took the motor out of hte frame that hte 2,3 clyniders are white inside. my header 3 pipes out of 4 are white. my old plugs were white. to me this sounds like a jetting issue. i called the dealer and told them this they told me it was my coil. if it was the coil wouldnt it not spark and just load up the cylinder with fuel? im taking hte motor back to them today. i just want to have this clairfied before i go bitching about my motor. i shouldnt have to eat this because of tuning.