I have an 05 blaster 200 it starts but only with throttle full. If you let off it dies, but it also doesn't rev up when throttle is held it just barely reaches a normal idle rpms and anything but full throttle it shuts off the carb seems to be clean and gas is fresh I mixed 4 ounces of oil into a gallon of gas. I put in a new spark plug also and just can't figure it out please help!!!