so i have been working on my 300ex, it jumped a tooth on cam but set it back to normal now, before i messed with the carb so i am adjusting the pilot screw. when ever i punch the gas, the quad dies out a litle and has a delayed reation. what do you think i should do with the pilot jet? or is it something else. and theres a bit of an air leak in the exhaust so it cuases the back firing.