[mattysigpi]

I wanted to say thanks to anyone that replied...I really appreciate all the help...as far as the carb jetting, I have no clue what that is, but can assure you I have not changed it....I did do an oil change right away and made sure the tire pressures are ok....I have since wd40'd the chain and it looks great...I still can't figure out this damn backfire problem though...air filter is clean as a whistle too