My boy's Sportsman 90 starts and idles fine but when he gives it gas to get moving, it seems to flood out. It's a 2-cycle w/oil injection. I'm adequate when it comes to turning wrenches but by no means up to the level of your typical mechanic. I have replaced the spark plug and cleaned the air filter but haven't done anything with regards to the set screws on the carburetor. Any advice would be greatly appreciated.