You'll have to adjust the hi-speed mixture needle valve. It will take a special screwdriver you can get cheap on ebay and other places, but Ryobi won't sell you one. That's what I finally did on my Ryobi because it wouldn't start without putting gas in the air intake, then it wouldn't run at high speed. I need the high speed because I mainly use the blower attachment. Find the two screws on the carb and see if they don't each have a notch in the rim. You need a hollow-shaft driver with an internal pin to fit those needles. Get it running and fully warmed up then slowly open the RH needle (I think its the RH for high speed- you'll find out if its the other one) to enrich the mixture - if it runs stronger, fine, that's where you needed to go. If not, go the other way because it is too rich. Now let it idle, and adjust the lo-speed needle for the best idle. Keep the driver handy. I find I use it almost every time I start the thing. If you have trouble starting the cold engine after the adjustments, open the lo-speed needle about 1/4 turn and use more primer.