You could have a little rust or crud in the clutch drum causing it to drag if it is idleing at the right speed. If it's idleing a little faster there might be a little crud in the low speed circut in the carb. If it tries to die when you pull the trigger after warm up it would be a dirty carb. Running it out of fuel does not get all the gas out of the carb, use Stabil. If it's just rust in the clutch drum that will clear its self up. You could try a little Sea Foam in the gas if it's a dirty carb Steve

What can happen beside crud build up is small string or wood threads from sawing fiberous wood like palm will get wrapped up in the clutch bearing. Either cause you need to remove the bar and chain and then pop off the "E" and ring and washer retaining the the clutch drum. Pull up on the drum removing from clutch assy. Take the bearing out, clean it and lube with a lite grease or bar & chain oil. Cup your hand around "E" ring when slipping it out as they tend to like to go flying and get lost.

When re-installing the drum, obseve a small notch in the rim of the drum and by looking down the side of the clutch shoes [use flashlite if needed] find a small rod coming from under shoes and sticking out just a quarter inch or so. The notch in the drum has to drop over that rod for the drum to sit down all the way and engage the oiler drive.

If you encounter any running problem, look at the fuel line,
especially the rubber between the tank and carb, the part exposed to the air, it generally develope many cracks.
If you have never changed it, you should at least look at
it. If you change it out before the cracks start leaking, you may get by without going into the carb. If you take
a peek at the area under the air filter and see moisture,
then it is leaking.

Fish