My battery is weak, would this cause my problem? Sometimes you have to crank it with the pull start.

 

The battery being weak wont matter. Sounds like you need to adjust the air screw when it is hot or maybe it needs to be re-jetted. Most likely it is your airscrew. Turn it 1/2 turn counter clockwise at a time when it is hot and see how it runs. The airscrew should be at least 1 to 1 1/2 turns out. If it is not out enough then it will hesitate.

 

Is there an easier way to get to the air screw, I can't get to it without removing the carb.Text

 

Your saying that it's hard to crank the engine over when it's hot? Yes your battery would be weak if that was your problem. Polaris starters are junk and wear out, you might need new brushes in the starter.