2017 KTM 300 XC-W SIX DAYS....JETTING?

A smaller pilot and adjust the air screw to get the idle back.... IF its actually fat.

For me the first step in Jetting any two stroke is making sure the piston to head clearance is in the ball park. That has a HUGE effect on how they respond.

 

What he said. Proper squish will make a huge difference. Not familiar with KTM, but I know the Gas Gas measurements from the factory are huge (2mm+) which makes jetting a pain in the ass.