Throttle Cable Adjustment
It should be easy.
1) Loosen the locknuts at the upper end of the throttle cables, and screw both throttle cable adjusting nuts in completely so as to give the throttle grip plenty of play. As you sit on the bike, the cable closest to you is the decelerator cable.
2) Turn out the adjustment nut until there is no play when the throttle grip is completely closed and tighten the locknut.
3) Turn the accelerator cable adjusting nut until 2 to 3 mm of throttle grip play is obtained and tighten the locknut.
Those are directions (more or less) straight from the owner's manual. This was like the first thing I had to do since the bike came with about an inch of throttle play!