im having trouble figuring out the correct way to stiffen the shock i know its simple but when i try and turn the screw it wont move.

 

PB blaster/WD40?

 

Before you go nuts, make sure that the screw is not fully tightened (clockwise) in other words does it turn anti-clockwise. You also have the collar on the bottom of the shock adjustment to stiffen the springs (preload). Also the adjustment for rebound damping.

 

You do have the bike up on a stand, right?