2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 229Get this manual
CARBURETOR EBS00150
ASSEMBLING THE CARBURETOR CAUTION:
Before reassembling, wash all of the parts in clean petroleum based solvent1Install: pilot screw NOTE: Before assembling the carburetor, make sure to turn out the pilot screw the same number of times, as noted before disassembly, from the seated position to the set position_