2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 88Get this manual
CHECKING THE ENGINE OIL LEVEL 1 b
3Check: engine oil level Oil level should be between the minimum level mark and the maximum level mark bLow oil level Add oil to the proper levelNOTE: Wait few minutes until the oil settles before checking the oil level Do not screw the dipstick in when checking the oil levela