I put this together to keep out in my shop. All info is from the listed Manual.
KYMCO 450I Cyclepedia Service Manual
Oil Drain Plug – 19mm, Oil strainer screen pg 108
Oil 5W-30 Motorcycle / ATV Specific 2.4L, 81.15 oz, 2.54 Quarts w/Filter
Oil Filter – Volar OF-026
Front Differential - 80-90 WT 250CC 8.45 OZ Pg 115
Rear Differential - 80-90 WT 230CC 7.8 OZ Pg115
Lube/Grease Pg 121
Cooling 2.65 QT Engine and Radiator
Idle 1300RPM +/- 100 Throttle Adj Pg 134
Spark Plug - NGK CR6E 0.8-0.9 mm .031-.035 8.7 ft Lbs
Front Tire 10 lbs
Rear Tire 14lbs
Toe in Adjustment Pg 130
Air Intake Filter Pg 74
Air Cleaner Element Wet Type Pg 54
Torque Specs Pg 40
Spark Arrestor Torque 48 Inch Lbs.