KYMCO MXU 500i 2018 Service Information page 105

2.Periodic Maintenance
Install the filler cap and tighten it securely with a 17 mm socket.
Item
Rear drive gear oil filler cap
Q'ty Thread dia. (mm)
1 30
2-48
MXU 500i/700i
Torque
Kgf-m (N-m, ft-lb)
1.5 (15, 11)