Hello,
Slydog75,
Change the 75-90wt synthetic gear oil. Drain plug on bottom of gear box. and side fill plug. With bike up right. I always
flush the old oil out with new. Replace drain plug - torque to 25nm. (Drain plug with magnet on it- wipe off)
fill until oil runs out fill plug, replace fill plug torque to same as above.
Not necessary. I repeat process one week later. I usually change at every oil change.
oil is cheap……