I use this method see if you agree bike is cold i drain the oil and filter change but fill the oil filter with a little oil
this way all the dirty oil comes out or if its cold you may want to let it sit in the sun.
i use 2 quarts 20/50 1 quart 10/40 in summer 20/50 is kawasaki oil non synthetic and gn4 honda 10/40
I believe to change the oil every 2000 miles and change the filter as well and synthectic just is no good for my bike makes the clutch slip I am sure it is bad for all but who am I to say .
wet clutch bikes should stay with non synthetic unless you do not mind paying for a clutch
I know the dealer says its ok to use synthetic but will they pay for your clutch lol
be safe change your oil freq and every bike is different on levels put in 2.5 quarts and a lttle in filter start it up run for 2 minutes shut off wait 10 minutes then level bike with wood or whatever you got
then check level after it sat and screw in the stick if you have a window you should see it 3/4 full in glass
do not put mystery oil in oil gas is ok not in oil do not use car oil unless it is an emergency
i think no additives in oil is best 10/40 in cool weather 10 /30 in winter if your crazy enough to drive it or start it up at times
but lucas in gas is ok just a small amount mystery oil is good an ounce to a full tank and marine stable if it going to sit plus remember to keep the tank full so condensation does not get in there.
if you use mystery oil you will see better gas mileage easy starts and cooler running bike