This spark plug look too white (learn) for me. Brown ir the gold spot.
Had this spark plug for how long? If you rode few hours with this one, you need bigger jets.
To retard the timming, you need to rotate de plate same direction flywheel rotates.
Flywheel nut is veery tight. You will need a impact wrench. Mark nut and axle with a chisel. So, you will know how much you should tighten on reasembly to keep same tension.
Lack of torque in this nut can cause sheared key
In fact it is not the cap that is green. The rubber under the cap that is green when mineral oil is used. (Mostly)
You can double check with a drop in water:
1 dot oil mix well with water and turn white.
2 mineral oil floats
Seems ok to me.
If it is normal, sound should keep average the same as time goes
If there a problem, it probably will get worst and worst.
So, give bike a good ride, have fun and hope everything will be fine
Mark the nut and axle relative position first.
Than remove nut with a impact gun
Change seal
Reinstall nut with impact gun untill marks realign again.
This way proper tigtening is garanted
