[BlackBike]

It appears you struck oil. And crude at that now take that amount, replace, then be ready to check the site glass/dipsticks oil level. Will need to check and top off and also check it as the bike is on the level and not on the stand. That said the best thing for it, clean oil. You'll even feel a difference in the shifting.

Also, rock it over so it all comes out.

And also good to heat the oil before draining (run it around the block). Hot oil flows better than cold oil (Watch out, it burns skin too).