I currently have Repsol 4T racing syntheric in my bike, and I'm at the end of my first 5K with my oil and filter. I plan to change oil and leave the filter on for the second 5K. I am switching to Mobile 1, either now or after the next change, and I have about a liter of Repsol in the bottle on my shelf. Question, should I go get enough Repsol for the oil change, or is it OK to mix the Repsol in the filter with the Mobile 1 I'm using for the oil change?