What I do with new 4-strokes is fill the crank case to the bottom of the threads with cheapest detergent 30W oil I can find, start it up and let it idle with an occasional 1/2 throttle twist for several minutes.
Then ride it around my test area here which is mostly residential 25MPH, a nice little 'hump' hill and big hill up the mountain, and some stretches to open it up to 50+ MPH if it will do it.
4 or 5 circuits (~1/2 gallon) then drain the initial oil while it is warm and fill it with the same stuff and instruct the customer to change the oil after 2 gallons of gas is run with good quality synthetic oil and just change it once a year or so and you're good.
The MAJOR ISSUE with 4-stroke kits on an MB is what a frigg'n hassle it is to dink with the oil at all.
Just some HS 142F 4-stroke engines on a flat level bike platform tips:
1. Ignore the useless dip stick, fill the oil up until it gets to the threaded barrel just under the bottom thread.
2. Forget the oil drain plug or laying the thing down to drain oil, or some funky funnel thing that doesn't allow you to look into the fill hole for oil level as you fill it.
I have found a big plastic syringe with an 8" or so gas line on the end allows me to do a complete oil change with no mess in about 5 minutes.
Just suck the old oil out and put it another oil container to use as chain oil.
Then stick it in your new oil container and suck it full and fill the engine back up to the bottom of the cap threads.
The type of syringe or line is not important so long as they will connect together, the important thing is you take gravity out of the process to make it much faster, cleaner and easier to do which is why I include that with new 4-stroke builds.