Much like the great oil debate, the not-so-great chain lube debate, etc. there is no "straight answer," just case studies and anecdotes.
If you like conspiracies, we might imagine there is a secret government lab at Groom Lake where they have row upon row of ZX-6R engines and bottles of oil. All the engines are run under identical load conditions until they blow up. Then they’re disassembled, and the parts examined for oil film thickness and other parameters. In the end, they’ve definitively established which oil is "better" than the others. Sadly, these results will be quashed by the big oil companies (Big Conspiracy no. 2). And the phone company killed Kennedy.
Keeping that in mind, here’s another interesting anecdote: my dealer sold me a slightly-used ZX-6R he used for his personal amusement before deciding it was “too slow.” Whatever. Anyway, when I asked about break-in, he rolled his eyes and said this: “look, you’ve been riding a long time. Think back to when you were 19. How many young guys will hold the bike under 4K (whatever) RPM the first 600 miles? It won’t happen. Also, these bikes are run in club and national races all the time right off the floor. They spend the beginning of their lives at race practices on Saturday, racing on Sunday. Damn few if any blow up due to “incorrect break-in” as a result, given today’s modern metallurgy, casting processes, CAD/CAM tight-tolerances, etc. I broke this bike in on a dyno <pointing to the back of his shop>, then ran it a couple WMRRA <race club> practice days. The remaining hundred miles are around here, stop-and-go traffic on the street!”
The bike now just turned over 600 miles I changed the oil to <I’m not telling>, since it looked rather skunky in the sight window right after I took delivery. It’s broken in, makes astounding power, and doesn’t appear to have the least engine or other problem. When I’m done with a track day this Friday, I’ll change the oil and filter again plus perform other 600-mile service steps myself. I’m handy with tools and have a garage. No more thought shall I give this matter.
Hope that helps.
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-=DRB=-
Mill Creek, WA U.S.A.
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