I normally do not participate in oil threads but since we selfishly and without regard hijacked it, I feel obligated to provide an answer.
Firstly I want to address the moronic statement that normally goes like this in oil threads: “I changed my oil with brand X and it works great for me”. So you thought there might have been a chance that it would not work and your engine would blow up??? To the contrary, one could buy oil at the local supermarket for 69 cents a quart and only change it every 7,000 miles, twice the recommended service interval for a Hayabusa and the engine would still last 100,000 miles without any problems. There will probably be more wear inside the engine versus one that was serviced with a high quality oil at proper intervals but even the cheapest oil sold would not damage a stock engine.
For modified engines, it is a different story. Normally aspirated engines typically have higher redlines and more extreme cam profiles. Film strength becomes important here and I would suggest looking at tests from independent labs. Just be careful with how recent those tests are since oils are often reformulated even though they are sold in exactly the same bottles and under the same names. What drives that is EPA requirements and the big oil companies also have an army of chemists and engineers with fancy PhD degrees that do nothing but try to improve the performance of their products.
Turbo motors have different requirements. Bring your Busa to a certain individual in Canada and you will now have 600+ RWHP versus 155 stock for less than one bet at the black jack table in one of the high roller rooms here in Vegas. With that amount of power, the loads on main and rod bearings are extreme, so diesel oils are often preferred in those motors since they are designed for that application. Oil for turbo motors must also be resilient of very high temperatures.
You mentioned “Less than Zero” which refers to the oils viscosity. The only reason to use that type of oil is to put up a number at the drag strip. Brock’s business model is to put a 135 pound jockey on a sport bike with stock engine internals and lay down an ET at the quarter mile that is absolutely impossible to achieve for you and I and 99.99 % of all sport bike owners. I would not under any circumstances use that type of oil.
Lastly, mineral or synthetic? There is no doubt that synthetics performs better in extreme warm and cold climates. They also typically have higher film strength than mineral oils which is important with lumpy camshafts. I know some guys that run seven seconds Pro Street type bikes at the strip and use mineral oil. But they change oil after each event and will at the most have two miles on it. Also, the crankshaft only rotates approximately 1,100 revolutions in a quarter mile pass and the camshafts half that. So the load is very short in duration compared to say a similar motor at Bonneville.
To summarize, mineral or synthetic is fine for stock motor applications. I would personally not use anything but synthetics for modified engines. Change it at least as often as recommended by the manufacturer for stock engines, more often if modified. Ask your engine builder what he recommends. I would use motorcycle specific oils for motorcycle engines (unless turbo). For what it is worth, I use Mobil 1 4T for my stock Busa and DRZ 400. I use Motul for my ZX-10 that has a flashed ECU with a 500 RPM higher redline than stock. My high performance NA Busa also get Motul. Always use OEM oil filters. That is based on my experience when working professionally as an engine builder before I started my military career and from threads on different forums where the owner felt the need to be creative and either use some fancy setup or a cheap auto part type filter that caused oil starvation and ruined engines.
