I just bought an '05 Kawasaki ZX-12R. At the 600 mile service I asked the technician at the dealership what oil he recommended. He recommended the standard (conventional) Honda oil which is what they put in everything they service unless you want something else. He said there would be no benefit using a synthetic oil. Is that true? It calls for 10w-40. I don't mind spending extra money on a premium synthetic oil if it is better for the engine. I don't race this bike but I do ride aggressively, taking it to redline fairly often. What do you recommend?