I have always used the factory recommended oil at the factory recommended intervals. I haven't had any issues with any motorcycle due to this practice. I am currently jonesing to change the oil in my Super Duke, but it says 9300 miles and the oil still looks clean at 7k so I am riding it out. Killing me, but I see no practical use to doing it early unless there is an issue/leak/failure sort of thing. I do ensure that whatever bike I am changing oil on gets motorcycle specific oil in the tranny so the wet clutch isn't "challenged" due to lack of grip. But, like tires and brake pads, what works for me may not work for you. Of course, the dang Motorex is some pricey stuff but I use it anyway. I also use their coolant, brake fluid (DOT 5.1) and their Hydraulic clutch fluid (Mineral oil as applicable). YMMV