I've used nothing but the Shell Rotella T Full Synthetic since I dumped the break-in oil at 500 miles. Somewhere along the way, Shell added theT6 designation. I researched it al at the time, and was satisfied that the change was an improvement, and therefore I keep using it.
I send in a sample at every oil change to Blackstone Labs. It's $20.00, but piece of mind. The viscosity may be lower than recommended, but my oil reports have all been very reassuring. My latest was at 73K, and showed nothing remarkable. I change at about 4K mile intervals, sometimes sooner by a bit, rarely later. My 2004 Owner's Manual showed to, before they later went to 6K recommended intervals.
I really liked what I read about Rotela on the Shell Rotela forum...there is a forum there for motorcycles. Bottom line is, it works, and it's reasonably priced.
