Bought bike new October 2017 in Florida. Rode to Mississippi for first oil change (500ish miles) then across to New Mexico. Changed oil September 2018 with factory recommended Castrol Power 1 4T 10W40 at that time and again this month October 2019. Factory recommends annual or 10000 mile intervals. Basically bike has had Castrol Motorcycle 10W40 since new. Apparently sheared down to about 10W30 per this report if I read it right. Decided to pay for TBN this time, well just because. I ride year round so may try the 20W50 next time but wonder about cold starts in winter. In any case posting report for future reference if anyone is interested.