2014 F700GS I went to order 15W50 castrol oil from Amazon a few days ago as im going to be doing my first oil change on this bike for the 9k (other service has all be done at dealer). Service manual says castrol 15w50. I received it and it's 10W50. Looks like a made a mistake when ordering. After researching more I can't even find a castrol 15W50. Ok so can I use the 10W50 or should I return it? Do I order Mobil1 15W50 or goto the dealership and pay extra for their flavor of it? And yes this is an oil thread. Don't get your panties in a knot.