Hi Dale, welcome.
Rotella T6 5W40 is rated "JASO MA/ MA2" which is for motorcycles, if that is what you are asking. To me this makes it gas (petrol) engine certified even though it’s a HDEO Diesel engine oil with API CK-4 and ACEA E9 ratings. What use to be called a mixed fleet HDEO.
Castrol Power 1 4T motorcycle oil in 10W/40 Amazon had a great sale on the Castrol Power 1 4T a couple months ago and I got a case. They appear to have removed the Power Racing RS oil from the U.S. Market and was curious how this oil compared, or if it was the same and just given a different...
The Rotella T6 Multi-Vehicle 5W30 is API CK-4 & SN rated plus ACEA E6. A VOA here shows a lower 872 ppm zinc
Since I got a bunch of free oil from Shell to try, I felt it was only right to have this done. A prior post puts TBN at 11.
So Regular T6 5W40 for diesels trucks and gas motorcycles. While Multi-Vehicle T6 for diesel trucks and gas cars. That is the general rule, but you may require a particular OEM spec, in which case best to read the other approvals to see it meets that.