It must be winter again.
FWIW, Rotella T6 is an approved moto oil, as it states on the bottle that it meets the JASO MA spec. As of two months ago, Chevron, Mobil, and Kendal diesel oils in non syn may or may not meet that spec, the bottle doesn't say. My ASSumption would be that they do not, but it may be that they just haven't seen the need to test for it or bother getting it approved. Rotella has the spec listed, so I use it.
The manual does call for an oil that meets the JASO MA spec, among others.
Happy oil thread. Yeehaw!!!!!!!!