Originally Posted by metroplex
Amsoil has 15W-50 synthetic motorcycle oil that meets JASO MA/MA2 for Ducati and other metric bikes. In the past I've run M1 V-Twin 20W-50, Rotella T6 5W-40, as well as Castrol 10W-50. The Castrol 10W-50 is a good balance and allows my wet clutches to grip properly during WOT shifts. The Rotella T6 claimed to meet JASO MA/MA2, but at WOT the clutches would slip trying to grip after each ship. The M1 V-Twin worked fine, but just felt harder to start and was noticeably thicker. I bought some of the Amsoil 15W-50 and plan to run it along with one of their EaM138 oil filter. Their EaM line of oil filters are the highest quality with a 25k? service interval instead of 15k.
I couldn't find the Amsoil product on the JASO filing list online, nor could I find it on the API list (although it says it is API SM).