I'm having a heck of a time trying to find an appropriate motorcycle oil for my bike, which is calling for a 15w-40.
The only legit option I can really find with a claimed (but not actually certified) JASO MA rating is Rotella T4.
I've heard it didn't shift too well in my Kymco Spade, so I'm looking for an alternate. I came to discover that the JASO MA rating is pretty much just a lack of energy conserving, friction modifiers. And I also discovered that any Universal Diesel Oil with a trailing 40w or 50w viscosity rating supposedly lacks these friction modifiers.
So basically, I found two dino alternates to the Rotella for my break-in.... Some old stock "NAPA Performance" 15w-40 (rebadged Valvoline) that actually comes in 1 quart bottles... Or Mobil Delvac Super 1300, which I can only find in the larger jugs.
I ended up buying the old stock NAPA oil because (1) I only need 1 quart for my break-in, and (2) the specs for that bottle looked pretty much ideal -- No moly and about half the calcium of the Rotella with more magnesium and maybe more zinc and phosphorus (can't remember for sure, but they're at least similar here).
Does anybody actually think this is a terrible idea, considering this rebadged Valvoline oil doesn't claim to meet JASO MA standards, like Shell does?
And what non-Shell options are there for Synthetic 15w-40 oils that won't cause my clutch to slip?? I'm asking for non-Shell options, because Rotella T6 is not a 15w-40, and even Shell recognizes that their T5 synthetic blend isn't appropriate for motorcycles..... not because it has friction modifiers, but because it's TOO THIN... even tho it's claimed to be a 15w-40, it's really not. (See here for that: http://pqiamerica.com/HDEO_Sample_Summary_Dec_2016.html )
So is there anything synthetic in this viscosity that doesn't come from Shell that would be appropriate for a 5 speed mini motorcycle? I'm almost tempted to just go with a 15w-50 or even a 20w-50.... but I'd certainly prefer not to.