Nvsteve I'm not familiar with mobil 1 15-50 for $6, only the VTwin 20-50 in full syth....is the mobil 1 your describing a syth or reg dino?

 

And I would be all over the T6 if it came in 20-50, the T6 is a 5-40 which in a Twin cam is thinner than I prefferdue to how warm they run?

 

Full synthetic. When Walmart discontinued carrying it they were selling it for
$22 for a 5qt. jug. Heard they were going to start stocking it again.

 

Humm so this is an automotive Mobil 1 full syth in that weight that a lot of guys are using in their bikes then.....

 

JASO ?? Japanese Automotive Standards Organization

So your Harley is made in Japan, is it?

 

Yes. The Mobil site actually says it is fine but says not to use it in the primary due to friction modifiers. Some guys use it and report no issue tho.
I have seen used oil analysis that are outstanding.
Check out the 2nd page.
http://www.mobiloil.com/USA-English/...ollection.aspx

 

Good discussion thanks for all the feedback guys.

 

Uh...No...the OP`s bike is not made in Japan, but the JASO MA is the only certification for motor oil specifically made for motorcycles.

But any 20w50 oil will be fine in an HD engine. The only bikes that should be using a JASO MA type oil are bikes with flat tappets (oils without zinc additive cause premature wear on flat tappets), or bikes with wet clutches that share the lube with the engine.

 

I use the 15w50 in both my engine and primary for the last 15k miles and have not had any problems whatsoever. I buy it on sale and always have enough to do a couple of changes stored up.

 

this is a good thread, as I have been wondering what oils to use myself and my owners manual confused me even more as it says 15-40 diesel oil is an acceptable oil for the engine. If this is so why are we spending twice as much for a syn "bike" oil when we can get a good syn diesel oil way cheeper?

Steve