Do you use motorcycle oil in your ATV?

[sHERM]

My manual for my King Quad calls for 10w-40 with an API of sf, or SJ or a JASO of MA. I've been using 10w-40 API SM. ( Havoline)

I think the JASO specified for clutch and transmission lube, which is done by the crankcase oil.

Am I hurting my Quad by using regular car oil in it?

 

[arob85]

Not hurting anything, although I would recommend one of the 15w40 diesel rated oils. They are likely better than the vast majority of motorcycle oils. They have proven to be very shear stable in ATVs. Rotella has the JASO rating if you are worried about the clutch.

 

[sHERM]

This is an interesting read on this subject.
http://www.dirtrider.net/forums3/text/topic/146867-1.html