your owners handbook should specify oil type,but really 10/40,or10/30 should be ok,try and find one that says A.P.I.S.G,the s.g. rating refers to the viscosity,or how slippery the oil is.anything over s.g.,won't lubricate as well,and could cause a slipping clutch.there was a bit of a saga with honda and i believe,kawasaki on this to do with different oils.the trick is to change your oil and filter,regularly
