Hi Guys
I replace my engine oil once a year on my XS 400 DOHC.
I run between 4000 and 6000 km per year.
I use Castrol Power 1 racing 4-T 10W50, Syntetic engine oil for MC.
I think it's OK, works fine no significant oil consumption, of cause I'm aware of the service manual says 3000 km...