I use mobile 1 synthetic, 20/50 wt. Just love it, the clutch works better. It's 13$ a liter from Wal-mart, that and a new filter every 2000 km. Don't forget to clean the sump screen-filter on the shifter side. The one on the clutch side doesn't have to be cleaned that often. I believe it holds approx 1800cc for a full oil and filter change.