I change the oil on my bikes at 3,000 miles, which is close to the 6,000km(3,700mi). I don't abuse the bikes and may be changing early, but this is what I'm comfortable with. If I'm on a trip, I may go over the 3,000 miles.
The owner's manual says 10,000 km or 6,000 miles. Yamaha engineers, builds, and warranties them with this recommendation, but most of us change before then because it makes us feel better.