Well if the previous owner took good care of his bike all you really need to do is change the oil and oil filter. However if you wanna stay on the safe side (which I would recommend) / if the previous owner didn't keep up with maintenance I would definitely also check the coolant level, air filter, check/tighten spokes, check the torques of all the most important parts, check chain slack. if you want, depending on how old the dot4 is, change the brake fluid, made quite a difference for me.
those are the things my yamaha dealer did at the 1000 km check which was included in the buying price. (except for changing the brake fluid which I did at 12,000 km)