Stock jetting is lean especially on the slow jet. Can move up to a 45. A 45 slow and 120 main is the standard if the air snorkel is removed.
Lube swing arm and linkage bearings as well as fork head bearings.
oil: 10w40 every 1000km / 30hours. a semisynthetic motorcycle oil is cheap and safe
air filter: clean and lube when dirty. check it at least every 5-10 hours (after any ride if you ride in mud and sand).
chain: clean and lube after any ride. Wd40 is not a good lubricant. prefer a specific lube. a spray or, better and cheaper , an high viscosity gear oil.
slack should be 1 inch with the bike on the kickstand (push down and measure from swingarm, push up and measure from swingarm. difference should be 1 inch)
valve clearance: every 2000km / 60hours
brake oil: once a year
plug: once a year
tire pressure: every 15 days
fork bleeding: every month
Recommended for basic trail riding:
Front: Bridgestone ED11
Rear: IRC VE-33 rear.
Pirelli MT16 for front and rear was also recommended.