How do you change oil on RM85?

To change the oil on a RM85, first warm up the engine to allow the oil to drain more easily, then turn off the bike and let it cool slightly. Place a drain pan under the oil drain plug, remove the plug, and let the old oil fully drain out. Replace the drain plug, then remove the oil fill cap and pour in the new oil through the specified fill hole, ensuring you use the correct type and amount as per the owner's manual. Finally, check the oil level using the dipstick or sight glass, and replace the fill cap securely.