1. Start the engine and let it run for several minutes to heat the oil. This will help the oil drain quickly and completely.
2. Engage the motorcycle in neutral and place it on its side stand (jiffy stand). Ensure that the oil drain pan is adequately placed under the drain plug before you proceed.
3. Look for the drain plug. The oil drain plug on the 2004 Road King Custom is located on the bottom of the oil tank, near the front of the engine.
4. Remove the drain plug. Use the correct wrench or socket to loosen the oil drain plug. Be careful not to drop the oil drain bolt into the oil drain pan.
5. Allow the oil to drain. Allow the oil to drain completely into the oil drain pan. This may take several minutes. Oil may come out quickly for a short period, so ensure the oil pan is big enough.
6. Reinstall the drain plug. Once the oil has stopped draining, reinstall the oil drain plug. Ensure the drain plug is tightened snugly to prevent leaks.
7. Dispose of the old oil responsibly. Take the used oil to a recycling facility or service center. Do not pour it down the drain.
8. Add new oil. Use a funnel to add the recommended amount of new oil to the motorcycle. Check the oil level with the dipstick to ensure you do not overfill the oil.
