
20W-50 Synthetic V-Twin Motorcycle Oil
Excellent in air-cooled motorcycle engines due to high heat resistance.
Tell us what you ride, and we’ll tell you what to use. Find the best oil for your bike using the Motorcycle Lookup Guide.
For this demonstration, we’re using a 2014 Harley-Davidson Softail Fat Boy Lo with a 103-ci engine. Before you begin, it’s a good idea to start your engine and let it run for a bit. This will warm up the oil so it flows easily when you’re ready to drain it.
On Softail models, the oil reservoir is located under the seat. Look directly below the seat– and slightly behind it – underneath the frame to find the oil drain plug. Use a ratchet and 5/8-inch socket to remove the drain plug. Once loose, finish removing the plug by hand to avoid dropping it into the oil pan. Remove the oil reservoir cap to increase oil flow.
Place the bike in a vertical position to drain all the oil. If you’re working on a lift, you’re okay. But if you are working with the bike on its kickstand, straighten the bike to an upright position to ensure removal of all the oil.
Next, remove the oil filter. Place a few rags underneath the filter to catch any drips. You can also slide the oil pan underneath to catch oil that drains from the filter.
Loosen the filter using a ratchet, 5/8-inch extension and filter wrench. Finish removing it by hand and quickly move it into your oil pan. Take some shop towels and clean up any residual oil that may have spilled when you removed the filter.
Next, apply a thin film of oil to the gasket on the new filter. Don’t overdo it. You want a light film to ensure a proper seal when you put the new filter back on.
Thread the filter onto the engine until you feel the gasket draw snug. Turn it another half to three-quarters of a turn to complete the install.
Clean the residual debris from the drain plug, install a new O-ring and thread it back into the engine. Snug it up, then use a torque wrench to finish the install. The torque wrench should be set at 14 to 21 foot-pounds of torque.
Now it’s time to add oil. The Softail calls for three quarts of oil. Start with 2 1/2 quarts. It’s very important not to overfill the reservoir. Next, take the bike for a short ride to bring the engine to operating temperature. Check the oil level and top-off as necessary. Remember to check the oil while it’s hot and the bike is on the kickstand.
Once it’s topped-off, insert the dipstick and check the fluid level one more time.
For your specific bike, consult the owner’s manual for oil capacity and viscosity, or check out the AMSOIL Product Guide.
Excellent in air-cooled motorcycle engines due to high heat resistance.
Designed to install and remove AMSOIL Ea Oil Filters and Ea Motorcycle Oil Filters in hard-to-reach locations.
The unique construction and full-synthetic media of Ea Motorcycle Oil Filters allow them to provide excellent performance in motorcycles and other powersports equipment.
Designed for those who demand the absolute best lubrication for their motorcycles.
Designed to improve startup performance and eliminate engine ping and knock for increased power at low-rpm operation.