Harley Davidson Primary Oil Substitute [Top 3 Picks]

It is important to select the right Harley Davidson primary oil for your bike. There are many primary oils to choose from, so it can be difficult to choose the best one. What is the best Harley Davidson primary oil substitute?

The best Harley Davidson primary oil substitutes are as follows:

  1. Mobil 1 Racing 4T 10W-40 oil – Click here to see it on Amazon – our #1 top pick!
  2. Mobil 1 V-Twin 20W-50 Oil
  3. AMSOIL Synthetic 20W-50

Read on to learn more about the function of primary drive oils in Harley Davidson motorbikes, their importance, the different brands of primary oils for Harleys, and how to change the oil.

Also, take a look at our top Harley Davidson primary oil substitute on Amazon, the Mobil 1 Racing 4T 10 W-40 Oil, to see its price and great reviews:

Click here to see it on Amazon.

Best Harley Davidson Primary Oil Substitute

harley davidson primary oil

To protect the primary drive, you need to use the best primary oil that is available. Your Harley is an expensive bike that provides high-quality drive to you and your passenger. To ensure that it will always run at its optimum, you need to give it the best tools to will enable it to function optimally.

Here are some of the best primary oils that you can use to ensure that the primary drive of your Harley will be working at its best.

1. Mobil 1 Racing 4T 10W-40 oil

One of the most highly recommended primary oils for Harley Davidson motorbikes is the Mobil 1 Racing 4T 10 W-40 Oil.

Click here to see it on Amazon.

This oil is specially designed to enable your Harley to run with maximum efficiency by ensuring that your engine is always clean.

It is made for cruiser and sport motorcycles.  If you are using your Harley for long drives or short races, this oil will ensure that your primary and engine parts will be able to endure high temperatures.

2. Mobil 1 V-Twin 20W-50 Oil

Another great Harley Davidson primary oil substitute that will protect your primary drive is the Mobil 1 V-Twin 20W-50 oil.

Click here to see it on Amazon.

This oil is specifically designed for motorbikes with separate engine lubrication systems. But you can also use it with bikes of standard engine and transmission lubrication systems.

It will also provide the correct frictional qualities required for motorbikes with a moist-clutch engine and transmission systems.

3. AMSOIL Synthetic 20W-50

Amsoil’s synthetic oils are also some of the best in protecting the primary drives and engines of Harley Davidson motorcycles. In particular, the AMSOIL Synthetic 20W-50 is most suited for this purpose.

Click here to see it on Amazon.

This is a fully synthetic oil that can efficiently withstand heat. It will reduce wear in the metal parts of hot running motorbikes.

Harley Davidson Heavy Synthetic Gear Oil

There is primary oil that Harley Davidson formulated. They know the material they used for the primary drive. Thus, they know the best type of oil that will provide the best protection. It is tested and certified for use in the primary chain cases and transmissions of Harley motorbikes.

This is heavy synthetic oil designed for use in extreme temperature environments, such as cold weather and desert heat, heavy load riding applications, and frequent two-up riding conditions.

The oil grade is SAE 80W-140 dual viscosity heavyweight and primary oil. It has proprietary additives and pure synthetic base stock that makes it flow better at a cold start-up. Its Harley Davidson primary oil weight is the best. In high temperatures, its viscosity acts like a 140 weight oil which can provide maximum protection.

The problem is that this oil can be hard to find and expensive. So instead, you can choose any of the substitutes listed above.

How to Change the Primary Oil in Harley Davidson Motorcycles

harley davidson primary oil substitute

Harley Davidson motorbikes are quite expensive. They are different from the common motorcycle in many respects. To run efficiently, it requires the tools and materials that will best protect it from outside disruptive elements.

Harleys are not unit-constructed bikes. Their engines and transmissions are not combined into one single assembly. The engines and transmissions of Harleys are separately constructed and assembled. Their engines are separately assembled from the transmission and the clutch.

That is why they need lubricating oils designed for the engine and another for the transmission. Each separate system has to be fed with its own oil type. And for safe operations, you should replace them every 2,500 miles.

When changing the primary oil, it is recommended for you to warm the engine first. You need to bring the engine to its normal operating temperature. It will ensure that the oil cooler thermostat will open up so that the previous oil will drain out properly.

Prepare the Following

Changing the primary oil yourself will enable you to save money. This is a fairly straightforward task that you are perfectly able to perform. But before going on to drain and change the primary oil, you need to prepare the following things.

  • New motorcycle primary oil
  • New oil filter
  • Funnel
  • Oil drain pan
  • Filter wrench
  • Socket kit
  • New primary case gasket
  • New O-ring
  • Hammer
  • Torque wrench

1. Place Your Bike on Level Ground

Put your bike in a place where there is level ground. The place should also be well ventilated, not to be bothered by the smell of the lubricating oil. Start the engine so that it will operate as it used to. This will help drain out the old primary oil easily.

2. Position the Bike for Draining

Put the bike into a position where you can start draining the old oil out. A vertical position will be the most ideal. If the bike is on a kickstand, straighten it out to assume an upstanding position. This will enable the old oil to drain out easily.

3. Remove the Primary Case Cover

Find the primary oil drain plug. It should be right below the primary case. Use a socket wrench to unscrew the primary case cover. Typically, there are five bolts that you need to unscrew. Set these bolts and the primary cover aside.

4. Remove the Old Primary Case Gasket

Remove the old gasket on the primary case cover. Just pull it out from its place. Clean the cover and then put the new gasket on the cover. It should easily drop into place. Set the cover aside.

5. Remove the Drain Plug

Place the drain pan directly under the opened primary casing. Use a 5/8 inch socket wrench and loosen the drain plug. Once you feel it is easy to unscrew, remove the drain plug with your hand. See to it that it doesn’t fall into the oil pan. Clean the drain plug.

6. Drain the Old Primary Oil

Position the drain pan so that it can directly catch the draining oil. Drain out all the oil completely from the primary casing.

7. Screw Back the Drain Plug

Once the old primary oil is completely drained out, you need to screw that drain plug back in its place. But before doing that, install the new O-ring on the drain plug. Use your hands to do it. Then use a socket wrench and a 5/8 inch socket to tighten the plug to its original place. If you are using a torque wrench, set it to 14 to 21-foot pounds to tighten the plug.

8. Refill the Primary Case with New Oil

Once the drain plug is tightly screwed on the drain hole, start pouring in the new primary oil in the required amount. Visually check if the fluid is at the right level. The primary oil should be touching the bottom of the clutch plate.

9. Put Back the Primary Cover

Place the primary cover back on its position and then hand-tighten its five bolts. Then use a torque wrench set at 14 to 21-foot pounds of torque to tighten the bolts. Use the star pattern in tightening these bolts.

When to Change Your Harley Davidson Oil?

harley davidson primary oil weight

Generally, all bike manufacturers recommend changing the oil every 5,000 miles. Harley says it should just be after every 2,500 miles. Other than that, other signs will tell you if your motorcycle needs a primary oil change:

1. The Primary Oil Looks Black

If your primary case cover has a window or your motorcycle has an oil dipstick, check the oil color. Good oil still has a translucent brownish color. But if it is already black and opaque, you need to change it at once.

2. It Feels Gritty

A good oil will feel smooth on your fingers. But if you notice some grittiness on it, you need to change it promptly.

3. Transmission Runs Louder Than Before

If you notice that the transmission is running louder than before, the oil must have already gone bad. A transmission system will sound good if the oil is still good. But if the sound deteriorates, one of the culprits is bad lubricating oil.

About Harley Davidson Primary Oils

A Harley Davidson motorcycle is a beautiful piece of machinery that you should maintain very well if you want to take advantage of what it has to offer. One of the chores that you should not miss is changing its primary oil.

Mobil 1 Racing 4T 10W-40 Oil

One of the best primary oils that you can use for Harley Davidson bikes is the Mobil 1 Racing 4T 10W-40 oil. You can also choose to use the Mobil 1 V-Twin 20W-50 oil. Either one of these two oils will do a great job of lubricating the primary drive of your Harley.

Click here to see it on Amazon

AMSOIL Synthetic 20W-50 Primary Oil

For Harley twin-cams, the AMSOIL Synthetic 20W-50 primary oil goes highly recommended. You can use them in all three holes in your motorbike. Amsoil has now produced a dedicated fluid you can use in Harley motorbikes’ transmission and primary cases.

Why do you need to use primary oil in your motorcycle? The primary gets very hot when the motorcycle is running. As you know, metal expands when subjected to high temperatures. The primary oil, aside from helping to reduce friction, also helps to cool down the temperature of the primary drive components.

If you don’t use the right primary oil in your Harley, you will eventually experience problems with your primary drive. The recommendation is to use the best primary oil and to change this oil every 5,000 miles.

Why the Primary Drive of a Harley Davidson Needs Lubrication

The primary drive of your Harley is composed of a pulley or engine output sprocket, which is attached to the crankshaft of the engine. Also included in the primary drive parts are the roller chain belt, the clutch assembly, and the housing or casing that holds the whole assembly. The clutch engages the primary drive to the transmission.

All these primary drive components move in sync when the motorbike is running. And when a Harley is running, heat is generated by the metal parts inside its engine and drive components because of the speed by which they are running.

Typically, the temperature of the primary drive at the rear and over the clutch when the motorbike is running is measured at around 98°F. At the front, where the engine block and crankcase are located, the temperature is measured at about 103°F.

Meanwhile, the measured temperature at the inner primary drive (where the compensating sprocket is located) is around 174°F.  As you well know, metal parts that are subjected to heat expand. You need to lubricate these parts with oil so that there will be a friction reduction between them. The oil will also help to control or cool down the heat generated by these metal parts.

The primary gets so hot when you drive your Harley. As you know, metal expands when they are subjected to high heat. The primary oil, aside from being a friction aid, also helps to cool down the temperature of the primary drive.

Conclusion: Harley Davidson Primary Oil

If you own a Harley Davidson motorcycle, there are several primary drive oils that you can use. One of your best choices is the Mobil 1 Racing 4T 10W-40 motorbike oil. You can also choose to use the Mobil 1 V-Twin 20W-50 primary oil.

Harley Davidson also makes its own primary oil. It is specifically designed to protect and prolong the life of their primary drives.

Again, here are the steps you can follow to change your Harley Davidson Motorcycles’ primary oil:

  1. Place Your Bike on Level Ground
  2. Position the Bike for Draining
  3. Remove the Primary Case Cover
  4. Remove the Old Primary Case Gasket
  5. Remove the Drain Plug
  6. Drain the Old Primary Oil
  7. Screw Back the Drain Plug
  8. Refill the Primary Case with New Oil
  9. Put Back the Primary Cover