How Often to Change Primary Oil in Harley-Davidson Bikes


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How Often To Change Primary Oil In Harley

Are you a Harley-Davidson biker struggling to figure out how frequently you need to change primary oil in Harley-Davidson bikes? If yes, then this is the right place for you to be.

Changing primary oil in Harley-Davidson bikes is easy as long as you know the right procedure. Harley-Davidson recommends that you should change the primary oil after every 5,000 miles of riding. However, many also say that semi-synthetic oil lasts between 5,000 to 6,000 miles before you have to change it, but you can still stretch it to 8,000 miles. Meanwhile, fully synthetic oil could increase the mileage of your oil change interval slightly, and last between 7,000 and 10,000 miles.

In this article, you will get to learn all about primary oil in bikes, why do you need primary oil in your bike, how often to change primary oil in Harley-Davidson bikes, how to change primary oil, and more. Stick around to get all the answers that you are looking for.

Primary Oil in Harley-Davidson Bikes

Harley-Davidson bikers often ask about how they can improve their motorcycle’s performance. They are looking to know if changing their riding style, adding a series of high-tech accessories, or riding their bikes only in perfect riding conditions will improve things. However, the answer is more obvious than that.

The best way of getting the most out of your Harley-Davidson bike is to perform regular primary oil changes as per Harley-Davidson’s maintenance schedule. It is pretty simple, but there are a few things that you will need to know about when it comes to primary oil in Harley-Davidson motorcycles.

Difference between Different Types of Motorcycle Oils

Motor oil will lubricate the engine and ensure smoother and more efficient running. Its composition mainly includes synthetic oil and mineral oil. You will have to change the motor oil once every 5,000 miles for the proper functioning of the engine.

Heavy synthetic gear oil will lubricate the transmission gears. It is a blend of mineral and synthetic oils. You will have to change heavy synthetic gear once every 30,000 miles

Motor oil is essentially a lubricant that is used in internal combustion engines, which will power most vehicles. Many types of motor oils include synthetic, conventional, and blend. Viscosity is the main difference between motor oil, primary oil, and synthetic gear oil.

Conventional motor oil is a common type of motor oil and its composition is of refined crude oil that contains additives for performance improvement. Synthetic oil is made up of synthetic chemicals, and it is free of crude oil. This type of oil often outperforms motor oils, but it is also more expensive. The blends are a mix of natural and synthetic oils. 

Heavy synthetic oil will be ideal for automotive transmissions and differentials. They typically have a higher viscosity than motor oils for providing better protection for gears.

Why do you Need Primary Oil in your Harley-Davidson Bike

If you are a Harley-Davidson biker, you need to know the importance of oil changes for maximum protection and efficient performance. However, did you know that using primary oil is just as important?

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Primary oil is important for lubricating the transmission and engine. It will help cool the engine by carrying the heat away from critical components. But over time, the primary oil ultimately breaks down and ends up becoming less effective. This is why it must be changed regularly.

But how to choose the right primary oil for your bike? There are a few things that you need to consider when you are choosing the primary oil option for your Harley-Davidson bike.

First, you have to ensure that you pick a primary oil option with optimal viscosity and additives. You need to check the owner’s manual and see which viscosity level your bike needs.

Secondly, you should consider the price. You wouldn’t want to spend a lot of money on oil, but you shouldn’t skimp on quality either.

How Often to Change Primary Oil in Harley-Davidson Bikes

Harley-Davidson recommends that you should change the primary oil on its bikes every 5,000 miles under normal riding conditions. However, if you frequently ride your motorcycle in extreme weather conditions like cold weather or hot weather or at high speeds, you might have to change the oil more often.

To answer to how often to change primary oil in Harley-Davidson bikes will depend on what type of oil you’re using. Semi-synthetic oil usually lasts between 5,000 to 6,000 miles before you are needed to change it. Sometimes, you might even be able to stretch it to 8,000 miles. Fully synthetic oil will increase the mileage of the oil change interval to somewhere between 7,000 to 10,000 miles

Will less frequent riding buy you some extra time before needing to change the oil? No, not really. Fresh oil is essential to a long lifespan for your Harley-Davidson bike. The general rule of thumb would be to change the primary oil twice per year.

Symptoms that your Harley-Davidson Bike Needs Primary Oil

If you’re a proud owner of a Harley-Davidson motorcycle, you should remember that your motorcycle requires regular maintenance for smooth running. The maintenance will include scheduled maintenance and regular oil changes. But how to know that it’s time to change the primary oil? Here are some of the signs that will tell you that your bike needs oil.

1. Dry primary chain

In case you notice that your bike’s primary chain is dry, it means that your bike requires primary oil. Lack of lubrication can easily cause the breaking of the chain, which leads to damage to your engine.

For lubricating the primary chain, you should top off the oil as needed. In case the chain is already dry, you should clean it and add fresh primary oil.

2. Hard to engage the first gear

In case it is hard to engage the first gear, your Harley-Davidson bike could require primary oil. While hard first gear can happen due to many reasons, a low primary oil level is often the common reason.

3. Oil on primary drain drug

In case you see any oil on the primary drain plug, this will indicate that your Harley-Davidson requires primary oil. The oil will keep the clutch pack lubricated and prevent any metal-to-metal contact for proper function.

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If you’re low on oil, you might notice unsmoothed engagement of the clutch or your motorcycle might shift stiffly. If you don’t add more oil, the clutch park could fail and need replacement because of friction.

How to Change the Oil in your Harley-Davidson Bike

So, you have checked the primary oil and see that it is dirty, or it has got low levels and needs to be changed? Of course, you will think to yourself that you need to get the oil changed quickly.

Changing the primary oil in your bike is easier than you think. The process is so easy that you shouldn’t even think of taking your bike to a mechanic and paying a huge fee for the oil change. You can carry out the entire process on your own, with only a few basic tools.

Necessary tools that you will need

  • Primary oil
  • Brand-new oil filter
  • Oil tray/drain pan
  • Oil filter removal tool
  • Torque wrench
  • Funnel 
  • Socket and wrench 
  • Gloves
  • Rags for cleanup

Once you have armed yourself with the necessary tools, and you are ready for the job, you should follow these steps to change your primary oil.

Steps to Change the Oil in your Motorcycle

Step 1: Prepare your bike

Ready your bike for the oil change by balancing it on a stand. You can use the front, rear, or center stand. After that, put an oil tray directly under the bolt where old oil would drain without creating a mess.

Remember, draining warm oil will be easier as it is less viscous. You should consider letting the engine run for 5–10 minutes and allowing the oil to get warm.

Step 2: Open the drain plug

Now, you should the socket and wrench and use it for opening the engine drain plug. Do so by turning it in an anti-clockwise direction. Remember that you should remove the washer while you’re at it and place the plug someplace you can easily trace it.

Avoid coming into contact with the hot parts of your motorcycle if you started by running the engine and allowed it to warm up.

Step 3: Let the old oil drain

Now, you should allow the old oil to drain completely out of your motorcycle. You can sit back and allow it to drain on its own, or you could even consider tilting the bike to remove any undrained oil bits.

Step 4: Remove the old oil filter

Now, you need to remove the old oil filter. Grab a wrench and plait it to the filter before unscrewing it in an anti-clockwise direction. Once you have removed the filter, you should expect old oil to come out of it. Allow it to drain completely, too.

Step 5: Install the new filter

Now comes the time to install a new oil filter. Once you’re satisfied that the filter/plug housing is drained out completely, you should take the new filter and smear some of the new oil onto its sealing rings with the help of your fingers. Now, screw the new filter manually before attaching the adapter with a wrench installed to tighten it.

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Step 6: Put back the drain plug

Now comes the time to put back the drain plug. You need to refit the new washer to your drain plug before screwing it into the sump manually. Make sure that you’re using the torque wrench (check the torque setting recommended by the manufacturer) to tighten it fully.

Step 7: Fill fresh oil

Person Filling Harley-Davidson Motorcycle With Fresh Oil

Fill the engine with fresh oil. You will need to remove the plug on the engine oil input, insert the funnel, and then start pouring the oil. Again, you will have to consult the user manual on the manufacturer’s recommendations for the oil capacity to avoid overfilling.

But remember one thing, once you’ve filled up the oil to the maximum level, you must leave the engine running for around 5 minutes. Moreover, ensure that you confirm that the oil pressure light has gone out after starting the bike. Turn off the engine and then check the oil level once again and adjust accordingly.

Once you’ve taken your bike for the first proper drive after the oil change, you need to check the level once more. You should see if it is at the maximum level.


What is primary oil?

Primary oil is the lubricating oil used in Harley-Davidson bikes. It largely consists of petroleum and other additives. When pumped, it goes from the crankcase to the transmission before going to the clutch, where it lubricates and cools the engine components.

What happens if you do not change the primary oil on time?

If you don’t change your Harley-Davidson bike’s primary oil on time, it caned up, damaging your bike. Fresh primary oil will lubricate the transmission and clutch.

If you allow the oil to get too old, it can start breaking down and form sludge. It could clog up the transmission and create problems with shifting gears. Moreover, it can lead to premature wear on the clutch plates.

In other words, you must change the primary oil on your Harley-Davidson bike on time if you want smooth performance.

How to decide the right weight viscosity of the primary oil?

It is important that you decide the weight viscosity of the primary oil, as it affects the overall lubrication of the engine. The lower the weight viscosity, the thinner will be the oil, and the easier it’ll flow. Meanwhile, the higher the weight viscosity, the thicker will be the oil, and the harder it will flow.

If you have a high-performance engine, you will want to use a lower-weight oil for better lubrication and easy flow. If you have a standard engine, you’ll be able to use a higher-weight oil without any problems.

How much does it cost to replace primary oil?

The average cost for a primary oil change replacement will be between $75 and $200. It will include the cost of the oil, filter, and the needed labor. The cost will be affected by the oil type, the bike’s model, the build, and the service center’s location.

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