Why Is My Motorcycle Leaking Oil? – Causes and Fixes

 An accumulation of wear and tear over time to different components is among the many causes of oil leaking from your motorcycle. Finding the real source of these leaks and effectively fixing them is the best thing you can do for your bike.

Read on for more on the reasons why your motorcycle is lacking and what you can do about them.

A puddle of oil underneath you motorcycle is annoying as it is dangerous. This leaking could act as a precursor to several issues when left alone or even an indicator of problematic components or function.

In this guide, we are going to walk you through the surrounding elements of a leaking motorcycle including the source of these leaks, and what you can and should do about them. Take a look at our guide on why your motorcycle is leaking for further insight on the topic.

Why is my motorcycle leaking oil? Please read on for a few genuine ideas on how to sort out oil leaks on motorbikes.

While they aren’t as complex as cars, motorcycles are intricately built machines that also have annoying problems such as leaking. These can be messy and quite annoying, especially if you use your bike regularly or plan to.

Among the biggest reasons your bike is leaking oil might be faulty gaskets. When the gaskets on your engine especially the cover gasket, oil pan gasket, cylinder head or even crankcase gasket is problematic, then leaks develop.

The gaskets we’ve mentioned experience the greatest internal pressure when your bike is operational. Because of this, oil will easily push between them if they are not in top shape.

The other reason your bike might be leaking oil is the popular wear and tear. Most components if not all age and overtime become less effective. When this wear accumulates these components will not perform their jobs as well as they did when they were brand new.

Most of these parts including gaskets sometimes have a lot of pressure put on them, and develop weak spots eventually. These weak spots are often the reason for your bike leaking.

Tip: Never allow your bike to remain dormant for extended periods of time. This will harm your gaskets rather than buy them time. These parts often need to be warm and expanded. When left alone for too long, they become aged, dry and brittle, and therefore more prone to leaks.

Lastly, another core reason you might be experiencing oil leaks on your bike is faulty oil plugs. Usually, the oil plug on the bottom of your drain pan is prone to these leaks.

Additionally, oil plugs on the side crankcase and valve cover are also likely to create leaking issues. Damage to the oil plug will trigger these leaks. Additionally, if these plugs are no longer tightly installed or even faulty, then they can no longer function properly, to keep oil inside your bike.

Often vibrations of your motorbike or overtime degeneration will heavily contribute to these rings becoming loser and eventually leak oil.

How does the motorcycle engine work and why it needs oil

If you are a newbie to motorcycle engines, consisting of a similar concept of pistons, cylinders, an engine block: the works. On bikes, the engine works by moving pistons in an up and down motion within the cylinder block.

These in turn turn a crankshaft which effectively transforms the energy produced from this motion to a rotary motion.

Through the transmission, this rotational motion is transmitted to the rear motorcycle wheel. Like car engines, bike engines have a system of classification based on the number of cylinders they carry, and the capacity on each engine.

Similarly, engine oil plays many roles in motorcycle engines as it does in the car engine. When it begins to leak out of your bike, then the engine cannot properly perfom. It is important to remedy these leaks as soon as possible to ensure the performance problems do not arise.

Most common locations for oil leaks

Aside from noticing the oil stains on the ground, you might notice the leaking from observing the components. Among the most common areas you can check for any leaking include the following parts:

Hoses and tubes

When any hoses or tubes become aged and brittle, then they can easily cause leaks all around. Normally, oil is channeled through said hoses/tubes and will leak out at connection points or along the hose it this component isn’t in top shape.

Various gaskets

We have already mentioned the role gaskets have in creating leaks. The cylinder head gasket especially is the gasket found between the oil can cover and engine block and is a popular leak location on many bikes. Additionally, the oil pan seal and gasket are usually prone to wear and become very dry and brittle as time goes by, leading to leaking.

Oil filter

The oil filter interacts with your oil a lot. However, it can become loose, cracked or even broken. This leads to issues with escaped oil and these leaks.

Checking for and mixing motorcycle oil leaks

The first step in fixing a leak is identifying where it is coming from. Luckily, you can easily do this at home granted you have some knowledge of bike maintenance.

Usually, the first step is identifying the type of leak you have but since we are dealing with engine oil leaks, then you can go ahead and skip this part.

Additionally, you must clean the engine and engine area well before you can begin the process. Different motorbike fluids, essential to operation, have a variety of colors which every bike owner must be aware of.

Begin by flushing dye into the suspected system, ensuring to follow the information and guidelines provided by the leak testing kit. In this case, you will start by adding the dye into the engine oil compartment and then proceed by letting the engine run for some time.

After impregnating the engine with the dye, then you will proceed to shining a black light on the area. This will highlight the dye previously introduced and help you find the exact leaking location. Depending on the dye leak testing kit, the highlighted are will shimmer a bright green or yellow when illuminated with black light.

Helpful pointers

While conducting the check isn’t difficult, there are several helpful tips we’d love to share for all beginners or experienced DIYers who plan on checking their engine for leaking:

Always work clean. Like we already mentioned, always clean around the engine components before you begin the check. When you start on a clean engine, then you can easily observe areas causing leaks or even developing any build ups.

In addition to cleaning the engine, always remember to leave a cardboard or a bunch of newspapers underneath your bike when you do the UV dye test. These should catch the runaway oil leaking from your motorcycle.

You might be relying on the leak detection kit to check for leak but a though eye inspection might also come in handy. We often recommend beginning with an overall check to help with diagnostics. Once you’ve fully inspect your motorcycle, then you might have a rough idea of where any and all leaks are coming from. The dye will then confirm this and help you fix the area appropriately.

Fixing your motorcycle’s engine oil leaks

Now that you’ve determined where the leak is coming from, repairs and replacements are in order. You can decide to do these on your own or to go to a professional shop where they will fix the issue.

However, we often advise that you schedule an appointment with a pro if the gaskets are the source of your leaks. Because they have the best knowledge of the most appropriate components to use, they will make sufficient judgments that ensure your leaking problems are properly fixed.

What happens next when oil leaks from the exhaust?

The last thing you want is to experience an oil leak from the exhaust nonetheless. This phenomenon will arise due to a number of reasons including the following:

  • When you have a greater proportion of oil to gasoline, then the result is an oil leak from the exhaust. This is the engines way of removing the excess oil from the compartment.
  • A problematic carburetor float, a tilting member which sits on gasoline also known as the float. When at an unchecked level the float will not conduct its duty which is to close the valve responsible for blocking the gasoline supply.
  • Broken and deteriorated crankshafts or seals are often responsible for leaks through the exhaust.

Checking the oil level on your motorcycle

Like with a car, it is essential to keep tabs on your engine oil levels. This information will come in handy when you suspect leaks and other issues related to the oil levels on your bike. If you do not know how to check the engine oil levels on your bike, then here is a quick guide to performing this necessary check:

  • Begin the check after the oil has circulated. The engine doesn’t need to be hot, nor does it need to be cold. When it is sufficiently warmed, about 15 minutes after your ride, you can start the check.
  • With your bike in upright position, you will begin the check. Ensure you do not support the bike while doing this check.
  • Using a clean and freshly wiped dipstick, insert and draw the stick from the bike, and proceed to read the result.

TIP: Dip sticks are made with maximum and minimum value indicators that tell you where the oil level sits. Additionally, you are advised to check your oil levels regularly, especially if you ride on all sorts of terrain or experience hotter climates.

Topping off oil on your motorbike

If you find your oil levels below the minimum, then you must top it off to the required levels. However, simply topping off a leaking bike might be a senseless expense. Ensure the leaks are properly handled before you go on.

Next, you want to select the best engine oil for your motor bike. Do not get flustered by all the different types available.

Next, you want to unscrew the the oil cap and then remove it. After which you can add the fresh oil gently until it has reached required levels. Ensure to stop and check whether the oil is a good level before adding more.

Tips on choosing the best engine oil for your bike

There are several types and brands of motor oils, all of which have varying capabilities. Using the oil grading system used to classify different engine oils, you can easily tell these apart. However just because it’s great on paper doesn’t mean it’s great for your machine. In fact, here are some tips to help you find the best engine oil for your bike:

Factory recommendation

What you want might not necessarily be what you need. Using the manufacturer’s recommendation as a guide, select the best suiting oil that is factory approved. This means the oil you select must have specs similar to the factory recommended option.

Riding style and surrounding environment

Because the way you ride and the ambient temperatures actively influence the performance of your oil, it is essential to make choices that account for these factors.

Grade and additives and other specs

Oil specifications and grades are important to the user. These will help you find the best possible option based on the specifications for your ride. Apart from the grade or even additives, good oil choices are compliant  with requirements from various body are essential to let you know that the oil has undergone various quality checks to ensure it is up to standard.

How much does it cost to fix an oil leak on a motorcycle?

The cost of getting your motorcycle fixed for leaking varies depending on a number of factors including the type of bike you own, the shop you visit or even the source of your leaking problems.

If you are not handy with bike parts, we recommend that you get these parts repaired at a shop, especially if the gaskets are the cause for this leaking. For example, replacing a filler cap will cost you under 40 dollars. However, issues with the main seal or event gaskets will result in hundreds of dollars in expenses for repairs.

Final word

Oil Leaking from your engine is among the worst things that could happen to it. The best thing you can do for it to properly diagnose and fix this leak. Our guide should properly equip you if you are experiencing a leak or even suspect one. If you can, make the fixes to stop the oil from leaking from your engine, if not, ensure you have your bike inspected and properly fixed by a pro.