man checking his motorcycle

WHY IS MY MOTORCYCLE LEAKING OIL AND HOW TO FIX IT

Motorcycles are meant to be simple, right, so why do they start leaking oil all of a sudden? Engine oil is what lubricates the moving parts of a bike to prevent friction and wear, so it's a pretty important component and leaks can't be ignored.

Oil leaks can be headscratchers because there are so many reasons why they might be happening. However, that's no reason to panic. It's a common problem for riders that everyone has to deal with sooner or later. So let's dive in to see what might be causing the issue.

WHY A MOTORCYCLE LEAKS OIL - COMMON CAUSES

The parts of a motorcycle naturally wear down over time. When dealing with a motorcycle oil leak, there are two main reasons why it might be happening.

  • Worn or damaged gaskets: Gaskets are what seal the different parts of the engine. Gaskets can be found on the oil pan, valve cover, crankcase, or the cylinder head of the engine. A worn or damaged gasket is the most common cause of oil leaks.
  • Faulty plugs: Faulty plugs are the second most common cause of oil leaks. The most common plugs to leak oil are the oil drain plugs, the crankcase plugs, and the valve cover plugs.

HOW TO CHECK AND FIX MOTORCYCLE OIL LEAKS

bike in garage

A complicated issue might require the help of a professional, but simple oil leaks can be fixed with a DIY approach. You'll just need some patience and a few basic tools.

WHERE TO LOOK

We'll assume you don't have any fancy tools lying around to find exactly where the leak is coming from, so here's a simple way to determine the location of the leak.

First, put a piece of cardboard under your motorcycle and see where the oil is dripping. Keep in mind where the gaskets are and hopefully, the source of the leak will be obvious.

If this doesn't help there's always the paper towel method. Wait for the engine to cool entirely then wrap it tightly with paper towels, using tape to keep it there. This method takes a bit of time, so come back after a while and you'll see where the oil has leaked through the paper towel.

STEP-BY-STEP SOLUTION FOR MOTORCYCLE ENGINE OIL LEAKS

In some cases, you'll need to get a bike fixed by a mechanic, but it's possible to fix simple oil leaks all by yourself. You'll just need a few tools and some basic knowledge of the machinery of motorcycles.

A faulty oil drain plug is pretty easy to replace. You can find the replacement part either at an auto shop or online. Just make sure to consult the owner's manual and double-check that you get the right one. It only takes about 15 minutes in the garage to swap out a drain plug.

Likewise, most of the gaskets mentioned above can be changed in your garage. For the valve cover gasket, all you need to do is remove a few bolts and possibly your gas tank as well, which isn't too complicated.

The crankcase gasket and oil pan gasket are simple to change as well. Just check online or in the owner's manual to ensure you're doing it correctly. The process might change slightly depending on the bike you own.

The only thing we don't recommend fixing yourself is the cylinder head gasket. Because it requires taking out the top part of your engine, the pistons and other important parts of the engine will be exposed. A novice mechanic can easily blow their engine while doing this, so stay safe and let a mechanic handle this one.

HOW TO PREVENT OIL LEAKS FROM HAPPENING AGAIN

a group of riders

Oil leaks are simply part of owning a motorcycle, but there are ways to minimize the chances of one happening. The first one is to simply ride your bike regularly. Gaskets that are used regularly tend to last longer.

Keeping up with regular oil changes is also recommended. Old oil has corrosive elements that can harm not only the gaskets but the engine itself. Most oils do contain additives to prevent it from becoming acidic, but these additives dissipate over time.

Lastly, inspect your bike after a long ride or if you haven't checked it over in a while. If oil spots or leaks are forming, it's always best to get on top of it straight away before any major damage can happen.

FAQs

IS IT NORMAL FOR A MOTORCYCLE TO LEAK OIL?

While seepage can occur from time to time, it's not exactly normal for a motorcycle to leak oil. Excessive oil leakage is a sign of a problem that needs to be addressed. It's important to locate the source of the leak and address it immediately so the motorcycle is safe to ride.

CAN YOU DRIVE A MOTORCYCLE WITH AN OIL LEAK?

So can you drive a motorcycle with an oil leak? While the occasional ride with an oil leak won't cause major damage, going on regular rides and ignoring the problem can eventually cause the engine to seize due to a lack of oil inside.

ARE OIL LEAKS WORTH FIXING?

Whether oil leaks are worth fixing depends on the severity of the problem and the history of your motorcycle. A minor leak can be fixed with a simple repair job in the garage, while significant repairs might not be financially feasible, especially for older bikes.

Consider how new your bike is compared to the cost of a repair job. It might not be worth forking out major cash on a busted-up old bike. You'll need to weigh up the cost/benefit of the situation.

HOW MUCH DOES IT COST TO FIX AN ENGINE LEAKING OIL?

Before deciding whether to fix things up yourself or go to a mechanic, it's important to consider how much it cost to fix an engine leaking oil.

Repair costs can vary by the location and severity of the leak, along with the make and model of the bike. Generally speaking, minor oil leaks can be fixed for a few hundred dollars or less. Significant leaks that require major engine repairs or component replacements can end up costing several thousand dollars.

WHAT CAUSES OIL TO LEAK FROM THE CRANKCASE?

The crankcase is the part of the engine that holds the crankshaft and other internal components, and it's sealed by gaskets and seals to stop oil from leaking out. 

Worn-out or damaged gaskets are the number one reason for oil leaks from the crankcase. Damaged crankshaft seals can also be the culprit. Crankshaft seals are designed to prevent oil from leaking out of the engine at the crankshaft, so if they become worn out or damaged it can lead to oil leaking out.

The problem might also be as simple as an overfilled oil level. If the oil level is too high, it can cause excess pressure in the crankcase which creates oil leaks.

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