Why Is My Motorcycle Popping on Acceleration?

“Why is my motorcycle popping on acceleration?” is the question many motorcycle owners ask. This problem is due to excessive fuel in the engine, a dirty fuel filter, or clogged fuel injectors.

Finding the exact cause of the problem can be difficult, especially if you’re not technically inclined. Our automobile team discusses the possible causes of a backfiring motorcycle and how to fix it.

Why Is Your Motorcycle Popping or Backfiring When Accelerating?

The possible causes of your motorcycle popping or backfiring when accelerating include too much or too little fuel in the engine. A bad fuel pump, injector, and dirty filter also contribute to the problem. You could also be dealing with damaged valves.

You can decipher a popping sound by noting if it comes from the exhaust system. A popping sound occurs during combustion in the intake hose due to an intake leak. The popping sound isn’t as loud as a backfire, and there are usually no flames in the exhaust pipe.

– Excess Fuel in Engine

An improper fuel ratio doesn’t just include low fuel. Excess fuel in the engine can also cause problems for your motorcycle. In this case, your engine is described as running rich since the fuel-to-air ratio exceeds what is needed by the bike.

This excess fuel will then leak into the exhaust system and immediately combust due to the oxygen in that compartment. The result is a popping or loud bang from the exhaust system.

Apart from backfiring, another sign of excess fuel in the engine includes a strong fuel smell. You may also notice your spark plugs are charred.

– Low Amount of Fuel

In the same vein, low fuel in the engine is another reason your motorcycle may pop or backfire during acceleration. That is, there’s an insufficient fuel-to-air ratio, which can cause incomplete combustion. A faulty gas pump, filter, or injector could cause this problem.

It can also happen when you change your air filter to a free-moving type. In this case, incomplete combustion will escape through the motorcycle exhaust and backfire.

A common symptom of a motorcycle running lean on fuel is inconsistent power surges. The motorcycle will eventually lose power when left to run on low fuel.

– Ill-fitting Exhaust Header Pipe

Also known as a pipe header, this component collects exhaust gases from the internal combustion engine and moves them to the exhaust system. It allows the engine to work properly, reducing exhaust back pressure. These pipes are made of stainless steel tubings that allow exhaust gas to move without hindrance.

However, they can get slack or loose with regular use. When you have a loose header pipe, your motorcycle will make a popping noise during acceleration. A loosely fitted header pipe can cause an exhaust leak if left unchecked.

– Incompatible Exhaust

If you recently replaced your exhaust system and your motorcycle starts to backfire during acceleration, it indicates a problem with the exhaust. Before replacing your original exhaust with an aftermarket part, you should be sure that all its specifications match your car’s.

If they don’t, your motorcycle may pop or backfire while accelerating. Most aftermarket exhausts need you to reset or remap your ECU. Failure to do this might result in your motorcycle backfiring while on acceleration.

– Faulty Spark Plug

Bad spark plugs lead to intermittent sparks from your motorcycle, especially when accelerating. The spark plug ignites the combustion process for the motorcycle to work.

If these plugs are faulty, they will cause your motorcycle to spark at intervals because the unused fuel finds its way to the exhaust. Over time, the motorcycle will lose complete power.

– Bad Gasoline Pump

A faulty gasoline (fuel) pump is another culprit for a motorcycle that makes a popping sound or backfires. The gasoline pump delivers fuel to your engine from the fuel tank, but corrosion, constant use of corrupted fuel, and clogged filters, among other factors, can damage this pump.

A faulty gasoline pump can cause your engine to run on rich or lean fuel. Whichever is the case, your motorcycle is bound to backfire when on acceleration.

– Leaking Airbox

The airbox collects outside air and feeds it to the intake hoses of most combustion cylinders. An airbox is one of the most common reasons your motorcycle backfires or makes a popping sound. It can start to leak due to cracks from forceful impact and rough riding.

When there’s a leak, it will introduce excess air into the combustion system. In turn, this excess air will find its way to the exhaust system and combust there, causing backfiring while you drive.

– Dirty or Clogged Carburetor

Another common cause of a backfiring motorcycle is a clogged or dirty carburetor. The carburetor supplies your combustion engine with the right air-fuel mixture. Over time, the carburetor can get dirty or clogged due to a buildup of dirt and grime, which will hinder the performance of its needle valves.

In this case, you’ll notice that your engine runs lean or rich more often, leading to frequent backfiring and popping. You’ll also notice that your spark plug appears wet with fuel. Over time, your engine may crank but your motorcycle will refuse to start.

– Dirty Gasoline Filter

A dirty gasoline filter is another culprit that can cause your motorcycle to pop or backfire on acceleration. The gas filter prevents dirt and debris from mixing into the fuel to ensure it runs smoothly in the combustion engine.

If you don’t take out this filter and clean it as often as possible, it can become clogged from dirt buildup. In this case, it won’t spray a fine stream of fuel. Instead, it’ll become inconsistent, affecting the ignition process.

– Clogged Injectors

If you notice your motorcycle backfires on acceleration, you may need to check your injectors. Gasoline injectors work by atomizing fuel pressure from the pump before sending it to the combustion engine. As time goes by, these injectors can become clogged with carbon buildup from the engine and debris.

When this happens, the injectors cannot work as they should, affecting the engine’s performance. Hence, you may notice frequent backfires and popping when your bike is on acceleration.

Solutions to Your Motorcycle Popping or Backfiring on Acceleration

The solutions to your motorcycle popping or backfiring on acceleration include using a fuel gauge and replacing a bad header pipe. You can also try replacing bad plugs and cleaning your gas pump, filter, and injectors. Doing these actions should end the problem.

Take note that a backfire can damage your motorbike, so it would be best to fix it immediately. A backfire occurs when the prescribed fuel-to-air ratio is compromised. When this happens, your motorbike will lose power at intervals and damage your engine in the end.

– Use a Fuel Gauge

A fuel gauge is a measurement tool used to determine the amount of fuel in a fuel tank. When pouring fuel into your motorcycle tank, it’s advisable to use a fuel gauge. That way, you can be certain that your engine won’t run lean or rich and disrupt the combustion process.

Once you can get the right fuel into your tank, it will balance the fuel-to-air ratio. In this case, your motorcycle should be able to speed up without popping or backfiring.

– Replace Faulty Header Pipe

If the header pipe seems to leak, it’s best to replace it as soon as possible. Replacing the header pipe requires precision for proper installation. Hence, we recommend leaving this task to a professional mechanic to avoid damaging other exhaust parts.

Similarly, check for leaks in the manifold and fix them as well. Once the header and manifold pipes work well, it will resolve the problem of popping or backfiring.

– Buy Compatible Exhaust and Remap ECU

Before replacing your old exhaust with an aftermarket part, it’s critical to check that it matches the specifications of your bike. If you’re unsure how to check, you can look at your owner’s manual or manufacturer’s website.

 

You can also consult with a certified mechanic to be sure. If the aftermarket part matches, then ensure you remap your ECU.

You’ll need to alter your computer’s settings to match that of the new exhaust system. Remapping an ECU requires technical expertise, so you should let a certified mechanic handle the process.

– Replace Faulty Spark Plug

One of the quickest solutions to a backfiring motorcycle is to replace the faulty plugs. Before replacing the plugs, you must inspect them first. If they look charred or crooked, you can replace them.

However, if they look clean and white, you don’t need to replace them. You may only need to top up your fuel tank to stop the backfiring.

– Clean or Replace Faulty Gasoline Pump and Filter

To end bike backfires, you can clean your gasoline pump, which is easy to do. It would help if you located it, unscrewed the bolts holding it, and sprayed the pump with a cleaner. Let the spray sit for about 15 minutes before cleaning it off and reinstalling the pump.

If the gasoline pump appears damaged, you should replace it immediately. Following the same process, you can also clean the gasoline filter, which is usually paired with the pump.

– Fix Leaking Airbox

It would help if you also fixed your leaking airbox to prevent fuel leaks and backfiring. Finding the airbox can be tricky, so we recommend taking your motorcycle to an auto repair shop. Without the right tools and technical knowledge, fixing a leaking airbox is challenging and takes a lot of time.

Ensure a professional mechanic carries out the repairs. To check if the installation was successful, fill your tank with fuel and watch your plug. If the plugs don’t appear wet with fuel, your installation of the airbox has been successful.

– Clean Clogged Carburetor

Cleaning a clogged carburetor will also resolve the issue of a motorcycle that pops and backfires on acceleration. To do this, you must locate the carburetor and remove it from its compartment. Take off the carburetor float and spray the carburetor with an automobile cleaner.

Let it soak for about 10 to 15 minutes, and then use a soft microfiber cloth to clean off the filth along with the cleaner. Rinse the carburetor and let it dry thoroughly before reassembling it.

– Clean Injectors

Cleaning a clogged injector is another way to resolve motorbike popping or backfiring. Cleaning the injector is easy. First, you will have to locate it.

Once you find it, spray your cleaner on either side of the injector and let it sit. After that, ensure it looks clean before reinstalling it and other fuel system components.

Frequently Asked Question

– How Can You Stop a Dirt Bike from Backfiring?

You can stop a dirt bike from backfiring by cleaning the gas filters, pump, and injectors. You should also clean your carburetor and ensure your fuel tank contains the right fuel. You should also fix any leak in the exhaust or airbox.

Also, pay close attention to the type of aftermarket exhaust you use as a replacement.

Conclusion

There are many reasons why your motorcycle is popping or backfiring on acceleration.

Here’s a recap of the main points discussed in this article:

• Motorcycles popping or backfiring on acceleration is a problem that most bike owners ask due to a malfunction in the combustion engine.
• The main causes of backfiring and popping in motorcycles are an improper fuel-to-air ratio and a clogged carburetor.
• A dirty gasoline pump, filter, injector, and a damaged header pipe can also cause this problem.
• You can fix the issue by using a fuel gauge and by cleaning the gas pump, filter, and injectors.
• You should also clean your carburetor and fix all possible leaks in the manifold or in the airbox.

With this useful resource, you can now eliminate the problem of backfiring or popping whenever your motorcycle is in acceleration.