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Riding a bike is always a rewarding experience for bike lovers. This is at a time very much exciting and thrilling experience that one can enjoy. The bike is now the new age transpiration option, which is very convenient to move one place to another.
Purchasing a bike is a big investment and you always need to keep it in tip-top position to make it last longer. But if you don’t know the right method of bike maintenance, your bike can backfire suddenly.
There are many people, who love to enjoy the adrenaline-rushing huge sound of the bike but there is a great possibility on the exhaust backfire. This is a frightening experience for the bike riders. If the bike backfires, there should a problem in the mechanics of your bike’s engine.
If your bike backfires, you need to find out the actual reason for it that why does my dirt bike backfire? If you know the reason, it will be much easier for you to rectify the problem with your bike. You can try it by yourself or can consult a mechanic to resolve the issue of bike backfire.
Table of Contents
What Causes Backfire?
Generally, an explosion in the bike’s combustion chamber can cause backfire. In the exhaust and intake of your bike, an explosion occurs usually. If the dirt bike backfires when kickstarting, you will find a bad, loud noise coming from the bike.
- Even if there anything wrong in your bike’s emission system, backfire can occur. Check out some reason for bike backfire:
- Backfire can happen if there any leak in the exhaust
- If there any type of leak in the exhaust, backfire can happen anytime
- Another reason for backfire can be incomplete combustion that occurs usually because of the high level of fuel in the bike’s engine or if there more air
- Sometimes the ratio of air-to-air becomes quite unbalanced as you change the exhaust pipe. This can be the reason of backfire also.
- The design of the pipe can be another reason for backfire as it causes huge airflow in your bike that increases gradually and it can cause backfire.
- Other reasons for backfire can be clogged filter of the bike, weaker fuel pumps, etc.
- If there any emission system stops working or if there any malfunction, backfire can occur. There can be reasons like an engine running lean or rich. Engine running rich means there more fuel than air in the engine. A lean engine means there are less fuel and more fuel in the engine.
There are many reasons for bike backfire but you need to identify it first to prevent it. But you need to go for an engine test first to avoid bike backfire. Dirt bike backfiring on acceleration can be a reason of imbalanced air-fuel ratio in the engine.
Why does my bike backfire on deceleration?

Many of the people come up with the thought that bike backfires occur usually on the decoration due to some issues with its engine or fuel. Dirt bike backfires on deceleration is a very common issue that the bikers often face. But backfire occurs most of the time because of unburnt fuel ignition or air ignition in the bike’s exhaust. The fresh air that enters the exhaust makes it hot and makes the un-burnt fuel burning. It causes backfire.
Sometimes, bike backfire occurs if the tappets of the bike are tight or the valves are a leak. To reduce the chances of this, you need to ensure that there is no presence of an exhaust leak. You need to check it first if find the issue; you need to alter your fuel curve at the closed throttle.
You need to sync also the position of the throttle. It will help you in check the reads the accelerometer read 0 as your bike is in rest. If the dirt bike won’t idle and backfires, there must be an issue in the engine.
5 Tips to Prevent Your Dirt Bikes Backfire [Tested]
You can prevent bike backfire in different ways.
#1 – Keep your carburetor clean
To start the process, you need to check the carburetor to find out whether it is clean or not. A dirty carburetor can stop the fuel to pass through properly. It can cause backfire also.
#2- Keep your jets clean
You need to check the jets also. If you find too much debris in it, again the fuel will never be able to properly pass through the bike’s engine. In case, the engine will run lean and it can cause backfire.
To prevent backfire, you need to ensure that the jets and carburetor of your bike are completely clean and there is no debris present there. You need to bring your bike to a skilled technician or mechanic often to clean it up.
#3- Keep your fuel line clean
You need to clean up properly all the dirt that trapped in the bike’s fuel line. For the purpose, you can use a high-quality cleaner. For cleaning, you can consider checking the manual guide given by the manufacturer or can take it to the mechanic.
#4- Change fuel grade
Avoid using the low grade, low-quality fuel. It can be a significant treason of bike backfire as it causes clogged fuel lines. To keep the fuel line clean, you need to use only the high-quality fuel to avoid backfire.
If the line is clean fuel can easily pass through the bike’s engine and there will be no imbalance of air-fuel inside the engine to cause backfire.
#5- Keep clean your bike regularly
As you ride the bike through the touch and rough road, it can pick up grime and dirt easily. You need to go for regular maintenance of your bike. Clean up the different parts of your bike and surely the engine.
If the dirt builds up inside the engine, it can backfire. Make sure that there is less air inside the bike’s engine as the fuel can efficiently pass through.
By keeping in all these things in mind, you can avoid bike backfire surely. To clean your dirt bikes properly, you may read this in-depth post here.
Is Backfire Bad for Your Dirt Bike?
Backfiring is certainly not a good thing for your bike but it usually depends on the type of backfire. How bad or huge the bike backfires is based usually on the combustion sound. If it is cough like a simple sound, this is not that bad for the bike’s engine. But it can be alarming for you because it will get stronger and worse over time.
You need to address even the simple odd sound to prevent further damage. If it is unaddressed, the backfire of the bike can cause many types of damage to the exhaust and engine. It needs to pay more to repair the issue or maybe an engine change.
This is a big problem that you need to fix on the right time. If you check the parts of your bike properly to find out the problem and it will be easy to fix them. Backfire can be bad for your bike if it is big and not addressed.
Can a backfire damage an engine?
If it is loud sound and the actual backfire of your bike, it can damage your engine. But if it is just the “after hire” it will never damage the engine so much and can be fixed easily.
If you don’t take your bike to the mechanic after having an after a fire or just a small or cough like sound, it can cause severe damage in different parts of your engine and in the end, you may need to replace the engine of your car. Even with regular maintenance and checking of your bike, you can avoid the issue easily.
What are the symptoms of a bad carburetor?
A carburetor is a device that mixes air and fuel in a combustion engine.
Carburetors are still found in older cars or bikes. Today the carburetor is outdated and most of the vehicles made after 1990 use an electronically controlled fuel injection device instead of the carburetor.
My Favourite Carburetor-
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But you have a choke on your vehicle it almost certainly is carbureted and not an injection. But how to know if your carburetor is bad or failing:
Reduced performance of the engine
One of the common symptoms of bad or a failing carburetor is surely the reduced performance of the engine. The carburetor of a car is the key component that causes delivering and metering the mixture of air-fuel the need to run you’re the engine properly.
So, if there any problem, it may throw off the oil-air mixture and also reduce the performance of the engine. A bad quality carburetor may cause the sluggish acceleration of the engine and so the reduction in fuel efficiency and power.
Black smoke coming out from the exhaust
Another symptom the associated commonly with a bad carburetor is sure if you find that black smoke is coming out from your bike’s exhaust. This is just the indicator that shows that the engine of your bike is running very rich and eating a lot of fuel.
If the carburetor is causing an excessive amount of fuel and producing the black smoke that means the carburetor is producing excessive emission.
Overheating or backfiring
Engine overheating or backfiring is other issues associated with a bad carburetor. If the carburetor of your bike has a severe issue, it will deliver the lean mixture. Lean mixture means the fuel-air mixture has less fuel than air.
It can cause overheating or backfiring. Having a lean mixture is also quite bad for the performance of your engine and it can damage the engine also.
Hard starting
This is another symptom that associated commonly with failing or bad carburetor. The ratio of air-fuel in the engine is responsible for metering and blending and having the right ratio is important. This ratio is essential and the utmost sensitive during the cold starts.
A problematic carburetor can affect the ratio of air-fuel and it may cause hard starting of the bike. Depending on the type of the issue, your bike will be tough to start when it is warmed up. These are just a few symptoms that may help you to understand that there may be some issues with your carburetor.
What causes spitting back through carburetor?
If your bike is backfiring, you need to ensure whether is backfiring just because of the exhaust or it is spitting back through the carburetor. The backfiring of an engine through the carburetor is known popularly as coughing or spitting. This type of spitting usually caused by the sparking in the spark plug as it is not turned on and also there is an open valve in the exhaust.
If the mixture of air-fuel is too much rich in your engine and there is unburned fuel in the exhaust of your bike, backfiring or cross firing can occur from the one sparking wire of plug to other parts as they touch each other. If a valve of the exhaust is open, it can cause a big issue.
Getting a late or retarded timing can make your engine to run quite rich. As the valve is open and the mixture is not burning, it can ignite the unburned fuel in your exhaust system.
Crack distributor cap can cause the spitting issue also. If it has carbon tracking that causes cross firing between different terminals, it may send the spark to the sparking plug and causes backfire.
Spitting through carburetor occurs in the morning mostly when there is the lean air0fuel mixture. As the accelerator pump in the carburetor is not squatting fuel properly before the time when the key jets of the bike start working, spitting can occur.
When a bike comes in spitting and coughing with the ignition problem, a coil might be shot, a plug fouled, and this happens a lot, the guy might have gotten a little too fancy trying to hide new plug wires but actually caused his problem by letting those wires rub up against something or get pinched and broken.
Final verdict
Dirt bike backfires but won’t start or other associated issues are quite common that faced by the bikers. It can be fixed up easily if you are aware of the issue and follow a regular maintenance routine of your bike. If you are thinking that why does my dirt bike backfire, you need to go for a test or complete check. Testing and checking can be done with a professional mechanic only.
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