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Why Does My Motorcycle Backfire? (With 5 Tips)

Why Does My Motorcycle Backfire? (With 5 Tips)

Many people have this problem with their engine with motorcycle backfire. It's a scary sound when you kick on your bike and hear a loud popping noise! It's that sudden burst of fear, that startles you and everyone around.

Backfiring on a motorcycle engine is due to an emission system malfunction, in which there is too much air or fuel present. This results in an incomplete combustion where the fuel is ignited by the heat of the exhaust.

This explosion is supposed to happen inside the combustion chamber. When it doesn't, the engine has an interruption. This causes the backfire explosion to occur in the intake or exhaust, both resulting in the loud sound. In some cases the exhaust also spits out a partial flame. Not only that, it can even give a jolt to the rider on the bike. 

Is backfire bad for your motorcycle?

How big or bad the backfire is, is usually based on how loud the combustion sound is. Most often it's only a mild cough like sound, and that's usually not too bad for your engine. However, this will get worse and stronger over time.

If unaddressed, backfire could cause severe damage to the engine's exhaust. At that point you could be looking at more expensive repairs and higher costs.

This is definitely a problem you'll want to fix before riding the motorcycle anymore. Yet, you'll be glad to know that it's typically a quick fix when checking the right parts. There's a few key factors that contribute to what causes a motorcycle to backfire in the first place.

What causes motorcycle backfire?

When the engine on your motorcycle has an emission system malfunction, this is due to the engine running rich or lean, which in turn causes backfire.

If there is too much fuel than air in the engine, this is known as running rich.

If there is too much air than fuel in the engine, this is known as running lean.

Now that we've identified why this happens, it can be caused by a multitude of different sources. The best way to fix your motorcycle backfire is to test the engine.

How to test and fix your motorcycle engine

To test your engine and troubleshoot the problem, you'll want to first park it in a garage or location where you can work on it. A few tools you may need include:

  • T-Handle wrench
  • Screwdriver
  • Plug wrench
  • Wire pliers
  • Torque wrench

The two most common problem areas to check are your jets and carburetor. It's typical for these areas to get dirty and clogged with debris.

Using carburetor cleaner spray should do the trick, along with a towel or other cleaning supplies if it's really dirty inside the part. Make sure to give each part a thorough clean before reassembling your motorcycle.

The following YouTube video shows how to tune and fix motorcycle backfire:

Tips to prevent motorcycle backfire

There's a few key things you can do to keep your motorcycle's engine from backfiring. Each of these tips vary from maintaining certain parts, or adding certain fluids. Be sure to keep your owner's manual handy when taking apart your bike.

#1 - Keep your air filter clean

This is something you'll want to do on a regular basis. A clogged air filter will impact your engine's ability to take in new air. This is important for proper engine function. If you prefer to ride in the mud, you'll also want to check this more often.

#2 - Keep your carburetor clean

One of the most common problems that leads to motorcycle backfire is the carburetor. Keep this clean with a high grade carburetor cleaner spray. If it's too dirty, fuel will not flow correct to the engine causing it to run lean.

#3 - Keep your jets clean

Jets are also a part that can tend to get quite dirty. If clogged, it will prevent fuel from getting to the engine causing it to run lean.

#4 - Change fuel grade

Going for a higher fuel grade works well to mix in every now and then. You don't always need to do this, yet it can help to reduce the buildup of additives in gasoline. In addition, it will keep your fuel tank cleaner. Be sure to check your owner's manual to verify restrictions or recommendations for your specific model.

#5 - Use fuel injector cleaner

If your motorcycle is fuel injected, utilizing a high grade cleaner will clean out debris and gunk that builds up on the fuel lines. This isn't something that needs to be done too often, and is more precautionary.

To Conclude

By following these tips you'll be to keep your motorcycle from backfiring on you. As you can see many of the problems come from having a dirty bike.

The best method for prevention is to check these areas on a regular basis and keep the parts clean. A bit of routine cleaning can go a long way on keeping your motorcycle in good shape and functioning well. Not to mention, this will extend the lifespan of your bike and cut down on other more expensive repair costs.

Good luck, and happy riding!