Why Is My Go-Kart Backfiring? 4 Simple Fixes!

When your go-kart backfires, the combustion of the air-fuel mixture happens outside of the cylinders. When a backfire occurs, you may experience power loss and poor fuel economy from the engine.

In worst case scenarios, it can even damage your exhaust system. Therefore, you should try to fix backfires as soon as you identify them. In this guide, I’ll be taking you through the reasons why your go-kart is backfiring and how you can easily fix this. 

Here’s a quick overview of the topics I’ll cover:

What Is a Backfire on a Go-Kart?

The engine on your go-kart requires air, fuel and a spark to start the combustion cycle. To ensure that your engine runs continuously, the fuel and air-fuel ratio needs to be optimal. 

When air and fuel are inducted into the cylinder the spark from the spark plug ignites the mixture, which combusts and moves the pistons. A backfire can occur if the air-fuel mixture combusts outside of the cylinders. ‘

Pro Tip: If your go-kart backfires, you’ll commonly hear a rambling or a popping sound. That’s a sign that you should immediately fix it!

What Causes Go-Kart Backfires 

There are various reasons why go-karts can backfire. Most of the time it’s due to an incorrect fuel mixture – either too much air or fuel. It may also be due to blockages in jets or intakes on your carburetor. Here are some of the most common reasons:

  • Fuel is too lean or too rich
  • Faulty ignition/spark plug
  • Low fuel pressure
  • Blocked air flow

How to Fix Backfires on a Go-Kart?

Fixing this issue is easy if you know what and where the problem is. But don’t worry, I’ll guide you through it. Below you’ll find the 4 best ways to fix a go-kart engine that’s backfiring.

1. Clean Carburetor 

As has been highlighted earlier, go-kart engines require air and fuel, in order to start the combustion cycle in the cylinder. Your go-kart carburetor ensures that the right mixture is inducted into the engine. 

When the jets on your carb are blocked or debris are trapped in the float bowl, it may not be able to ensure an optimal air-fuel ratio. If that’s the case, proceed to my guide on how to clean a go-kart carburetor, as you’ll need to clean it thoroughly.

There, you’ll need to ensure that you clean all of the internal components properly, such as the jets, screws, pins, needles and the float bowl. You should also consider using a carb cleaner while you’re at it. 

2. Unclog Air Filters

Go-kart backfiring can also happen if the fuel mixture doesn’t have enough air. The carburetor on your go-kart is connected to an intake manifold, which leads to the air filter. When the air filter is clogged, not enough air enters into the carburetor to mix with the fuel. 

Once that happens, the fuel mixture is too rich (too much fuel in the mixture, compared to air). One way to ensure that enough air is entering the carburetor is to clean the air filter and the intake manifold. 

Here’s how you can do this in a few simple steps:

  • Remove the bolts/camps from the intake manifold and air filter
  • Remove both the intake manifold and air filter
  • Clean the intake manifold
  • Clean the air filter (you can also use an Air Filter Cleaner to restore its condition)
  • Reinstall all of the components

3. Check Fuel Filter, Pipes & Mixture

Go-karts also require the right amounts of fuel. Therefore, it’s important to check if the fuel filter and the fuel pipes are clogged or leaking. Ensure that the fuel tank supplies the carburetor the correct amounts of fuel.

If you’re running a two-stroke engine, you’ll also want to ensure that your go-kart is running the right mixture. Check out my go-kart fuel mixture chart to find out more.

4. Change Spark Plugs

Another reason that could cause your go-kart to backfire is when the spark plug doesn’t provide the spark at the right time or sometimes not even at all. There are two things that you’ll need to check here.

Firstly, ensure that your spark plug isn’t faulty or worn out. If that’s the case, you should replace it with a new spark plug that is suitable for your go-kart. 

Secondly, inspect your spark plug and ensure that it’s screwed in correctly. It’s important that the spark plug gap is optimal. You can ensure this by twisting the spark plug until it’s firm and secure. 

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About Gerrit

Owner, Researcher, Writer & Editor at GoKartGuide.com

Hi, I'm Gerrit. I have been racing go-karts competitively and recreationally for the past 20 years. Apart from actively growing local karting communities, I run GoKartGuide and write comprehensive articles, guides & reviews about go-kart racing. I race, build, mod, & discuss go-karts whenever I find the time. Thanks for stopping by and enjoy the read!

My goal with this site is to share valuable go-kart racing information through guides, articles, reviews, track details and more.

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