Why Your Quad Keeps Cutting Out and What To Do

Having a quad bike that keeps cutting out without any clear indication of why can be very frustrating, especially if it gets in the way of your fun. In my experience, and probably in most cases, it is easy enough to diagnose the reason why this is happening and easy enough to get it fixed as well.

There are many possible reasons why a quad bike can be cutting out, which include possible dirt in the carburetor or the carburetor being clogged, water in the fuel, and less common cases, problems with the fuel valves and fuel lines of the quad bike.

Let’s examine in a bit more detail and try to get your quad bike sorted if you are experiencing this issue.

If your quad cuts out once or twice and doesn’t happen too frequently, it might not be all that bad. When your quad starts cutting out more frequently, it can be extremely frustrating, especially when you are riding with friends or trying to beat your best time on a trail. If your quad cuts out while you are trying to overcome an obstacle, it can become dangerous.

If this has been happening to you, don’t worry, you have come to the right place. In this article, we are going to look at some possible reasons why your quad keeps cutting out and what you can do to solve the problem.

Whether your quad is a two-stroke or a four-stroke, the causes and solutions will be similar for both.

Carburetor

When a quad keeps cutting out, one of the most common reasons is because the carburetor is either dirty, you have dirty fuel, water has mixed with your fuel, your carburetor is clogged, or your carburetor is damaged. Let us hope that it is not the last one.

Let us take a look at how your carburetor can pick up some of the problems listed above.

Dirt in your carburetor

Dirt in your carburetor often comes from the gas tank and mostly happens when you run the quad with very little fuel or run out of fuel. The dirt from your gas tank will get sucked in the carburetor. This also ties in with dirty fuel. A dirty carburetor is also a sign that your air filter might be faulty, so you might want to check that out as well.

If your air filter is is a problem, I recommend replacing it as the part is inexpensive. Getting to the air filter is fairly easy. In most cases, remove your seat and you will see the airbox lid. The airbox lid should just pop off without using any tools.

Once you have the airbox lid off, you will have access to the air filter. Use a Philips head screwdriver to loosen the clamp and remove the filter from the quad. Remove the frame from the filter and then inspect the filter you want to make sure that filter is in good condition.

If the filter is in good condition then you can just clean it out, use air filter cleaner and air filter foam. Please do not use any other chemicals. Make sure the filter is completely dry before placing it back into the quad, it is best to leave it to dry overnight.

Water in your fuel

Water in your fuel is more often than not, a result of storing your quad outside with no cover. I always recommend storing your quad in a garage or at least use a cover if storing it outside. Having to always cover up the quad after use might seem a little tedious, especially if you are tired from riding all day, but it saves a lot of time and money on maintenance.

Carburetor is clogged

This is pretty self-explanatory. Dirt, rust, and dust from your gas tank can either clog your carburetor and/or clog your main and idle jets.

How do you get to the carburetor to check why it is giving you problems?

In most cases, you will not have to remove any panels of the body to do this.

  1. Make sure your fuel valve is off and then disconnect the fuel line from your carburetor.
  2. Disconnect any electronics that have anything to do with the carburetor, such as the electric choke, if your quad has one.
  3. You want to disconnect the throttle cable from the carburetor. Make sure you loosen the throttle cable a little bit before disconnecting it from the carburetor.
  4. Loosen the air filter clamp and the clamp that holds the intake boot on your carburetor.
  5. Once you have disconnected all necessary components, you should be able to disconnect the carburetor from the engine. Do not be afraid to give it a few wiggles to get it loose.
  6. With the carburetor disconnected from the engine, you should be able to inspect it. I recommend using clear glass to dump excess fuel out of the carburetor. look at the fuel in a well-lit environment to see if your fuel has any water or dirt in it.

Please remember that when you open the carburetor, some parts are delicate and you should take care when handling the inner components. Now that you have it open, inspect the carburetor for any problems that I listed above.

If your Carburetor has dirty fuel or fuel mixed with water, I recommend cleaning the carburetor and draining all the fuel from your gas tank and then use compressed air to clear the tank of any rust or dirt particles. You then want to replace the fuel filter.

If any of the jets in your carburetor is clogged at all, you want to use compressed air to get rid of as much gunk as possible. Remember that the jets are often made of brass so you want to take extra care when handling them.

Check your fuel valves and fuel lines

Okay so you have inspected the carburetor and found no problems, or you fixed any issues it had. Now you want to check your fuel valves and fuel lines.

It is very unlikely that you would even be able to start the quad if there was a problem with the fuel valves or fuel lines, but you could check them just to be safe.

Look for any leaks, kinks or, breaks and replace anything that looks suspicious.

You also want to look for any type of gunk that is building up. Once again, this is very unlikely if you are able to start the quad, but it is best to check because maybe it is restricting the amount of fuel getting to the carburetor.

Conclusion

If your bike is able to start but keeps cutting out, the problem is narrowed down to the carburetor. In the article, we have explained how to disconnect the carburetor from the engine and what to look out for.

If you are unsure about working on your quad, it’s better to take it to a professional.

Happy quad biking!