How long does it take for the gas to stop working in a motorcycle?

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Most of us know what gas is and how it’s used. But there are less people who know about the properties of gas and it’s shelf life. Many people may believe that because gas has been in existence for thousands of year, it will be just as durable above ground.

The gasoline we see and use is much different than the gas that’s under ground because what we use is refined. Gas does have a shelf-life, despite what you may think. You may be planning to store your motorcycle for a while, or you just don’t ride it enough to use a full tank of gas all that often and wonder if that gas inside will eventually expire.

What is the average time it takes for gasoline to go bad on a motorcycle? A motorcycle with unstabilized gas may start to go bad within 30 days, especially if it isn’t being used. Exposure to oxygen eventually alters the gas’ chemistry, which can cause gum and varnish deposits. If gas has been stored for more than six months, it should be thrown away. After 6-12 months, stabilized gas should not again be used.

The staple of society, gasoline has been essential for human survival. If it isn’t treated properly, it can lead to a lot of problems later on. Taking the proper steps in caring for the gasoline you use can prolong it’s shelf life as well as keep you riding your motorcycle without a problem.

Why Motorcycle gas goes bad

Oil is a black liquid that rises from the ground. This image is a result of how movies depict oil being discovered.

However, as you might have noticed, the gasoline that you put in your motorcycle doesn’t look like the black stuff in the ground. That’s because the black stuff in the ground is still considered crude oil, or “unprocessed oil.”

This oil is refined and processed by oil refineries, which then gives us the gas that we use every day in our bikes. When the gas meets their specifications, the refineries ship it to gas stations. You can usually get the gasoline from the station in a matter of days.

A characteristic gas has is called volatility which means it vaporizes at an efficient rate that’s beneficial for your motorcycle engine. But because of it’s vaporizing characteristic, that means it will continue to do so whether or not the engine is using it. This means that over time the gas’s ability to combust will weaken.

Exposure to oxygen over time can alter the chemical composition of the gas. In addition to the gas vaporizing, it also forms gum and varnish deposits from the oxygen mixture.

Condensation can build up in fuel tanks as well. This can cause a water-water mixture in the fuel. Motorcyclists should be aware of this because ethanol gas is essentially water attractant. It can also increase the moisture content in the fuel system.

The change in the chemistry of gasoline can happen quickly, especially if you are not using it or aren’t topping off your tank with fresh gas. After filling your tank with gas, the chemical reactions can begin within 30 days. They will continue for a period of time.

What Bad Gas Does to Your Motorcycle

Now that we’ve discussed the technical part of gasoline and it’s chemistry, you may be wondering how using bad gas can influence your motorcycle. Perhaps you’re planning on storing your motorcycle for the winter or for a long period time (see my guide here for long term storage), or maybe you only use your motorcycle occasionally that doesn’t require routine fill-ups.

It is a fact that using old or bad gas on your motorcycle can cause serious damage to your machine. Gas will eventually form varnish and gum deposits, which will cause it to gel up. Consider all the lines, valves, and jets that liquid gas must travel to power your engine. Then imagine gel running along those lines.

Old gas can clog up your fuel system and cause major damage to your bike. Also, gel gas takes a lot longer to burn than liquid gas so your motorcycle’s performance will suffer.

If you don’t treat it soon, your motorcycle won’t be able start or run for long. Your motorcycle will become unusable because of the blockage in fuel lines.

How to Care for a Motorcycle with Bad Gas in It

If you’ve become a victim of having old gas in your motorcycle and have noticed your motorcycle not running well or not running at all, know that you haven’t completely ruined your machine.

It is possible to get rid of all the junk and make your bike look like new. You must be willing to spend a bit of time doing it though, because cleaning out your fuel system isn’t going to be just an hour long project.

You will need to remove the carburetor completely from your motorcycle before you can rebuild it. You will need to take everything apart and clean it thoroughly, using an ultrasonic cleaner if possible. You’ll need to pay special attention to the jets and make sure they’re clear of debris.

You’ll probably need to replace all the fuel lines throughout your motorcycle. Those are inexpensive and shouldn’t take long to replace. Consider placing a fuel filter in your fuel line if you don’t already have one.

If you have a fuel injector, you’ll need to clean that as well. Although cleaning them is a bit more difficult than cleaning a carburetor they are easy to clean with some fuel injector cleaners.

As soon as possible, empty the gas tank. It should be easy to empty the tank by disconnecting the pipe from the petcock. Then turn the petcock on. To catch any gas that is left behind, make sure you have a container under the petcock.

Once you have assembled everything back together, you’re ready to add some fresh, new gas. You’ll probably still have some deposits throughout the system from the old gas circulating with the new gas, but hopefully your fuel filter can catch that. After doing this, you may have to change your fuel filter slightly sooner than usual.

How to Prevent Bad Gas from Causing Problems

Whether you’ve had to go through the endeavor of cleaning out old gas from your motorcycle, or you simply don’t want to experience such horror, there are a few preventative steps you can take to keep the fuel system in check and unclogged with bad gas.

Stabilizers are essential if you intend to leave your motorcycle sitting for some time. A fuel stabilizer can protect the gasoline in your motorcycle. It bonds to the gas it is mixed with, and prevents the gas from rapidly vaporizing. It slows down the chemical reaction that gas undergoes to oxygen.

Add fuel stabilizer to your motorcycle. Make sure that you turn it on for a while so the stabilizer has a chance to circulate throughout the fuel system. Stabilized gas should be used no later than 6-12 months, as the inevitable chemical reactions that gas will undergo after this time are still possible.

It is best to completely empty your gas tank and fuel system if you plan on storing your motorcycle for a long time, such as several years. While this may reduce the possibility of condensation building up, it is still better than letting old gas sit in there.

Similar Questions

What happens to gas in recreational vehicles that are not fueled by gasoline? No matter the vehicle, gas’s properties and chemistry are the same. Old gas in vehicles, such as cars, four-wheelers, snowmobiles, or cars, can lead to the same problems as motorcycles.

Do engine oils ever go bad? Oil can also go rancid, much like gasoline. Once oil is opened from a sealed container and placed inside an engine, it can start going bad after a few months and shouldn’t be used longer than 6 months. A sealed container can keep oil for several years, but its shelf life is longer.

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