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10 Reasons Why Your Dirt Bike Battery Is Going Dead

Keeping your motorcycle battery in good condition is key if you don’t want it to die. Like many parts of a bike, motorcycle batteries require proper maintenance, or they won’t last very long. There are a few key reasons your dirt bike battery might be going dead that you should be aware of.

The 10 reasons your dirt bike battery is going dead are:

  1. You’re overloading the battery
  2. A problem with the voltage regulator
  3. The battery is old
  4. Working conditions are too hot
  5. You’re riding in cold weather
  6. A short circuit in the electrical system
  7. Battery sulfation
  8. Too much vibration
  9. Poor ground connection
  10. Using a faulty charger

Below, we’ll go over each of these reasons in more detail, discussing why they’re leading to a dead battery. Once we’ve gone through the key reasons your dirt bike battery is dying, we’ll give you some tips to get the most out of your dirt bike battery.

10 Reasons Your Dirt Bike Battery Is Dying

1. You’re Overloading The Battery

Overloading the battery is the most common reason for dirt bike batteries dying. This is especially true if you have too many accessories, as the battery might not be able to provide the required power for all of them and the basic operations of the bike itself. If this is the case, you should remove some of your accessories, or buy a more powerful alternator.

While the engine is running and all of the accessories are on, you should check the voltage with a voltage reader. If it shows less than 13.8 volts, the battery might not be able to handle all the accessories. Consider which you really need, and get rid of any you don’t need so you don’t overload your dirt bike battery.

2. A Problem With The Voltage Regulator

This problem is more common with older bikes or bikes with high mileage on them. If the voltage regulator or alternator is faulty, it will directly reduce the lifespan of the battery. You should regularly check all the connections to make sure that they are in a good condition.

The voltage regulators that come with most bikes usually don’t last long and require replacement sooner or later. In order to get the most out of your regulator, perform these checks regularly.

3. The Battery Is Old

Dirt bike batteries usually don’t last terribly long as they are, so if your battery is more than 5 years old, you might need to replace it purely due to its age. How long your dirt bike battery lasts will depend both on how well you take care of it, and how often (and aggressively) you ride.

If the battery isn’t working, you should perform a test with a voltage reader. Turn on the engine and test the battery with all the lights on. It should read at least 12 volts, with 13-14 volts being optimal. If it reads much less than this, your dirt bike battery might be about to die.

4. Working Conditions Are Too Hot

Too much heat can cause a lot of damage to your dirt bike battery over time. If your battery works under hot conditions most of the time, it might burst and spark, and eventually burn your bike. This can be especially dangerous if it happens while you’re riding.

You should keep the battery away from heat as much as possible. It’s especially important during summer since many people put the battery at the top of the bike. Doing this can allow it to accumulate too much heat and get severely damaged. If you live in a hot area that gets a lot of sun, you should also consider packing the battery in a heat shield.

5. You’re Riding In Cold Weather

While too much heat can damage your dirt bike’s battery, riding in cold weather can also damage the battery. During winter, you should part your bike in the garage, since it can die in a single night if you leave it outside.

Make sure to keep the battery fully charged during the winter. Most batteries can endure cold weather better if they’re fully charged. If you leave it empty, it will die or get seriously damaged in a matter of days.

6. A Short Circuit In The Electrical System

A short circuit in the electrical system is quite a common problem with motorcycle batteries. The electrical system itself is complicated and can be quite dangerous to repair on your own. In case of a short circuit, you should always call a technician who knows how to deal with it properly.

Before you call, make sure to check for any broken parts, such as bad connectors, or anything that looks disconnected. Sometimes, the main fuse might cause a short circuit and damage all the electrical components. In that case, you would need to simply replace it. It’s not worth trying to ride a bike with a faulty electrical system, so always take it to a professional.

7. Battery Sulfation

If you have a lithium-sulfur battery, you might run into the problem of sulfation. If you check it with a voltage reader and it shows a voltage lower than 12 volts, it means that the battery is probably sulfated.

Sulfation usually prevents a battery from accepting a charge too. Essentially, if the battery is fully drained, sulfur from the battery can stick to the metal plates inside it. This blocks any current flow, and it can eventually corrode the metal plates. As long as the plates aren’t too corroded, you can get this repaired without too much of a cost.

8. Too Much Vibration

Even if you maintain your dirt bike’s battery properly, too much vibration can cause irreparable damage. Certain types of dirt bike battery are better able to handle vibration than other types, so it’s important to bear this in mind when buying a dirt bike battery too.

If you often ride off-road, you might consider buying an AGM or gel battery. They can endure much more vibration, and generally, they last much longer than conventional batteries. However, they can also cost a bit more, so it really depends on your priorities as a rider.

9. Poor Ground Connection

If your dirt bike battery is often going dead, there might be a poor ground connection between the frame and the battery. This can prevent proper charging, which will eventually cause damage over time.

The first thing you should do if you think this might be the case is to carefully check all the connections on your bike. If everything is connected up but the battery is still dying, disconnect the battery and give the connections a clean with some sandpaper and see if that resolves the problem.

10. Using A Faulty Charger

Although it’s not a common problem, a faulty charger can also cause your battery to die sooner than it should. It’s important to check the cable and ensure that there are no issues with the capacitor. Also, check if there are any cracks that might damage the charging lead itself.

If the problem is in the charging capacitor, you will need to replace it with a new one. One tip to get the most out of your dirt bike battery is to always charge it until it’s full. This way, you don’t run the risk of it losing capacity over time.

How To Choose The Right Battery For Your Dirt Bike

One of the reasons your dirt bike battery might be dying quickly might be that you don’t have the right battery for your bike. This can even be influenced by your riding style, so let’s take a look at what to consider when buying your next dirt bike battery.

Power Rating

You should always take note of the technical details when buying a dirt bike battery. Most batteries provide 12 volts, but for smaller bikes, you might need a battery with less power. Still, if you buy a battery with a higher power rating, it won’t do any harm as long as the model is compatible. It’s more important to ensure you have enough power for your specific bike.

Battery Life

Battery life is measured in cycles, and most batteries promise a lifetime of between 600 and 1,200 cycles. If you buy a battery with an extended lifespan, you will spend less time and money on replacements, so it might be better to go for a more expensive battery at first so you can save money in the long run.

Your Trip Length

If you often drive through the city or take short trips on your bike, you should buy a battery that doesn’t need to be recharged often. This is because, on short distances, the alternator won’t charge your battery for very long. This means you run the risk of trying to start your bike with a dead battery, unless you remember to charge it in between trips.

Consider The Climate

If you live in a hot area with a high humidity level, you should buy a battery with an extended lifespan. Batteries with a higher cycle rating are able to withstand hot weather better than a battery with 500 cycles or less.

How To Maintain Your Dirt Bike Battery

Many motorcycle owners don’t know how to maintain their batteries properly, and fewer understand how their battery actually works. Although it’s not a really complicated process, there are a few things that you should know about dirt bike batteries so you can get the most out of yours.

Battery Myths

Most people think batteries store electricity, but that’s a myth. They actually contain electrolyte and plate materials that produce electricity due to the chemical reactions they undergo. That causes the battery to discharge, and, in the case of lead-acid batteries, forms lead sulfate on the metal plates.

As the battery charges, all these reactions work in reverse. However, if the electrolyte fluid levels are not maintained, the battery will lose its capacity and efficiency, and the changes to the metal plates will become permanent. This drastically shortens the lifespan of the battery.

Check The Electrolyte Levels

If you own a lead-acid battery, you should therefore regularly maintain the electrolyte levels to ensure the battery can charge and discharge effectively. You should check the electrolyte levels every month and top them up with demineralized water if required. You shouldn’t need to add any acid at any point.

Keep Your Bike Under Cover

As we mentioned earlier, exposure to too much heat can cause your battery to die very quickly. If it’s the summertime and is very hot, make sure your bike isn’t exposed to direct sunlight for too long, since it will heat the battery and eventually cause irreparable damage if left long enough.

You should also cover your bike when it’s cold, and ideally keep it indoors if you have a garage. If it’s -18o, your battery won’t be able to deliver constant current for more than 30 seconds. If your battery is old, it will be even less powerful in the cold.

When the engine is cold, it becomes harder to crank, which requires the battery to work harder to get it going. Also, it directly affects the battery’s ability to supply the current required for cranking. So, be sure to keep the bike covered in both hot and cold weather.

Clean The Battery Regularly

Even when not being used, batteries have a natural tendency to discharge over time, even if very slowly.Batteries can easily drain due to the buildup of dust combined with humidity. So, you should regularly wipe any dust or dirt off your battery to prevent it from draining faster than it should.

If the battery is not regularly kept clean, you might need to clean it with a mixture of baking soda or water. However, if maintained properly, you can simply clean it with a piece of cloth.

Clean The Terminals

The accumulation of acid and sulfate can damage battery terminals and reduce their contact area. It will prevent the battery from charging to its maximum and will also prevent it from supplying enough current.

If that happens, terminals will overheat and cause even more damage to your bike. Because of the poor contacts, there will be a buildup of electrical resistance, which will make the engine difficult or impossible to start.

Depending on their condition, you might need to remove the terminals and clean them with a wire brush. Once finished, rinse them with water and add a little bit of Vaseline to prevent corrosion.

Important Safety Advice

Maintaining the battery can be dangerous if you don’t pay attention to basic safety protocols. The acid inside a battery is highly corrosive, so you should avoid spilling it on your skin, eyes, clothing, or even metal surfaces. You should always wear gloves and proper eye protection.

Make sure not to wear any jewelry or rings while working on the battery, since it might create a short circuit. Also, note that batteries give off hydrogen, so don’t allow for any sparks, cigarettes or naked flames around you when working on your battery.

Final Thoughts

If your dirt bike battery is dying very quickly, it’s probably because of one of the 10 reasons above. In order to avoid these, you should perform regular maintenance on your battery to get the most out of it. However, it’s also worth checking if you have the right battery for your dirt bike in the first place!