Why Does My Motorcycle Battery Keep Dying?

A strong battery is necessary for motorcycles to start the engine, run the headlights, make sound, and fuel the electrical riding gear. But what if the new bike battery is not working and you are like, “Why does my motorcycle battery keep dying?”

Usually, a battery lasts for at least 2 years, but if it breaks down, the bike battery keeps dying for various reasons, including a weak battery, a broken stator, a malfunctioning regulator, a bad or corroded terminal, poor electrical connections and cables, and if you forget to accomplish regular maintenance. Therefore, you must fix every problem if you don’t want to risk having an accident while riding.

Don’t leave the article, as we have more battery-related issues and troubleshooting to cover. So, make sure you educate yourself more about motorcycle battery drain topics.

How long does a motorcycle battery last?

how long does motorcycle battery last

Commonly, a covered Absorbed Glass Mat, or AGM, battery lasts between 3 and 5 years, according to Motor Gear Professional. Additionally, the lifespan of acid-filled batteries is between 2 and 5 years if properly maintained.

Also Read: AGM vs Lead Acid

Why does motorcycle battery dies after a week?

motorcycle battery draining overnight

Actually, there is a possibility of your motorcycle battery dies after 3 days, noticing the motorcycle battery draining overnight, or it can stay up for 3 years properly. Even we found queries like, “I replaced the battery, regulator, and stator on my motorcycle, then why does the battery still go dead every two days?”

In case, if the motorcycle battery dies within a week, there are several possible causes, including:

  • Parasitic drain.
  • The voltage of a battery
  • Engine breakdown.
  • Rust on the battery terminals or a loose connection.
  • Defective stator.
  • Regulator or rectifier trouble.
  • Broken fuse.

Therefore, the battery will provide you with excellent performance if you maintain it properly.

See More: Motorcycle Battery Maintenance

Causes of Battery Drain While Riding

motorcycle battery keeps dying

Using an Inappropriate Battery Size

The battery will try its best to power the bike if you have a larger cc bike and are using it with a small cc battery, but it will start to fail. As a result, it’s essential to get the ideal battery for your bike.

Also Read: What Does CC Mean in Motorcycle?

Electrical System Breakdown

The first issue we’re going to highlight is a short in your bike’s electrical system, which eventually drains the battery. All of your bike’s electrical parts will stop working if the primary fuse blows or fails. A shortage in the electrical system could be caused by any cabling that doesn’t appear to be secured or has defective connections.

Charging Issue

The power needed to charge the battery by the motorcycle charging system can occasionally run out. It’s important to understand that the alternator uses alternating current to transfer mechanical energy into electrical energy in order to charge a bike battery.

Accessory Wiring Problem

Since the appropriate connection is needed, additional accessories like a radio or phone charger can cause wiring issues and require a connection. Your battery might die if you don’t check the wiring or connection.

Wiring Harness Connection Issue

A weak or missing connection is usually the result of wiring harness connectors that overheat, corrode, or become loose. Ultimately, it can harm the batteries of your motorcycle. The plastic connectors should therefore be carefully observed.

Defective Ground Connection

Your motorcycle battery is dead, right? Have you checked the ground connection yet? One of the frame’s or battery’s poor ground connections might be to blame. Additionally, you might possibly see corrosion and properly attached ground straps.

Battery Drain Caused by Parasites

Your battery may become dry as a result of the parasite draw. It can drain a small amount of current from batteries until they die.

Get a multimeter, unplug the negative cable from the battery terminal, and do a quick test. When the key is turned off, connect a lead between the terminal and the wire, switch your multimeter to the amps setting, and confirm that the reading is zero.

Related Amps: How Many Amps is a Motorcycle Battery?

A Weak Battery

When you ride your bike, a defective or weak battery might be to blame for draining it, especially if it is old. So make sure the battery is in good shape.

Overloaded Bike Battery

With all of the accessories, you must test the battery’s voltage. You might have too many gadgets if it shows less than 13.8 volts. So, never add too many accessories to the bike or battery since this will shorten the battery’s duration.

No Battery Tender Used

If you don’t ride your motorcycle at least once a week for an hour, professional bikers recommend adding a battery tender. It prevents you from having dead batteries that need to be replaced frequently.

Defective Battery Terminal Connection

A battery’s terminals are the two little metal rods that protrude from the top on either side. While it’s operating, the stator should be recharging the battery, but if there’s a poor connection, your battery won’t be receiving much of a charge.

Deteriorated Terminals

The terminals sometimes become covered with battery acid, forming a barrier between them and the cable that links to the stator. The battery will receive minimal power due to insufficient connection.

Defective Regulator or Rectifier

A motorcycle’s regulator, or rectifier, is a component of the alternator unit. The rectifier supplies the power with internal restrictions to minimize overcharging and damage to a battery.

A malfunctioning regulator or rectifier problem can develop with high mileage. As batteries can’t store AC power, the regulator, or rectifier, changes the electricity into a form that the battery can store. But if the rectifier is broken, the motorcycle battery will discharge.

Poor Stator

The stator, an alternator, helps in the battery’s recharging process. However, a faulty stator will soon drain the battery.

Heating and Vibration

The area or surroundings may be hazardous to the bike’s battery. For instance, extreme vibration or heat can be troublesome for some batteries. Usually, the interior parts of the battery are damaged by heat and vibration.

Drain of Systems

The wire assembly or any combined switch unit can generally be defective. The battery can be destroyed by a defective short circuit.

Cell Which is Dying

You can notice the battery’s capacity decreasing if you’ve reached the battery’s particular lifespan. A regular wet-cell battery may also be nearing the end of its useful life.

Upgrades or Modifications

Another significant concern is that wiring problems may be identified while making modifications like installing chargers, and LED lights. Particularly when there is poor grounding, they draw excessive voltage from the battery.

How to keep your motorcycle battery from dying: 12 Best Tips

how to keep your motorcycle battery from dying
  1. Keep in mind that the alternator, which can produce more than 70 watts of AC current, provides most of the bike’s energy requirements while the battery serves as a backup.
  2. Make sure the battery’s connections are snug.
  3. Ensure the caps on the battery compartments are tight and not leaky.
  4. Check how many extra accessories you have added to your motorcycles.
  5. If the vehicle stops running or the battery is not strong enough, you can try a jump start or push start.
  6. Maintaining its charge should be your top priority.
  7. To make sure the battery is in good shape, get a battery tender or maintainer.
  8. Clean and remove dirt from the battery’s surface.
  9. Verify your battery to make sure the liquid level is sufficient and hasn’t run out. Use pure or distilled water, put on gloves, and shield your eyes to look out for pollutants.
  10. You can set the battery on a delicate trickle charge and use the multimeter to check its health. A good, usable battery should read around 12.4 volts.
  11. If you don’t ride your motorcycle for an extended period of time, remove the battery.
  12. Make sure the battery is stored away from a concrete floor and at a temperature greater than 32 degrees.

Also Read: How to Choose a Motorcycle Battery


1. What is the problem caused in a bike due to a dead battery?

You will discover a spark plug or wire issue, bad connections, a damaged terminal, alternator or engine problems, and a lack of charge. Also, you will notice the ECU restarts and fuel pump affect the battery, and corrosion also results in poor electrical contact.

2. Why is my motorcycle battery not holding a charge?

Over time, batteries gradually lose capacity, and the most frequent reason for them to stop carrying a charge is that they have been discharged or have died.

3. Do motorcycle batteries die when not in use?

Battery life can be extended with regular maintenance. When you ride, sealed lead acid batteries can last an additional 3 years over their typical lifespan of 3 years when seated.

4. Should I charge or replace motorcycle battery?

Charge the battery first, then wait for thirty minutes. It’s okay if the multimeter displays 12.4 V. But replace the battery if the reading is less than 12.4 volts.

Final Words

We hope the article has covered every detail you need to know about the query: “Why Does My Motorcycle Battery Keep Dying?” Therefore, you need to be careful about the functionality and battery of your motorcycle to ensure it’s in good condition. Especially the main culprits are lack of charging, terminal/ground connection, loose wiring, or modifications that drain the battery so quickly. 

However, we have mentioned some helpful tips at the end, so we hope you can solve the battery dying problem. If the article helped you out, make sure you get connected to our site. We have more content regarding motorcycle difficulties.

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Hello there, My name is Lewis Elliott, and I own a service center in the United States. I currently run a four-man bike repair and restoration team. My father was a Harley Davidson mechanic, so I've spent a lot of time around bikes since I was a kid. My father taught me a lot, and with his help, I started a bike service business. I don't work alone because I own a shop. For that, I have enough free time, which I use to run this blog website. I believe that sharing knowledge is beneficial because it motivates me to learn more in order to create new blogs.

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