How to Test a Motorcycle Battery with a Multimeter

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Motorcycles are truly a bundle of energy, condensed tightly into the tiniest space. With all the trappings of modern man, it makes sense to make the ride as comfortable and easy as possible. The audio gizmos, indicators, blinkers, lights, and whatnots of technological advances flooding man in this age and time all want clean power to be fed constantly. 

The most dependable and popular source that has served the purposes most adequately and conveniently is the motorcycle battery. It can supply increasingly bigger and maintenance-free DC power without a lot of fuss. 

Motorcycle batteries come in different power capacities, sizes, and shapes, as the number of motorcycles donning the roads. All machine’s demands differ so much from that of the others that the motorcycle manufacturers opt to have batteries from these manufacturers. 

The charging rates of the batteries, the discharge rate, the optimum amperage, duration, and the voltage of discharge determine the electrical properties, which differentiate every battery from each other. 

What are motorcycle batteries?

Car battery charges are typical items of vehicle maintenance equipment. They are simple to use, portable, and cheap. However, when you ride a motorcycle, a battery charger is often one of the most ignored pieces of equipment in your workshop. 

A twelve-volt motorcycle battery is composed of a plastic case with six cells. Every cell consists of a set of negative and positive plates immersed in a dilute sulfuric acid solution referred to as electrolytic. Every cell has a voltage of at least 2.1 volts when fully charged. Keep in mind that it comes in different power, size, and shapes, depending on your motorcycle’s model. 

You may be aware already of the two different types of motorcycle batteries that fall into: conventional and maintenance-free. 

For the conventional type, it obliges you to continuously add water due to the normal process of water evaporating. You need to guarantee a water level between the minimum and maximum levels to prevent the battery plates from being exposed to the air.

On the other hand, the maintenance-free type sealed box, and all the acid is contained in a special plate and separator. Even with high temperatures, the maintenance-free motorcycle battery will have enough electrolytes that cover the plates.

Irrespective of whether you have a conventional or maintenance-free battery. Monthly maintenance is needed for your motorcycle batteries to perform perfectly. It will help if you keep your battery charged to full, recharging when the lights dim, the battery has not been used in over two weeks, or the starter sounds weak.

Apart from that, you must follow this basic checklist on a monthly basis. 

  • Check the inside of the motorcycle battery for mossing, sulfation, or excessive sediment
  • Charge the battery once per month.
  • Safeguard motorcycle batteries from strong shocks or impacts. Make sure you do not drop it. 
  • If you store your motorcycle for a long time, like thirty days, plug it in a good quality battery charger to keep a correct charge
  • Don’t allow the battery to stand in a discharged condition. 
  • Change the caps firmly. 
  • Ensure the exhaust tube is free of clogs and kinks. Always check the case, clamps, and cables for loose connections or obvious damage. 
  • Keep the top of your motorcycle free of dirt, dry, and clean.
  • Check the levels of electrolytes. Ensure you keep the acid level between upper and lower lines indicated on the container for conventional motorcycle batteries. 
  • Clean the terminals to prevent any corrosion. 

Understand the technical specifications of the original battery of your motorcycle

The engineers who created your motorcycle installed a battery that would allow the engine of the bike and its electrical system to perform at its fullest capacity. As a starting point, ensure the technical specs of the new battery you are considering at least match the original battery’s:

  • reserve capacity
  • voltage
  • amperage

Are you picking a battery? You would like the one that will provide you the biggest reserve capacity. Normally, reserve capacity describes how long the battery will work without being charged. Further, does the original battery have unique features? For instance, does it need other attachments such as a vent tube?

Even if you are planning a new battery that is more technically advanced than the original, you need to use the specifications of the old battery and its features to help you toward the best replacement. 

Should you test your motorcycle battery?

You will find many reasons why your motorcycle battery could die, like ignoring it for several weeks or just forgetting the ignition and leaving the lights on.

Often, you might even think that your battery is the issue. Nonetheless, you could have many other problems, such as wiring concerns or a problem with the charging system. Changing the battery is not going to fix anything, and you might only be wasting precious time and money for nothing. 

  • Find your motorcycle battery. It is typically located under or near the seat.
  • Put the multimeter on the voltage mode. Place the positive lead of the multimeter on the positive terminal of the battery and the negative lead on its negative terminal. Take note that the resting voltage must be at least 12.5 volts. 
  • Shift the motorcycle into the neutral model. 
  • Start your engine and check the voltage while doing so. The voltage will lower to at least ten to eleven volts as you start the engine on a good battery. Once the battery drops under 9.5 volts while starting the engine, it indicates that one of the battery cells is bad and should be replaced right away. 

Final Thoughts

Motorcycle batteries serve more than only motorcycles. In other instances, they can be customized and utilized in small boats or as a generator for a household. Batteries would fail without any warning. Knowing that you can take necessary precautions and be ready. 

For one, you can post a note describing when you last charged the motorcycle battery. We don’t suggest buying a cheap backup battery. Further, it will help if you don’t liken a battery to a spare tire. Batteries are more likely to lose their charge even if you do not use them.

A good thing to do is to keep the contact number of your mechanic, so you can call them in case of emergency.

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