How To Test A Motorcycle Battery? Volt Load Testing

One of the biggest challenges motorcycle owners face is determining when their battery needs to be replaced. This is a crucial decision because a dead battery can lead to a severe problem, especially when you’re out on a long ride, and there’s nobody anywhere.

If you’re not sure when it’s time to replace your battery, you’ll need to test it regularly to know when it’s time to replace it. In this post, we’ll walk you through the steps to test a motorcycle battery so that you can determine when it’s time to replace it.

Load testing your battery can help you avoid surprises

Batteries are the true heroes of the motorcycle world, supplying us with all the power we need to hit the road. The final thing we do before embarking on any lengthy journey is to place a key into the ignition and press the start button.

Our trusty batteries deliver the rumble of life to our motors. No battery power means no ride. For a modern motorcycle, it’s just that simple.

Routinely load test your battery as part of your preventive maintenance schedule. If you are not testing your battery, you can bet that it’s not functioning correctly and could put you at risk when you least expet it to.

Why do batteries die?

Leaving the lights on or forgetting to switch off the motorbike are just a few reasons why a motorcycle’s battery might die. Another potential issue is poor wiring or a defective charging system. In this case, replacing the battery will not solve anything.  

Battery testing safety and basics

You need to be careful when working with batteries. They contain acid that can result in highly flammable hydrogen gas. For your safety, follow these precautions:

  • Review your motorcycle manual and make sure you are familiar with your motorcycle. 
  • Stay away from open flames while working with a battery. Do not smoke. 
  • Keep your working area ventilated. 
  • Wear latex or rubber gloves for your protection 
  • Check the battery for corrosion, leaks, or cracks. 
  • Tools you will need when testing the battery

Testing a battery doesn’t take a lot of tools. You will only need the following:

  • Tools to remove the saddle or side covers so you can access the battery. 
  • Safety glasses
  • Gloves
  • Digital Voltmeter (with DC scale to show tenths of a volt)

The static test

Battery testing begins with this phase. A static test confirms if a battery has fully charged. It’s simple to do as well – just use a charger, or you can take a short ride, letting the charging system do its job. Allow the battery to rest for an hour before the test. Then, perform the test while the bike is turned off. 

These steps will tell you how well your battery is performing:

  • Set the voltmeter to DC scale (range 0-24, or similar)
  • Connect the positive cable to the positive battery terminal.
  • Connect negative cable to the negative battery terminal. 
  • Check and record the voltage reading. 

A fully charged working battery should read 12.6 VDC. If it’s lower than 12 VDC, recharge the battery. Then, allow it to rest for a while, and test it again. A fully charged battery that’s rested and gives an output of between 12 and 12.6 VDC has the potential to start a motorcycle, but it may not hold a full charge. 

The Process of Load Testing

Load testing involves monitoring the voltage at the battery terminal. At the same time, the motorcycle is powered on and draws power from the battery. The biggest demand for a battery occurs during the start-up.

Here are the steps to follow:

  • Work in a well-lit and well-ventilated area.
  • Make sure the motorbike is steady, and the transmission is neutral before proceeding.
  • Place the voltmeter in a position where you can see it clearly when you turn the ignition on your motorcycle.
  • Turn the voltmeter to the DC scale (range from 0 to 24 or equivalent).
  • Ensure that the positive meter lead is connected to the positive battery terminal.
  • Connect the meter’s negative lead to the battery’s negative post. 
  • Read the voltage while starting the motorcycle, then record the result. 

You will note that before the charging system kicks in, the voltage will drop as you start the motorcycle. At 9.5 VDC, your battery’s charge capacity is severely diminished. In this case, you are bound to get stranded if you don’t replace it ASAP. 

Can you rescue and charge a dead battery?

If you have a high-quality motorcycle battery, you can recharge it repeatedly. However, if you let it drain too much, it will result in a low service lifespan and damage. 

Charging a motorcycle battery isn’t that hard. All you have to do is invest in an affordable motorcycle-specific trickle charger. Connect one end to the wall, then clamp the other end to the right terminal – the black clamp is negative, the red clamp is the battery’s positive terminal.  Fully charge the battery before you test it 

How long does it take to charge a dead battery?

Recharging a motorcycle battery might take many hours. This is determined by the amount of current demanded of the battery and the voltage available from the charger. For example, a car battery charger should never be used to charge a motorcycle battery.

Because of the difference in amperage, using a car battery charger on a motorcycle battery could fry your motorcycle’s battery. 

Conclusion

Hopefully, this article has given you some information about motorcycle batteries that you can use.

It is essential to know that a battery’s condition can be ascertained by checking the voltage and amperage at the terminals. 

A fully charged motorcycle battery should read 12.6 VDC and an amperage of 14 amps.  If the voltage is lower than 12 VDC, you will likely get stranded.

The bottom line is the best way to test a motorcycle battery is to use a voltmeter and measure the voltage at the terminals.  Do not use a car battery charger on a motorcycle battery.  

If you get stuck on the side of the road, don’t freak out. So long as you can find a friend or another rider who can give your battery a boost, you will be fine.