Motorcycle battery maintenance involves replacing the battery once it has been completely depleted. Even if you sometimes transport your bike on a trailer or on a dirt bike hitch carrier to reduce the time you keep your battery under load, you still have to replace it at some point.
Replacing a motorcycle battery by yourself isn’t a difficult task and does not require specialized tools that are hard to use. All you need is a proper spanner and the bike’s user manual. Here is what you need to do once you have acquired your new battery.
The service manual
Although many of us like to think that mechanical maintenance routines around our bikes are easy to perform, the truth remains that every bike is different. Therefore, what you saw in a YouTube tutorial or what you heard from a friend may not apply to the brand or the motorcycle model you own. The first thing you must do is to read the factory service manual of your bike.
It will surely help you tremendously, especially if you are doing something for the first time on your bike. Otherwise, you may spend hours trying to figure out solutions to what is, in fact, a trivial problem. The manual always provides exact information regarding your motorcycle and it’s the best source of information you have.
Access the battery
Batteries can be located in countless places on motorcycles. Depending on the model, you may find them under the seat, under the fuel tank, inside the upper right fairing, hanging to one side or the other, under the bike, etc. On custom motorcycles, builders get even more creative, placing the battery even more discreetly.
This only strengthens the previous argument regarding the service manual. Reading it, you will find out the location on your model. However, the most common places where manufacturers place the battery is under the seat, under the fuel tank or behind the side covers. Therefore, these are the items you must disassemble most of the times and put aside in order to reach your battery.
Disconnect the cable from the negative terminal
Once you see the battery, identify its positive terminal and its negative terminal. These are marked with “+” and “-” signs accordingly. Usually, the cable connected to the positive terminal is red and the cable connected to the negative terminal is black.
If you remove the negative cable first, as recommended, you lower the risk of causing a short circuit and grounding out the battery, because if you touch this cable to other grounded components, nothing will happen. On the other hand, if you start by the disconnecting the positive terminal first, you have to be more careful.
Many bike manufacturers use the frame as the ground in their electrical system, so if you accidentally touch the positive cable to the frame while the negative cable is still attached to the battery, in the best case scenario you will blow a fuse and burn yourself. If the fuses are not installed properly you may even start a fire.
After removing the negative cable from the battery, place it away from the terminal to prevent the circuit from being completed again. Also, you have to be careful not to touch it to the positive terminal, as this, too, causes a short circuit. Keep in mind that metal tools, such as spanners, may bridge the gap between terminals as well, thus grounding out the battery. As you move on to work on other tasks, you can use duct tape to temporarily keep the disconnected cable in one place.
Disconnect the cable from the positive terminal
Now that the circuit has been interrupted, you may proceed in removing the positive cable. This is often red and leads to the positive battery terminal, always marked with a “+” sign. It is now safe if you touch it to the frame or other components, as you have previously removed the negative cable and the circuit is not closed anymore.
Remove the old battery
The battery can be attached to the bike using a metal piece, a rubber strap or some foam padding that keeps it snugly placed inside a plastic housing. Depending on the motorcycle’s model, disassemble or remove the above-mentioned parts and gently pull out the battery.
Take care when removing the battery as some models feature hollow terminals. This means that there is a space which houses the nuts that hold the cables tight together with bolts that thread through. If you tilt the battery the wrong way you risk dropping those nuts into hard to reach places and it may take you hours to retrieve them.
Install the charged battery
Make sure your new battery is the same size and has enough power for your bike. Inspect the terminals and make sure they are not reversed. If you have to refill it with acid, do so before mounting it, to prevent acid spills on the bike. Be prepared to treat chemical injuries. Acid burns can be treated with bases such as baking soda or soapy water, which neutralize the burn.
If your new battery has a different footprint than the old one, you have to improvise an additional casing made out of foam or rubber. This will prevent the battery from moving or vibrating. After placing the new battery in its place, attach the cables to the corresponding terminals. If you see white or blue powder on the terminals brush it off with a wire brush.
Test the battery
Before reassembling the motorcycle’s components back together, you should test the battery. Flip the key and see if your dash lights up. If it does, then you have successfully reinstalled your battery. If it doesn’t, you still have work to do.
Check the terminal connections and make sure they are tight. Also, verify that the positive and negative cables go to the corresponding terminals and not vice versa. If they are reversed, at least a fuse will have to be replaced at best.
Finally, reassemble all the parts you took off the bike at the beginning and dispose of your old battery by recycling it.