Your motorcycle’s battery is constantly discharging at a slow rate, even if it’s completely disconnected. This is completely normal and your motorcycle’s alternator will recharge your battery while riding.
However, if you only take your motorcycle on short trips, then the alternator won’t have enough time to charge the battery, and therefore you will have to do it yourself.
But what if your battery charger does not go lower than 2 Amps? Can you safely charge your motorcycle battery at 2 Amps or will it cause damage?
Charging a Motorcycle Battery at 2 Amps – Safe or Not?
Here’s the verdict – charging a motorcycle or an ATV battery at 2 Amps is not recommended if your battery is under 20 Ah. It will be much quicker than charging the battery at 1 Amp, but will likely cause damage to the battery.
The reason for that is motorcycle batteries are smaller and more sensitive to overcharging. Because of that, you have to be careful when charging your motorcycle battery, otherwise, you can damage it and considerably decrease its lifespan.
It’s always a good idea to use a motorcycle-specific smart battery charger as it will never go over 1 Amp while charging.
However, if you do not have a motorcycle-specific battery charger, then a good rule of thumb is to only charge your battery at 1/10th of its Amp Hour rating. For example, a 10 Ah battery should be charged at 1 Amp.
Sure, it will take longer to charge but your motorcycle’s battery will last almost 2 times longer.
How Long Should You Charge a Motorcycle Battery at 2 Amps?
Speaking of taking longer to charge, you might be wondering how long should you charge your motorcycle or ATV battery at 2 Amps?
Well, it all depends on how flat the battery is and its amp hour capacity.
When you set your battery charger at 2 Amps, the charger will supply 2 Amps per hour to the battery.
For example, a 10 Ah motorcycle battery will take around 10 hours to charge from completely flat to fully charged at 2 Amps. If the battery is at 50% charge, then it will take 5 hours and so on.
You can tell if a motorcycle battery is fully charged by measuring its voltage. A fully charged motorcycle battery should measure 12.6 V or higher.
Another good way to tell if a motorcycle battery is fully charged is by monitoring its voltage while charging. If its voltage does not increase in the span of two hours, then the battery is fully charged and is ready to be used.
Can You Charge a Motorcycle Battery While Still Connected?
Yes, charging a motorcycle battery while it’s still connected won’t cause you any trouble, as long as the battery isn’t damaged and does not go over 14.7 V while charging.
In the old days, it was always recommended to remove the battery from the motorcycle and charge it somewhere safe. Nowadays, battery chargers are pretty smart and will limit voltage and amperage depending on the battery, therefore it’s pretty safe to keep the battery connected to the motorcycle.
However, if you can, I would highly recommend you remove the battery from your motorcycle and charge it in a well-ventilated area away from any ignition sources.
It’s very rare for a battery to explode or leak while charging, but it does happen. In that case, it would be ideal for the battery to fail outside of the motorcycle, where it won’t ruin anything if it does fail spectacularly.
What Amp Should I Charge My Motorcycle Battery At?
The safest way to charge a motorcycle battery is at 1 Amp.
Although 1 Amp is painfully slow, charging your battery this way will maximize its life span, which will save you money in the long run.
However, if you’re in a hurry or don’t mind replacing batteries sooner, then you can charge your motorcycle battery at a higher amperage. Around 2-3 Amps would be the maximum that you can charge the battery at, as going over that can cause the battery to fail immediately or even explode.
Having to charge your motorcycle’s battery can be quite annoying if you don’t have a motorcycle-specific battery charger at hand.
However, it can be done as long as your charger supplies a maximum of 2-3 Amps.
Sure, it’s not ideal, but charging a motorcycle battery at 2 or 3 Amps can be done in a pinch. Charging with such high amperage might not cause damage the first time, but it surely will if done multiple times.
Ideally, you’d want to use a motorcycle-specific smart battery charger, as they will constantly adjust current and voltage depending on the condition of the battery.
Jake is the site’s primary contributor.
Motorcycles and automotive repair have been a big part of his family for generations, therefore it’s only natural that he decided to become a heavy-duty diesel tech.
Outside of work, you’ll find Jake restoring and riding rare street bikes and ATVs.