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There are two scenarios where I sometimes have to charge the battery on my dirt bike: (1) during the winter to keep the battery fresh, and (2) if I accidentally leave the key in the “on” position after finishing a ride.
Charging a dirt bike battery is very simple. You’ll simply remove the side panel on the dirt bike to find the battery, and then put a smart charger on the battery terminals. It will usually take about 4 hours to fully charge the battery.
Get a Good Quality Smart Charger
A smart charger is the very first accessory I would buy after getting a dirt bike if your bike doesn’t have a kick starter. The one that I have and can highly recommend is the Ctek smart charger. Unfortunately, that one isn’t available anymore but a replacement made by NOCO Genius (see on Amazon here) is another great choice. It’s reasonably priced for a very capable charger, is easy to use, and comes with the connections you’ll need for it to work on any brand of dirt bike battery.
There are many less expensive chargers out there that are trickle chargers only, and not smart chargers. If you just get a regular charger, you have to set a timer and go out and unplug it when the battery is full or you’ll risk damaging it. With this charger, it does all that for you and will turn itself off when the battery is full.
I can confidently say that this charger will save you money in the long run. If you read the reviews of this charger, you’ll see dozens of people who tried other chargers that didn’t work to revive a battery that had been completely drained, but this one did the job. If this charger saves you even one time of reviving a dead battery, it will have paid for itself.
Seriously, get a Ctek or other good quality charger and you’ll be glad you did. I’m sure there are other good brands, such as the Battery Tender that some people like, but I’m sticking with my recommendation of getting the NOCO smart charger on Amazon.

How to Charge the Battery
Once you have a good charger, this part is easy. You’ll simply take a wrench and remove the side panel on your bike by removing the 3 or 4 bolts that hold it in place. From here, you’ll easily see where the battery is. On my son’s Honda CRF110, it’s on the left, but on the TTR50 and the TTR230, it’s on the right.
Once you’ve found the battery, you’ll simply remove it from the bike. You could actually keep it in the spot if you like, but you’ll obviously want to unplug the wires from the bike to the terminals of the battery.
The smart charger has clamp-style charging ends that you can simply clip onto the battery terminals. Then plug in the charger and it’ll do its thing.
How Do You Know If a Battery Can Be Charged, or If It Has To Be Replaced?
The easy way is to simply charge the battery and see if the battery holds a charge. If you’ve left the battery out all winter without putting it on a charger, though, there’s a good chance it’s dead. Putting it on a good charger like the Ctek MIGHT revive it, but batteries can certainly just die. In this case, you’ll need a new battery.
You can certainly go to a dirt bike products store to get a new battery, but make sure they have some other brands available. I made the mistake with my son’s bike of going into the shop and they sold me an $89 Honda battery. Later, I found out that there are lots of other brands available for close to half the price for the same thing. If you can wait two days for delivery, just get the dirt bike battery on Amazon.
If you want to make this process simpler so you don’t even have to remove the battery from the bike, you can get this extension for the NOCO charger so that there’s a convenient plug sticking out of the bike to plugin quickly. That’s what I did to my TTR230 and it makes the process much faster and easier. It also makes it so I can easily monitor the charge of the battery with just a glance.
How Fast Should You Charge the Battery?
It’s best to charge your battery slowly. The faster your battery is charged, the worse the retention rate will be, and it can also damage the battery. I charge my dirt bike batteries at .8 amps. This takes a little longer but helps the battery to last.
For me, it takes about 4-5 hours for the smart charger to say the battery is full.
How to Prevent Your Battery From Dying Over the Winter
If you simply take the battery out of your dirt bike and put it on a Ctek smart charger over the winter, your battery will be in perfect condition when you go back to ride in the spring. Otherwise, there is a very good chance you’ll be paying for a new battery every single year.