There’s nothing quite like the feeling of gearing up for a ride, hopping on your 2021 Polaris Sportsman 570, turning the key, and hearing… nothing. A dead battery can kill a perfect trail day before it even begins. We’ve all been there, and it’s a frustration every rider wants to avoid.
You know you need a new battery, but searching online brings up a confusing mess of codes, types, and sizes. Choosing the wrong one means it won’t fit, won’t have enough power, or worse, could leave you stranded miles from anywhere.
In this guide, we promise to cut through the noise. We’ll give you the exact 2021 polaris sportsman 570 battery size you need, break down the pros and cons of different battery types, and walk you step-by-step through the replacement process. You’ll learn how to choose the perfect battery for your riding style, install it safely, and keep it running strong for years to come.
What is the Correct 2021 Polaris Sportsman 570 Battery Size?
Let’s get straight to the point. The factory-specified, or OEM (Original Equipment Manufacturer), battery size for a 2021 Polaris Sportsman 570 is a YTX20L-BS.
This isn’t just a random string of letters and numbers. Each part of that code tells you something critical about the battery’s design and fitment. Understanding this code is the first step in our comprehensive 2021 polaris sportsman 570 battery size guide.
Decoding the Battery Code: YTX20L-BS
- YTX: This is a manufacturer designation for a high-performance, sealed AGM battery. It’s a common prefix for powersports batteries.
- 20: This number indicates the battery’s power rating. A higher number generally means more power capacity and a physically larger battery.
- L: This is one of the most important letters! It stands for “Left” and tells you that the negative terminal is on the left side when you are looking at the front of the battery. Getting this wrong means your cables won’t reach.
- BS: This indicates that the battery is a “Bottle Supplied” sealed battery. It’s factory-sealed and maintenance-free.
Key Battery Specifications to Always Verify
While YTX20L-BS is the standard size, it’s always smart to double-check these three specs before you buy. Think of it as the “measure twice, cut once” rule for your ATV.
- Physical Dimensions (L x W x H): The standard YTX20L-BS size is approximately 6.875 inches (L) x 3.4375 inches (W) x 6.125 inches (H). Your battery tray is built for these exact dimensions. A battery that’s too big won’t fit, and one that’s too small will vibrate excessively, leading to a shorter lifespan.
- Cold Cranking Amps (CCA): This is the muscle. CCA measures the battery’s ability to start your engine in cold weather. Your Sportsman 570 needs a battery with at least 270-310 CCA to reliably turn over the engine, especially if you ride in cooler climates or have accessories like a winch.
- Terminal Polarity: As mentioned, the “L” means the negative post is on the left. Always visually confirm this on the new battery. Hold it with the terminals closest to you and ensure the negative (-) is on the left and the positive (+) is on the right.
Choosing Your Upgrade: AGM vs. Lithium Batteries
The OEM battery is a reliable AGM (Absorbent Glass Mat) unit. But you have options! The choice between AGM and a Lithium upgrade depends on your budget, riding style, and power needs. Understanding the benefits of 2021 polaris sportsman 570 battery size and type is crucial.
The Reliable Workhorse: AGM (Absorbent Glass Mat)
AGM batteries are the go-to for most riders. They contain a special fiberglass mat that absorbs the electrolyte, making them spill-proof and highly resistant to the heavy vibration that comes with off-roading.
- Pros: Proven technology, very durable, maintenance-free, excellent vibration resistance, and more affordable upfront.
- Cons: Significantly heavier than lithium, has a shorter overall lifespan (typically 3-5 years), and can lose charge faster in storage.
The High-Performance Option: Lithium (LiFePO4)
Lithium Iron Phosphate (LiFePO4) batteries are the new-school upgrade. They offer incredible performance benefits, but at a higher price point. If you run a winch, extra LED light bars, or other high-draw accessories, a lithium battery is a serious contender.
- Pros: Extremely lightweight (often saving 5-10 pounds), much longer lifespan (can last up to 10 years), holds a charge for months in storage, and provides stronger, more consistent cranking power.
- Cons: Higher initial cost, and you must use a lithium-compatible battery charger or tender to avoid damaging it.
Which One is Right for Your Rig?
For the average trail rider who uses their Sportsman for recreation and light work, a quality AGM battery is a fantastic choice. It’s reliable, tough, and cost-effective.
If you’re a serious mudder, a performance enthusiast, or someone who relies on power-hungry accessories like a big winch or stereo system, the weight savings and superior power of a lithium battery are well worth the investment.
How to Replace Your 2021 Polaris Sportsman 570 Battery: A Step-by-Step Guide
Alright, you’ve picked your new battery. Now it’s time to get your hands dirty. This is a simple job you can easily do in under 30 minutes. Following this guide on how to 2021 polaris sportsman 570 battery size replacement will ensure a safe and successful install.
Tools & Safety First
Gather your gear before you start. You don’t need much:
- Socket wrench with a 10mm socket (most common size for terminals and hold-downs)
- Safety glasses
- Mechanic’s gloves
- A small wire brush
- Dielectric grease (highly recommended)
Safety is non-negotiable. Always work in a well-ventilated area. The golden rule of battery replacement is: Negative Off First, Negative On Last. This prevents accidental short-circuiting if your wrench touches the frame.
Step 1: Locate and Access the Battery
On the 2021 Sportsman 570, the battery is typically located under the front storage rack. You’ll need to remove the plastic cover to gain access to the battery compartment.
Step 2: Disconnect the Old Battery
Remember the rule! Use your 10mm socket to first loosen and remove the bolt on the negative (black, “-“) terminal. Tuck the cable aside so it can’t accidentally touch the post again.
Now, repeat the process for the positive (red, “+”) terminal.
Step 3: Remove the Old Battery and Clean the Tray
Undo the battery hold-down bracket. This is usually a rubber strap or a metal bar held in place with one or two bolts. Once it’s free, carefully lift the old, heavy battery out of the tray.
This is a perfect time for a little preventative maintenance. Inspect the battery tray and cable ends for any white or greenish corrosion. If you see any, clean it off with your wire brush and a paste of baking soda and water. Rinse with a little clean water and dry thoroughly.
Step 4: Install the New Battery
Carefully place your new battery into the clean tray. Ensure it sits flat and doesn’t rock. Re-install the hold-down bracket and make sure it’s snug. A loose battery will vibrate, which is a leading cause of premature failure.
Step 5: Connect the New Battery
Now, you do the reverse of the removal process. Connect the positive (red, “+”) terminal first. Apply a small dab of dielectric grease to the terminal and post to prevent future corrosion, then tighten the bolt securely.
Finally, connect the negative (black, “-“) terminal. Apply grease and tighten the bolt. Give both cables a gentle wiggle to ensure they are tight and won’t come loose on the trail.
Replace the plastic cover, and you’re done! Turn the key and enjoy that crisp, powerful start.
Common Problems with 2021 Polaris Sportsman 570 Battery Size and Fitment
Even with the right info, you can run into hiccups. Here are some of the most common problems with 2021 polaris sportsman 570 battery size and how to solve them.
Problem: The New Battery is Too Tall or Wide
This usually happens when you buy a battery with a similar power rating but a different group size. Always stick to the YTX20L-BS size designation. If you’re buying in person, bring your old battery with you to compare side-by-side.
Problem: The Terminals are on the Wrong Side
You accidentally bought a YTX20-BS (positive on the left) instead of a YTX20L-BS (positive on the right). Your cables won’t reach. Unfortunately, the only fix is to return it for the correct model. Always double-check that “L”!
Problem: The ATV Won’t Start After Installation
Don’t panic. Check the simple things first. Are the terminal connections clean and tight? A loose connection is a common culprit. Did you accidentally leave a light on or the key in the “on” position? Also, check the main fuse near the battery to ensure it didn’t blow.
The Ultimate 2021 Polaris Sportsman 570 Battery Size Care Guide
Your new battery is an investment. Following these 2021 polaris sportsman 570 battery size best practices will maximize its life and performance.
Regular Charging and Tending
The single best thing you can do for your battery, especially during long periods of storage, is to use a smart battery tender or maintainer. These devices monitor the battery’s voltage and deliver a slow, steady charge only when needed, preventing both overcharging and sulfation.
Keep Terminals Clean
Every few months, take a quick look at your battery terminals. If you see any corrosion starting to form, clean it off immediately. Dielectric grease applied during installation is your best defense.
Check for a Secure Fit
Vibration is a battery’s worst enemy. Whenever you’re doing other maintenance, give the battery a quick push to make sure the hold-down bracket is still tight and the battery isn’t rattling around in its tray.
Sustainable and Eco-Friendly Battery Choices
Being a responsible rider extends to how we handle our parts. Thinking about a sustainable 2021 polaris sportsman 570 battery size solution is easier than you think.
Choosing Longevity
The most eco-friendly 2021 polaris sportsman 570 battery size choice is the one you replace least often. While a lithium battery has a higher upfront cost, its 8-10 year lifespan means you’ll be buying (and disposing of) far fewer batteries over the life of your ATV compared to replacing an AGM every 3-4 years.
Proper Battery Recycling
Lead-acid batteries are highly toxic and must never be thrown in the regular trash. The good news is they are also highly recyclable. When you buy a new battery, the auto parts store will take your old one. They’ll often give you a “core charge” refund for bringing it back, ensuring it gets disposed of properly.
Frequently Asked Questions About the 2021 Polaris Sportsman 570 Battery
What is the factory battery size for a 2021 Polaris Sportsman 570?
The standard OEM battery size is a YTX20L-BS. This size provides the correct physical dimensions, terminal location, and power capacity for your machine.
Can I use a different size battery in my Sportsman 570?
It is strongly discouraged. Using a battery that is too small will not provide enough cranking power and will vibrate in the tray, leading to a very short life. A battery that is too large simply will not fit in the designated compartment.
How long should a Sportsman 570 battery last?
With proper care and use of a battery tender, a quality AGM battery should last between 3 to 5 years. A lithium battery, while more expensive, can last much longer, often 8 to 10 years.
Do I need a special charger for a lithium ATV battery?
Yes, absolutely. You must use a charger specifically designed for LiFePO4 (lithium) batteries. Using a standard lead-acid charger can permanently damage a lithium battery and even create a safety hazard.
Choosing and installing the right battery for your 2021 Polaris Sportsman 570 is a straightforward job that pays huge dividends in reliability and peace of mind. By understanding the YTX20L-BS size, weighing the benefits of AGM versus Lithium, and following a proper maintenance routine, you’re ensuring your quad is ready to fire up whenever adventure calls.
Now you’re armed with the expert knowledge to get the job done right. Get that new battery in, fire up your rig, and we’ll see you on the trails!
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