

⚡ Power your ride with Yuasa’s maintenance-free AGM battery — reliability you can’t afford to miss!
The Yuasa YUAM329BS YTX9-BS is a 12V, 8Ah Absorbed Glass Mat (AGM) lead-acid battery designed for ATVs and powersports vehicles. Featuring advanced lead-calcium technology, it offers 3x longer specific gravity retention than traditional batteries, a nonspillable valve-regulated design, and ships dry with an acid pack for fresh activation. Compact and lightweight, it delivers 135 cold cranking amps at -18°C, ensuring dependable starts in cold conditions without the hassle of maintenance.
| ASIN | B000N5U5VG |
| Battery Cell Composition | Lead-Acid, AGM |
| Battery Type | Lead-Acid, AGM |
| Best Sellers Rank | #54,977 in Automotive ( See Top 100 in Automotive ) #131 in Powersports Batteries |
| Brand | Yuasa |
| Brand Name | Yuasa |
| Compatible with Vehicle Type | ATV |
| Customer Reviews | 4.5 out of 5 stars 980 Reviews |
| Global Trade Identification Number | 00048493329611 |
| Included Components | Yuasa YUAM329BS |
| Item Dimensions D x W x H | 3.44"D x 6"W x 4.19"H |
| Item Height | 6 inches |
| Item Type Name | lead_acid_battery |
| Item Weight | 4 Pounds |
| Manufacturer | Yuasa |
| Manufacturer Part Number | YUAM329BS |
| Manufacturer Warranty Description | Manufacturer Warranty |
| Size | YTX9-BS |
| Terminal | F1 Terminal |
| UPC | 048493329611 |
| Unit Count | 1.0 Count |
| Vehicle Service Type | ATV |
| Voltage | 12 Volts |
C**B
Real Yuasa??
The reason I say Real Yuasa is because Ive ordered a Yuasa from another seller and what they shipped was not a Yuasa. They claim the brand they shipped is the same as Yuasa and that the companies merged which is not true according to my local Yuasa distributor rep at my local moto shop. This battery was easy to match to my bike and arrived in perfect condition. Finish, fit and operation is great. Be cautious when adding the liquid. Yes the battery comes "dry" and you have to add the battery liguid and install the cap. When installing the cap, I placed the battery on a solid surface, covered it with a rag and used a light duty hammer to gently tap the cap in place. Start tapping it in place from one end to another to insure a solid fit. The cap fits very snug so it is not possible in most cases to pop it in with your hands. Highly recommend this quality battery ***Update after 3 months*** Battery didnt last long. Wont hold a charge even when putting it on a regular or trickle charger. Questioning if its a real Yuasa now. Ive never had this problem with all of the other Yuasas Ive purchased from my local shops over the years. Waiting for a replacement battery from Powersport Superstore going on 2 weeks now. Will provide an update for the replacement battery when received. *** Update after 4 months*** I've continuously tried to work with Powersports Superstore and they are now giving me the run around. Still no replacement battery. The original battery was either just a bad apple or they're selling fakes which I've run into before. I have 3-6 year old Yuasa batteries that are still working without failure on my other bikes. My advise is to go to your local shop if possible and buy a Yuasa battery. They generally buy direct from Yuasa and that way you know you're getting the real thing. ***Update*** Im happy to report that I received a replacement battery via UPS on 12/11 from Powersports. I will install and hope that this one lasts. I previously called Yuasa on 12/11 to see if they could help and they were extremely helpful. Although they dont warranty batteries directly when sold retail, they were a big help and offered some kind of assistance after I had the battery tested by an authorized motorcycle dealer. Good company and good customer service from Yuasa. I will definitely continue to buy their products just not online. Besides, they informed me that although you can buy batteries online, you cannot return them once filled due to chemical hazard and shipping restrictions (understandable) Bottom Line: There are certain things that we should just not buy online. Support you local shops.
B**.
No need to look elsewhere for a quality AGM battery
Perfect replacement for my KTM 390 Adventure. Yuasa has been the gold standard of motorcycle batteries for decades. Ships dry, so there's no question of how "old" the battery is, no worry about how much life it has left. Adding the acid is as foolproof as it gets, anyone who finds it problematic shouldn't be maintaining and operating powersport equipment in the first place. Tap the caps into place and charge, simple as that.
G**A
Great long lasting battery
Great battery. I had this exact same model in my bike from factory for 6yrs (2019-2025). I use a battery tender to keep it charged when not in use for long periods. My gps would drain the battery otherwise.
T**E
Hard to beat Yuasa
I’ve been using Yuasa batteries in my motorcycle for decades and they seem to be the best. They last for years and provide ample warning when the are aging and require replacing. My latest Yuasa in my DR650 lasted 7 years! I knew it was time to replace it when it didn’t have the juice to start the engine for the very first time; So every start was dependable for 7 years then the first time it struggled.. replaced! That’s been my methodology over the decades with Yuasa and I’ve never been stranded. I really considered a newer Lithium Battery this go around but after reading about poor performance in cold conditions and a few stranded riders I decided to stay with Yuasa, if it ain’t broke don’t fix it..
D**E
Worth The Extra Cost
I've had my street license for 50 years, owning dozens of bikes over the 700k mi I've ridden. I tend to keep bikes for years, with 3-5 in the garage at a time. I tried the the cheaper batteries and learned my lesson. The cheapies don't last as long, and they tend to fail immediately, leaving you stranded. Yuasa's last longer, and breakdown slower, such that you notice the battery is weaker but not dead, providing the opportunity to replace at home vs on the road. The reason - virgin vs recycled lead. Yuasa only uses virgin lead, the cheap ones use recycled, causing faster breakdown, and in many cases almost instant failure - pop and you're dead on the road. Get a Yuasa, keep it on a de-sulfating cycle charger. They will last years longer and not leave you stranded.
M**A
Junk after 2 months. Not worth the risk.
My OEM Yuasa battery for my Ninja 400 lasted 5 years. I decided not to cheap out and buy another to replace it. The OEM battery was made in Thailand. The new Yuasa I received is made in Indonesia. Perhaps I'm just unlucky but my new Yuasa is only 2 months old and I noticed today that it has been leaking acid into the battery box which has been dripping onto my chain and rear shock leaving corrosive damage. The leak is coming from the bottom corner of the battery. Theres no signs of damage and the fill procedure was followed correctly. Do yourself a favor and get a Yuasa battery from a local bike shop with a warranty if possible. I cannot return this to Amazon per their policy.
T**H
Yuasa is a high-quality battery.
Appears to be a genuine high-quality Yuasa battery. Initial charge rate was 0.9 amps, hope this helps it last for a couple of years. Happy with purchase.
C**.
Great battery, but you will need to use your brain.
So this battery works the way batteries have worked for years. You get it, fill it with the acid it comes with it, seal it up, and then put it on a charger for about 4-6 hours. This is not a sign of crap - rather this is a sign of quality. If you want a battery that was fully charged at the factory and has now been sitting on a shelf for 6-12 months, go to walmart and buy that. This battery can sit on a shelf for 100 years with zero degradaion becuase the acid is not in the battery yet. Yuasa has come up with a super neat and safe/contained way to add all the acid. Then you charge it for a bit and you are good to go. If you just put the acid in and then try to ue it five minutes lated - no waiiting and no charge - you will be sad (like some of the reviews here)
Trustpilot
3 days ago
3 weeks ago