MMG YTZ14S Z14S Lithium Ion Sealed Battery 12V 300CCA Motorcycle Scooter ATV (MMG4)

Edited 3-30-2014 see end of review:This review will be edited/added to as needed for 5 years (from September 2013) to track how this battery progresses during our seasons.I ride whenever we do not have snow. Cold weather does not make me stop so this will be a good test of this battery.When the time came to get a new battery for my motorcycle, I tried to learn as much as I could about these new Lithium Ion (LI from now on in this review) batteries. A lot of what I've read seems contradictory, and I'm beginning to think half, if not more, is bogus published by interested parties.So, what it came down to for me was that I needed a new battery and the old school acid type never seem to last more than a few years here in Michigan. Even on a tender during the months we cannot ride often, or at all if we have snow, 3 years is all you can expect from a motorcycle battery. I wanted something else and even though I was warned about these new LI batteries by those in a forum I was asking questions in, I decided to try one out.So far, we start with 5 stars, which is kind of tough for these guys. They've nowhere to go but down. However, if this battery lives up to how it has started, it will stay at 5 stars.In the box:One batteryTwo blocksLittle baggie with new bolts to connect your wires to this batteryPamphlet telling about the batteryThis thing is light, too light seemingly for a battery. It's also small. It comes with two blocks you can snap in the bottom to help make up for the space left over from a normal sized battery. My bike needed these spacers.My bike is a 1998 Honda Aero 1100 V-Twin. Comparing this battery to my old one is night and day. Even before my old battery died, it never cranked over my V-Twin like this new LI battery does. I was truly able to hear the difference right away.It was 39°F this morning, the thing I was warned about with these LI batteries, "they do not work well in the cold". I read the pamphlet that came with the battery and did what it said, which is counter-intuitive to the old battery thinking.That is: I turned the key, and let the bike sit without trying to start it. I could see the lights start out dim, and within 5-10 seconds they came on to full brightness as the battery 'warmed up'. I hit the starter and she fired up in a second.290 "cold cranking amps" (what it says) was something to behold.If this battery lasts 5 years, I'll be happy and feel I got my money's worth. As I said in the beginning, I'll add to this review as our seasons progress.January::::End of Season.. I put my bike away. Most Winters I can ride some, this winter has been rough so I haven't touched it. I checked the battery in January and found it to be fully charged yet! Next update will be in the spring.EDIT: 3-30-2014I have not started my bike since October 2013. We've had a very harsh winter here in Michigan. I still have a foot of snow in my yard, but we had a nice rain which washed all the salt and sand off the road, and it's above freezing.. so IT'S RIDING TIME !!!With temps that dipped to -14f this winter, I was curious how this battery would handle it.I checked the battery yesterday, full charge.. and it turned my bike over right away.. However, being a largeish V-Twin, it's a cold blooded beast. I shot some ether into it (standard here in MI) for it's first start of the year,, and it started right up,, well, right up after the 5th crank. The battery had easily enough juice for a prolonged cranking session after sitting for 5 months, Impressive.I rode for a long enough ride to clear the old gas out, re-filled and parked the bike for the night. Next day, no issues what-so-ever.My review stays at 5 stars.. Next edit at the end of season or as needed..

Received the battery in good condition. My first impression, when the UPS guy handed me the box, was that this is too light to be a motorcycle battery. My CB1100 instantly lost 6 pounds when I installed it. This battery replaced the OEM AGM battery that lasted a pitiful 2 years. Batteries tend to have shorter lives here in the desert heat, but I could usually expect 3 years from a typical flooded cell battery. This is my first time using lithium technology, so we'll see how that works out. I will update this review periodically. The battery came with blocks that attach to the bottom that make it the exact size of the YTZ14S AGM battery it replaces. Fit was perfect and the lugs have spacers under them so you can install it in a well without side access (big plus on my bike). So far, I've had the battery installed for a month with no issues. I don't use a battery tender since the bike is ridden 4 - 5 days per week. Since I installed it I've checked resting and operating voltages and everything is within specs. The handy test button on top of the battery has always registered a full charge. That's about all for now. Basically, it's working just as it should.Update : After 8 months this battery is still working like new. The lithum battery's weak point is cold weather starting and I got to test it out last week. On a 34 degree morning (about as cold as it gets here) the bike cranked up on the first try. Cranking speed was just a tiny bit slower, but hardly perceptable. The following morning, at the same temp, I used the cold weather procedure of turning the ignition on and waiting 15-20 sec. before cranking (the power draw actually warms up the battery). That worked. It cranked at the same brisk speed as it does normally.Last month I accidentally left the ignition on overnight and the battery was dead by morning. The battery's internal circuitry cut it off when the voltage dropped to around 10V to prevent a deep discharge. After about 5 hrs. on a 2 amp charger it was fully charged and back to its usual good performance.So far, I've got nothing bad to say about this battery. I'll provide more updates as time goes on.Update 5/3/16 :After one year this battery is still working great. I live in Phoenix and ride year round, so it didn't sit for the winter, like many do farther north. I did notice at temps of around 30F, the cranking was a tiny bit slower, but still fine. I used the "warm up" procedure recommended for cold Lithium Ion batteries, which is to turn on the ignition (and lights) and let the battery warm itself up before cranking. At 30 degrees I turned the key, let it sit for 15 seconds and sure enough, cranking speed was back to normal. Resting voltages are still the same as they were when I bought it new, so it appears to be holding up quite well.Update : 4/21/17This battery just turned two years old in my CB1100. It has performed flawlessly that whole time and voltages are still like new. This battery has officially outlasted the stock AGM battery that came with my bike. So far, it seems to be tolerating the battery killing desert heat better than the lead/acid batteries I've used in the past. I have high hopes that this lithium battery chemistry will be the answer to the premature battery death we suffer with in hot climates (2-3 yr. life is common with a lead/acid motorcycle battery).Update :10/08/18It's been 3.5 years since I installed this battery in my CB1100. It is now the longest lasting motorcycle battery I've ever owned (38 yrs. riding in the Southwest). I remember one battery a few years ago that survived the desert heat for 3 years (2-2.5 is more typical), but this MMG battery doesn't even notice the heat. Since it turned 3 yrs. old, I've been waiting for that day when you push the starter button and nothing happens. I've been pleasantly surprised so far.I've been considering getting one of these for my old CB750 as well, but I'm thinking that the old charging system on that bike wouldn't be compatible with this new tech. The modern CB1100 provides a steady 14.1V charging voltage at idle and on up the rpm range. Older bikes like my CB750 are more variable (i.e. 13.5V at idle to 14.6V at 5K rpm). The lithium batteries like a steady charge of at least 13.9V. I think this might have something to do with issues that others are having with this battery. For now, the old bike will stay with lead/acid batteries that get replaced every few years.Edit : 04/05/19 My MMG battery turned 4 yrs old. That's twice as long as my CB1100's OEM battery lasted (AGM type). I'm convinced that this battery chemistry is the answer for us desert dwellers that suffer premature battery death due to the heat. This battery has lasted longer than any motorcycle battery I've owned in here in the desert (39 years riding). I've already got my money's worth out of it. Any more months/years of service are just gravy.

I am blown away!! I just got off the phone with Amazon Support. I purchased 3 Batteries from Powersports Depot through their Amazon Store. All Batteries were dead and useless within a few months after purchase. I located the Manufacturer Modcycles in Florida who claimed that their batteries should last at least 5 to 6 years. But at the same time, they state that they will not warranty anything as this is the dealer's (Powersport Depots) obligation. I located a phone number for Powersports Depot and called multiple times over several days, leaving messages, without any callback. Amazon states there is nothing they can do. I brought to their attention that this battery and this seller have over 11% reviews that all deal with the same issue/problem without any recourse for the customer. And of course, they are deeply sorry and really understand my frustration.....but they are not going to do anything about it....So think about that before you buy anything form these folks...