I’m writing this post a little bit late… as our flat battery problem happened beginning of February! We’ve been travelling quite a while since then, and very busy with our work when in Madrid, so I couldn’t write this post earlier. My apologies for that!
So, let’s go to business! The battery…. Yes, this infamous Banner standard battery equipped in our Morgan 3-Wheelers… Why “infamous”? Because we are too many complaining about this battery that our little rockets equip as a standard.
The exact model is the Banner Starting Bull 530 30. It looks nice, with a red angry bull charging out of a yellow flame-looking explosive background. But don’t get fooled by its looks… It’s famous for getting flat without any previous warning. At random. Any moment, any place. Some get flat after few months, and others last for years. In our case it lasted two years, clearly too short for an average quality battery. So, it’s not average quality, but poor. At least from our experience. Therefore, driving the car with this battery onboard is a little bit like playing the Russian Roulette. It’s clearly one of those weak points you must get rid of as soon as possible.

It’s true that the 3-Wheeler is not a car that you use daily, therefore using a battery conditioner is always a good idea if you don’t plan to start and run the little rocket at least every two or three weeks. But here in Madrid it doesn’t rain that much, and, despite it can be very cold in winter, we drive the Morgan every two weeks, or three weeks maximum, and long enough to make sure that the battery gets a good amount of “juice” from the rectifier.
We go down to the garage the 5th of February, to enjoy a short Saturday drive in Madrid. Four weeks since the last drive, longer than usual, and we find the voltmeter below 9V… The Morgan doesn’t even try to start.
For a very short time, we consider reviving this Banner battery. I look on the internet to buy a portable jump starter, but this idea doesn’t convince me much. Because the S&S engine is not precisely a quick-starting motor. And most of the portable jump starters won’t give enough seconds of full amperage. They may not have “enough juice” for the 7- or 10-seconds of the S&S V-Twin cold starting procedure. And we know the standard Banner is not the best battery… investing money trying to revive it will just extend the agony and will be more expensive at the end of the day.
I discuss the matter with Ana Maria, and we finally decide to change the battery. But which one is the best alternative to the original Banner model? I look into the fantastic “M3W Alternative Parts List” file. An amazing and incredibly useful file created by Ian Brett – AKA Planenut in our beloved Talk Morgan forum – in which you find the most interesting and reliable alternative parts to replace the standard ones that our M3W equips from factory. The list shows up to fifteen possible battery candidates!
I then chatted with my good friends of M3W Services asking for their personal advice. They totally convinced me to change the battery and forget about the portable jump starter. We’re definitely on the right path.
I’m looking for a direct replacement. Or at least a good battery that doesn’t imply big modifications underneath the bonnet. Because there is no perfect match to the Banner’s dimensions. And under the 3-Wheeler bonnet there is not much room for modifications. I read carefully the Banner Starting Bull 530 30 specifications, to make sure I buy a battery with the same, if not better characteristics.

The Starting Bull 530 30 has these dimensions: L187mm, W128mm and H165mm. None of the alternative batteries’ dimensions are exactly the same. An additional obstacle in our case is that we built a storage to keep the main tools’ bags under the bonnet, precisely very close to the battery, as you can see in the next image.

The one on the M3W Alternative Parts List that most attires my attention is the Magnetti Marelli MM-ion15. It has a very similar size than the Banner – slightly smaller – and it’s a high-performance lithium battery. On the top of that, it happens it’s the model that Chas uses in his “Black Adder” 3-Wheeler. And with excellent results! He tells me that the first one he put in lasted for seven years! Magnetti Marelli it will be!
I buy one on the internet. It’s not a cheap battery, been a lithium one and with very good characteristics: 264,84 € in Amazon. And we receive it a couple of days after ordering it.

I never had a car or motorcycle lithium battery before, and I’m absolutely amazed with the weight. It’s so light I even think it’s fake! It’s really astonishing. Only 1.988 grams! The original Banner weights 8 kilograms! What a huge difference!

The change of the battery is easy. The Banner is out in a few minutes, and the Magnetti Marelli is in really fast. However, I find a little problem: the metal plate that retains the battery, which is screwed via two long metal yokes, hooked at the battery base under the bonnet and with threaded upper end where the retaining plate and a couple of nuts go, don’t keep solidly enough the new battery. Because the yokes are too long, designed for the taller Banner battery, and the threads not long enough for the nuts to fix down the retaining plate.

But this little issue is easily fixed by sticking below the plate a couple of Teflon skates. The kind you stick below the feet of your furniture or the legs of your tables, to move them easy and without scratching the floor. Cheap and easy solution, for less than 5 Euros.

Now the plate makes enough downforce on the battery, so it doesn’t move at all. And another advantage is that the skates are made of Teflon, so there is not a direct touch of the metal plate over the battery, and it won’t be scratch nor damaged in any way.
Here below you have a few pictures of the final result.

After all the fixing and cabling, Im about to start the engine, still been sceptic because of the super-light new battery. Can this really give more crank amperage than the heavy Banner? The answer comes a couple of seconds just after pushing the start button! The engine fires up immediately. Wow! I’m happily surprised.
I drive to the dealer’s workshop to give them the old dead Banner battery for them to recycle it, and chat with them about the new Magnetti Marelli I just installed. Those guys are always interested and pay a lot of attention to all the modifications I make in my 3-Wheeler. It wouldn’t be the first time they ask me for advice! Now they know about a much better battery!
Since the change, we notice a real improvement, as our M3W starts faster. This new lithium battery is really an excellent choice. We hope it will last many years from now!