Modern Vespa

CRAP! I ordered a new Motbatt AGM battery for my LX150. I thought it had the YTX12BS in it as OEM, so I bought the MBTX12U. I didn't know until I got the old one out that it is a YB9B. I need a MB9U.

The new one barely fits, but there is no room for the wires and one end of it would sit on the shock stud. There is no room for the tray that came with the new battery.

I am bummed. I had no idea I had the little battery.

EDIT: Has anyone successfully swapped out the YTX12BS for a YB9B?

MotorSoort sells the tray that allows you to put the larger battery in. I think it's about $14. I swapped mine out. You don't realize how little the battery is until you put it near the bigger ones. The stock tray is deceiving.

Yep, you just need the right tray in the bottom of the well.

You'll be much happier with the bigger battery.

I don't know why Piaggio puts the little battery in there in the first palace.

Well, I got to looking. The new battery has its own tray and a spacer that are snapped on to the battery. I removed them and tried the battery. It sat lower, but one corner was on a screw that helps secure the fuel tank. Not good, so I installed the tray without the spacer and was able to fit it in. Tight, but in. The next problem was not enough room for the wires. I was able to move them enough to connect, but I had to trim a bit off the large cover. I had to use a terminal riser on the negative cable and the positive lug I screwed direct to the terminal. Then, I still had the Stebel Horn wire and the wires for the Battery Tender Jr. I still don't have those connected yet.

Anyway, I tried it and could not believe how quickly it fired up. It was as close to instant as you could imagine. I am pleased with this new battery.

Still, I need a tiny bit more room to be able to install the battery cover and the other 3 wires. The battery needs to be scooted over toward the kick start just a tad. The shock mount is in the way. However, it is against the new battery's tray, which is a bit thick on the end.

So, I ordered an ET4 battery tray and hope that will do it. I will report back then. I might even show a pic.

Hmm. My LX is a 2007, and it had the YTX12bs battery in it when I bought it slightly used. There is absolutely no extra room under the battery cover, but everything fits.

Well, I got the new battery tray from Scooterwest. It was a perfect fit and allowed the new battery to find a home.

The Mottobat AGM battery has four terminals and risers, if needed. It is a tight squeeze to get the stock Vespa positive wire connected because it has bulky ring connector and a couple of other wires are bundled with it and covered with a protective layer. The terminal that the wire will reach to has a relay mounted in front of it. I needed to relieve the tank cover to prevent pressure on the connector. I also had to clip off one of the mounting lugs on the battery cover because there was just no room around the wire.

The negative end was not too much of a chore. Lots more room on that end.

I was able to connect the positive lead from my Stebel horn to the other positive terminal, but had to once more notch the tank cover and the battery cover to clear the wire. I have it all connected, the cover on and it starts right up.

The last problem is the Battery Tender Jr connections. Again, no problem with the negative connector. I used the second negative terminal on the battery. The problem is, I can't connect the positive lead because its ring terminal is large and it won't fit under the battery cover anyway because of the in-line fuse. I need to re-think this.

My Battery Tender lead with its in-line fuse fits on mine only because I was able to tuck it into the recess on the top of the battery between the terminals. No extra room there...

The Motobatt doesn't have a recess. In fact, the terminals themselves are below the surface.

You bought the tray from scooterwest, what was the part number? I need one.

573128 ET4 Battery Tray (Fits LX 150 w/YTX12BS Battery) $14.95