Modern Vespa

2007 Gts 250ie…..i hook it up to tender every winter, including this winter. I took it off tender and rode it twice in the last 2 weeks. Today, gauges and lights all blank, will not even try to turn over…i replaced battery with MotoBatt AGM a few years ago. Does this sound like a dead battery?

What reading do you get with a multimeter?

I dont own multimeter. Found receipt motobatt Battery is exactly 2 years old. Hooked it up to tender, reading is yellow, meaning battery not charged. Do these things have an alternator like a car?

I could buy a multimeter. What number would be good or bad? I am considering buying a new battery. Do MotoBatts go bad very often? Admittedly, Illinois winters are harsh. It sits in an attached garage all winter….

O'Reilly, Autozone, Advance, Napa all should be able to test the battery free if you don't have a multimeter. Or you could pop to any of those stores, Walmart, (or even on Amazon if you don't want to leave the house) and buy a multimeter.

Its a 12-volt battery. What is a healthy readout? After bring on the tender for 90 minutes, if i turn key, it whirrs, readout flashes, then goes blank….

Put it on the tender for 24 hours at least. Then disconnect the tender, and leave it alone for at least an hour. After that it (being a Motobatt AGM) should read round-about 12.7 to 12.8V. This doesn't mean it can supply enough current for starting though.

Expect to pay ~$7 to $10 for a cheapo multimeter, which is all you need. Harbor freight etc...

I strongly suspect the battery has died. I've had no luck with Motobatts - the two I've had died within six months, despite nearly daily use.

These days I recommend getting a LiFePO4 (LFP, lithium iron) battery instead of a lead-acid. Higher voltage (13.2V), over 5,000 charge cycles, and can deliver full current right down until it's at 10% charge, unlike lead-acid, which peg out at 50% and get damaged if discharged further. They are now equivalent in price to lead-acid.

Yes, your bike has an alternator. It also has a regulator. Testing the charging system is fairly straightforward - read the Wiki:
Diagnosing Charging System Problems

Update….it WAS a dead battery…..i pit on a new AGM Motobatt 2 years ago. Was expecting battery to last longer than 2 years…..

2 years is about average and they tend to go out suddenly with no warning and long before they're completely dead dead, all sorts of things will lead to a short battery life though

One can purchase a battery tester inexpensively, and check the battery on occasion. I have one, and it warned me that my car battery needed replacing. I didn't believe it. Not two months later, the battery died.