Modern Vespa

I was in a hurry and had a careless moment, leaving the ignition knob turned to the right on my 2023 Vespa GTS, went to ride this morning and it was dead.
I have had it on a charger for 2 hours and the immobilization light and seat lock have enough power to work.

Two questions:
1) How long should I leave it on the charger?

2) We have bad thunderstorms and may not be able to ride after I take it off the charger, will that be an issue?

You can see the volts in the dashboard when the ignition is on. It should be 12.8 or more... It doesn't hurt to leave the charger plugged in for a day.

As long as the charger is plugged in/switched on, all consumers (seat bench opening, etc.) should work and the volt display should also be higher, but this says nothing about the state of charge of the battery (i.e. unplug/switch off to measure).

Bear in mind that even a single deep discharge could have irreparably damaged the battery, in which case the only solution is to replace it.

that charger does not look like a smart charger and I would not recommend more than 5 hrs on it. looks like an automotive 2/10 amp straight charger.

Without knowing the device pictured: I can't imagine that anyone would still use a charger without a protective circuit, but if that is the case, you are of course right.

It's currently reading at 10.9 after charging for four hours.

Once it's been on the charger long enough to get a full charge (and without knowing what charger or what sort and size of battery there's no way to advise that properly) then measure the volts a good hour after it's been taken off charge. As long as it reads 12.6V (for flooded/gel lead-acid) 12.8V (AGM) or 13.2V (LFP) or more then you're OK to ride with it, but...

...whether it'll hold its charge for many days after having been discharged completely is unknown - with luck, if it was discharged for less than a day you should be OK. Don't be too disappointed if you have to buy a new one, and from now on ALWAYS turn off the scooter with the key, NOT with the kill-switch.

The charger showed green, went to start it and the dash flashed and it made an intermittent moaning noise.

My 2023 has the remote key and the turn switch.

Ah. IMHO a foolish retrograde step by Piaggio.

This is the charger I am using

not an ideal charger for small scooter batteries, great for cars though.

walmart or amazon has this great charger
https://www.amazon.com/NOCO-GENIUS2-Fully-Automatic-Temperature-Compensation/dp/B07W6B987F/ref=asc_df_B07W6B987F/?tag=hyprod-20&linkCode=df0&hvadid=693401379483&hvpos=&hvnetw=g&hvrand=15472955378603813319&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9013416&hvtargid=pla-851813447228&psc=1&mcid=30e5ca08c77730188cd52633942cfac8&gad_source=1

can do lead, gel, lith

You charging at 6v and 2 amp? On a 12v battery?

"6<>2A"

I didn't see it as that - it automatically goes between 6A and 2A, that's bulk charge and maintain, and will drop to near 0A when it determines fully charged. The voltage selection is automatic. That's OK for a 12Ah m/c battery as well as a car battery.

Not knowing anything about that particular charger, I'd interpret that as 2 to 6 amps, constant voltage rather than constant current. I agree with OAD that it's not a great charger, and Noco does indeed make some really nice ones. We use a different Nico Genius model on the airplane - it's got a roughly scooter-size 12V 18AH SLA battery.

When you tried start it and it "moaned" did it ever start? If not, you probably need a new battery. I had this happen to one of my scooters this year. 2.5 year old battery... Always showed green but was actually bad. Interesting that none of my smart chargers never turned red. Here's a weird addition to the story- bought new battery from a local motorcycle shop and when I installed it the headlight came on then NOTHING. I started tracing wires, checking fuses etc. I then checked the new battery - bad. Took it back and they load tested it and sure enough - bad. Got a new one ready for me the next day and its been working great ever since.

Bob

In my experience if a battery doesn't show serious signs of life after a few hours on a charger, it probably never will.