Ahh, 12 hours would fun. Maybe a little less. 5 amp battery, 2.5 charger, so long as ohms law is still the same, divide the 2.5 amp charger into the 5 amp battery - sounds like 2 hours to me. Double check and DONT OVERCHARGE.
Remove the battery from the bike, choose somewhere well ventilated. Don't stand or look directly over the battery. Turn the charger off at the wall before connecting or disconnecting the leads.
The Guzzi is a big bike to crank for a little battery - you'll likely be okay unless the cells reverse charged.
It’s diametrically opposed to the sanitised existence of the Lemmings around me in the Dilbert Cartoon hell I live in; it’s life at full volume, perfect colour with high resolution and 10,000 watts of amplification.
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