charging battery

Yes you can but don't go with a high amp charger I'd only do about 2amps for a car charger these Batt and car ones are both 12v so most car chargers should b fine

Ok how long should a 12v 2amp charger take to fully charge a battery just so I can keep an eye on it.

All depends on how low it is no matter what I would get a smart charger one that does not continuously charge the battery but one that floats it when it is fully charged so it does not kill it from overcharging it because it's kind of a waste spending 60+ on a battery and getting a charger that is just going to kill it charged decent one is like $60 battery tenders are good ones

Ok I'll check out the battery tenders. My bike I got doesn't have a charger and the battery is dead so I don't even know if the battery is any good. Anyone know the best way to test it?

Just have to charge it and see if the charge holds if not then at least you have a new battery charger for when you get a new battery and a new battery if kept charged right should last at least 5 years

Charge the battery to full....put it in the bike,,,take a multimeter set to DC volts and hold the probes to the battery leads,,,crank over the engine and see how low the voltage drops while introducing the starting amperage load than after see how much voltage it returns back to after inducing the load.....If the voltage drops under 10,4 volts under load and doesnt return back to almost full voltage the battery is shot and must be replaced to not damage the starter and charging system......

You can also have the battery tested at any Walmart auto center for free...Good Luck...