How much should the alternator put out at idle?

I went to start my bike today and the battery was dead. So I threw it on the quick charger and started it and put my multimeter on the leads to see how much voltage was going through it and it was at 11.56 volts about. I gave it a little throttle and it hopped up to right around 14. Is this normal?

Also, I am unexperienced with these little batteries and the guy at the store threw the acid in and said "yea just throw it in right when you get home". I have talked to a couple people and was told otherwise. So I put it on the trickle charger overnight and I guess we will see what happens. I will test for parasitic drain too. Just wondering if voltage is supposed to maintain battery at idle and charge at higher rpms because that seems to be the case. The battery is about 3 weeks old too.

 

The alternator does not charge at idle, it charges with a little bit of rpm, I think it is 2500 rpm but I dont really remember exactly. That is why your headlight is usually a bit dimmer at idle as well

 

11.56 is to low. 12.5 to 12.90 is a good batt. If 13. or
more then you're over charging.

14. is fine from the alt-usualy above 2k rpm (or there abouts)
depending on the bike.

 

It's not even worth trying to measure alternator output at idle. The regulator/rectifier doesn't let the alternator do anything until you get to around 2200rpm; below that it's all battery.

A new battery, with acid freshly added like you're describing, does need to be charged before use. Don't charge at anything higher than about 1.2A/HR or you'll cook it. A 1A charger (or even .75A) is ideal.