Please don't go replacing things until you have the problem figured out! The first thing you need to do is either charge the battery at a low amp like was said less than 2 amps. While you are waiting fo it to charge check all of your fuses. After it is charged hook everything up. With a multi meter check your voltage at the battery. With the key turned off the voltage should be between 12-13 volts. Now start the bike and measure the voltage with a multi meter again, running it should be over 13.5 and it should actually be closer to 14 volts. You can try blurping the throttle and see if your voltage fluxuates. If this all checks out then your charging system should be ok and its time to start looking for whats drawing too much current at idle. But check all of these things before you go spending money and then let us know what you find out! These are the first things I would do and have done and seams like a logical step to me. Goodluck!