Havent started my bike in about 2months. Went to start it, it took a while. It cranked then clicked like the battery was weak from sitting. It cranked over finally and let it run for about 20 mins. After about 2 weeks i went to start it again and it wont start. U can hear it cranking for like3 secs and then it will click like the battery is weak. I checked the fluids in the battery it was low so i bought some distilled water and filled it up to the upper part of the battery. Still the same. Should i get a new battery or charge it up? Or is this the battery. BTW, i have a 2005 ninja 500r. Thanks