If it starts when you connect the charger, then you need to check to make sure you don't have a dead cell(shorted). If it was a fuse, it would not crank when you connect the charger...try a direct jump from your car (remove the cables from the bike battery and jump straight from your car/truck), if it starts it's time for a new battery. Also if you have the wires crossed it won't start but you will fry some components and smell a funny odor
........Angelis
