Most modern motorcycles have a very simple machine set up. It is often not difficult to identify where and what its problems are. This is the same for the Harley Davidson sportster. Harley Davidson sportsters have a very simple battery set up. It is always easy for owners of this type of motorcycle to replace and change parts, lights and batteries, all you need are simple motorbike tools and you're good to go.
Turn off your motorcycle. Put on a pair of work gloves and unscrew the seat. Remove the seat and you should be able to see the battery.
Unstrap the batteries from its holding place. Use the socket wrench to loosen the bolts and cables that hold the battery.
Lift the battery slowly out of its place. Make sure all the bolts and cables are lose before taking the battery out of its lodge. Replace all the caps that you have removed back in the motorbike.
Make sure the working area or the garages you are in are free of small debris and litter. Motorbikes have very small nuts and screws and parts that easily get mixed in and lost in a crowded environment.
Check all other cables of the bike for leaking oil or gasoline. Volatile liquid is dangerous while working near them.