The Harley Dyna motorcycle was introduced in 2006 in five different models. Dyna motorcycles have twin engines, and to make those engines come to life, you need a charged-up battery. When the battery dies and needs changing, then this is one you can change on your own without taking it to the shop. The Harley Dyna's battery hides in an enclosed battery compartment.
Remove the screw from the lower fastener of the battery cover below the seat, and put the screw in a safe place. Take off the lower fastener.
Grasp the cover, and pivot it outward. Disengage the slots on the cover from the projection on the battery tray by lifting the cover away.
Loosen the bolt of the negative ("-") battery cable with a wrench. Move the cable away from the battery.
Remove the positive ("+") cable by loosening the bolt. Remove the cable from the battery, and move the cable away from the battery.
Unclip the battery strap, and remove the battery. Now you can replace the old battery with a new one.