Take one of your strong characters (i.e., most health, strongest weapon) but not the Ridepod, and go to a dungeon that you can get minimal damage done to you. Kill the enemy with your strong person, and immediately afterwards, press L3 to switch characters or R3 to switch to the Ridepod. This is especially useful when trying to build up the Ridepod since he loses fuel easily. This makes it so he does not move or get hurt.