Perhaps you should have been riding in the right slot of your lane, Japanese roads being where you drive on the left. This is referred to as lane control. Riding in the slot of your lane near the edge of the road is sometimes seen by stupid cagers as you ceding the right to your lane, as when bicycles ride along the edge of the road. You are more visible in lane when you are closer to the lane divider line.
Cagers are frequently stupid, riders need to do what they can to maximize visibility.
