Motorcycle lane sharing should NOT be done by either the motorcycle or the automobile driver. Automobiles and motorcycles should both be considered vehicles that need a full lane to be operated safely.
Lane sharing is prohibited in most states. Trying to ride between moving cars is simply asking for trouble. A hand out the window, a door opening, or a car suddenly changing lanes could spell disaster.
The video below shows exactly why lane sharing and splitting is a bad idea:
On the flip-side many automobile drivers will try to squeeze around motorcycles. As a motorcyclist you can discourage this by remaining in the center of the lane when being followed by another vehicle.
