According to Texas state law a motorized bicycle is not clearly defined. It could be considered a motor-assisted scooter. A motor-assisted scooter is defined as a self propelled device with:
- At least two wheels in contact with the ground.
- A braking system capable of stopping the device under typical operation.
- A gas or electric motor not exceeding 40ccs.
- A deck for a person to stand or sit while operating.
- The ability to be propelled by human power alone.
As long as your motorized bicycle fits the definition of a motor-assisted scooter, you do not need a license to ride one in Texas.
To ride a motorized bicycle on the public roads in Texas you do not need registration as long as it falls into the category of a motor-assisted scooter.
SUBCHAPTER E - Motor-assisted scooters