Cal. Vehicle Code § 25651

The headlamp upon a motor-driven cycle may be of the single-beam or multiple-beam type, but in either event, when the vehicle is operated during darkness, the headlamp shall comply with the requirements and limitations as follows: (a) The headlamp shall be of sufficient intensity to reveal a person or a vehicle at a distance of not less than 100 feet when the motor-driven cycle is operated at any speed less than 25 miles per hour and at a distance of not less than 200 feet when operated at a speed of 25 to not exceeding 35 miles per hour, and at a distance of 300 feet when operated at a speed greater than 35 miles per hour. (b) In the event the motor-driven cycle is equipped with a multiple-beam headlamp, the upper beam shall meet the minimum requirements set forth above and the lowermost beam shall meet the requirements applicable to a lowermost distribution of light as set forth in subdivision (b) of Section 24407. (c) In the event the motor-driven cycle is equipped with a single-beam lamp, it shall be so aimed that when the vehicle is loaded none of the high intensity portion of light, at a distance of 25 feet ahead, shall project higher than the level of the center of the lamp from which it comes.