Introduction

I am not a lawyer. I don't even play one on TV. I researched the California Vehicle Code through the official web site. I looked for every law I could find that mentions the words lamp, light, flashing, and motorcycle. This is what I found.

Auxiliary Driving Lamps (high-beam)

24402. (a) Any motor vehicle may be equipped with not to exceed two auxiliary driving lamps mounted on the front at a height of not less than 16 inches nor more than 42 inches. Driving lamps are lamps designed for supplementing the upper beam from headlamps and may not be lighted with the lower beam.

Passing Lamps (low beam)

24402. (b) Any motor vehicle may be equipped with not to exceed two auxiliary passing lamps mounted on the front at a height of not less than 24 inches nor more than 42 inches. Passing lamps are lamps designed for supplementing the lower beam from headlamps and may also be lighted with the upper beam.

Fog Lamps (low beam)

24403. Any motor vehicle may be equipped with not to exceed two foglamps which may be used with, but shall not be used in substitution of, headlamps. Foglamps shall be mounted on the front at a height of not less than 12 inches nor more than 30 inches and so aimed that when the vehicle is not loaded none of the high-intensity portion of the light to the left of the center of the vehicle shall at a distance of 25 feet ahead project higher than a level of four inches below the level of the center of the lamp from which it comes.

Spot Lamps

24404. (a) A motor vehicle may be equipped with not to exceed two white spotlamps, which shall not be used in substitution of headlamps.

(b) No spotlamp shall be equipped with any lamp source exceeding 32 standard candlepower or 30 watts nor project any glaring light into the eyes of an approaching driver.

(c) Every spotlamp shall be so directed when in use: That no portion of the main substantially parallel beam of light will strike the roadway to the left of the prolongation of the left side line of the vehicle. That the top of the beam will not strike the roadway at a distance in excess of 300 feet from the vehicle.

(d) This section does not apply to spotlamps on authorized emergency vehicles. (e) No spotlamp when in use shall be directed so as to illuminate any other moving vehicle.

Four lamps maximum

24405. (a) Not more than four lamps of the following types showing to the front of a vehicle may be lighted at any one time: (1) Headlamps. (2) Auxiliary driving or passing lamps. (3) Fog lamps. (4) Warning lamps. (5) Spot lamps. (6) Gaseous discharge lamps specified in Section 25258.

(b) For the purpose of this section each pair of a dual headlamp system shall be considered as one lamp.

(c) Subdivision (a) does not apply to any authorized emergency vehicle.

Lamp switches

24406. Except as otherwise provided, the headlamps, or other auxiliary driving lamps, or a combination thereof, on a motor vehicle during darkness shall be so arranged that the driver may select at will between distributions of light projected to different elevations, and the lamps may, in addition, be so arranged that the selection can be made automatically.

Lamp pattern distribution

24407. Multiple-beam road lighting equipment shall be designed and aimed as follows: (a) There shall be an uppermost distribution of light, or composite beam, so aimed and of such intensity as to reveal persons and vehicles at a distance of at least 350 feet ahead for all conditions of loading.

(b) There shall be a lowermost distribution of light, or composite beam so aimed and of sufficient intensity to reveal a person or vehicle at a distance of at least 100 feet ahead. On a straight level road under any condition of loading none of the high intensity portion of the beam shall be directed to strike the eyes of an approaching driver.

Lamp indicators

24408. (a) Every new motor vehicle registered in this state after January 1, 1940, which has multiple-beam road lighting equipment shall be equipped with a beam indicator, which shall be lighted whenever the uppermost distribution of light from the headlamps is in use, and shall not otherwise be lighted.

(b) The indicator shall be so designed and located that when lighted it will be readily visible without glare to the driver of the vehicle so equipped. Any such lamp on the exterior of the vehicle shall have a light source not exceeding two candlepower, and the light shall not show to the front or sides of the vehicle.

High/Low beams

24409. Whenever a motor vehicle is being operated during darkness, the driver shall use a distribution of light, or composite beam, directed high enough and of sufficient intensity to reveal persons and vehicles at a safe distance in advance of the vehicle, subject to the following requirements and limitations:

(a) Whenever the driver of a vehicle approaches an oncoming vehicle within 500 feet, he shall use a distribution of light or composite beam so aimed that the glaring rays are not projected into the eyes of the oncoming driver. The lowermost distribution of light specified in this article shall be deemed to avoid glare at all times regardless of road contour.

(b) Whenever the driver of a vehicle follows another vehicle within 300 feet to the rear, he shall use the lowermost distribution of light specified in this article.

Old vehicles.

24410. Headlamps arranged to provide a single distribution of light not supplemented by auxiliary driving lamps are permitted on motor vehicles manufactured and sold prior to September 19, 1940, in lieu of multiple-beam road lighting equipment if the single distribution of light complies with the following requirements and limitations:

(a) The headlamps shall be so aimed that when the vehicle is not loaded none of the high-intensity portion of the light shall at a distance of 25 feet ahead project higher than a level of five inches below the level of the center of the lamp from which it comes, and in no case higher than 42 inches above the level on which the vehicle stands at a distance of 75 feet ahead.

(b) The intensity shall be sufficient to reveal persons and vehicles at a distance of at least 200 feet.

Eight lamps maximum for off-road use.

24411. Notwithstanding any other provision of law, a vehicle may be equipped with not more than eight lamps for use as headlamps while the vehicle is operated or driven off the highway. The lamps shall be mounted at a height of not less than 16 inches from the ground, or more than 12 inches above the top of the passenger compartment, at any place between the front of the vehicle and a line lying on a point 40 inches to the rear of the seat occupied by the driver, shall be wired independently of all other lighting circuits, and, whenever the vehicle is operated or driven upon a highway, shall be covered or hooded with an opaque hood or cover, and turned off.

Other flashing lights prohibited

25250. Flashing lights are prohibited on vehicles except as otherwise permitted.

Turn signals, hazard warning lights

25251. (a) Flashing lights are permitted on vehicles as follows:
(1) To indicate an intention to turn or move to the right or left upon a roadway, turn signal lamps and turn signal exterior pilot indicator lamps and side lamps permitted under Section 25106 may be flashed on the side of a vehicle toward which the turn or movement is to be made.
(2) When disabled or parked off the roadway but within 10 feet of the roadway, or when approaching, stopped at, or departing from, a railroad grade crossing, turn signal lamps may be flashed as warning lights if the front turn signal lamps at each side are being flashed simultaneously and the rear turn signal lamps at each side are being flashed simultaneously.
(3) To warn other motorists of accidents or hazards on a roadway, turn signal lamps may be flashed as warning lights while the vehicle is approaching, overtaking, or passing the accident or hazard on the roadway if the front turn signal lamps at each side are being flashed simultaneously and the rear turn signal lamps at each side are being flashed simultaneously.
(4) For use on authorized emergency vehicles.
(5) To warn other motorists of a funeral procession, turn signal lamps may be flashed as warning lights on all vehicles actually engaged in a funeral procession, if the front turn signal lamps at each side are being flashed simultaneously and the rear turn signal lamps at each side are being flashed simultaneously.

(b) Turn signal lamps shall be flashed as warning lights whenever a vehicle is disabled upon the roadway and the vehicle is equipped with a device to automatically activate the front turn signal lamps at each side to flash simultaneously and the rear turn signal lamps at each side to flash simultaneously, if the device and the turn signal lamps were not rendered inoperative by the event which caused the vehicle to be disabled.

(c) Side lamps permitted under Section 25106 and used in conjunction with turn signal lamps may be flashed with the turn signal lamps as part of the warning light system, as provided in paragraphs (2) and (3) of subdivision (a).

(d) Required or permitted lamps on a trailer or semitrailer may flash when the trailer or semitrailer has broken away from the towing vehicle and the connection between the vehicles is broken.

(e) Hazard warning lights, as permitted by paragraphs (2) and (3) of subdivision (a) may be flashed in a repeating series of short and long flashes when the driver is in need of help.

Headlight modulators

25251.2. Any motorcycle may be equipped with a means of modulating the upper beam of the headlamp between a high and a lower brightness at a rate of 200 to 280 flashes per minute. Such headlamps shall not be so modulated during darkness.

Liability for non-use of turn signals

25251.3. No civil liability shall attach to any person for the use or nonuse of turn signal lamps in the manner permitted by paragraph (3) or (5) of subdivision (a) of Section 25251, except for such civil liability as would attach for the use or nonuse of any other device required by this article or Article 8 (commencing with Section 25300).

Theft alarm flasher

25251.4. Any motor vehicle may also be equipped with a theft alarm system which flashes any of the lights required or permitted on the motor vehicle and which operates as specified in Article 13 (commencing with Section 28085) of Chapter 5 of this division.

Deceleration flasher, amber flashing brake lights, red flashing brake light

25251.5. (a) Any motor vehicle may also be equipped with a system in which an amber light is center mounted on the rear of a vehicle to communicate a component of deceleration of the vehicle, and which light pulses in a controlled fashion at a rate which varies exponentially with a component of deceleration.

(b) Any motor vehicle may be equipped with two amber lamps on the rear of the vehicle which operate simultaneously with not more than four flashes within four seconds after the accelerator pedal is in the deceleration position and which are not lighted at any other time. The lamps shall be mounted at the same height, with one lamp located on each side of the vertical centerline of the vehicle, not higher than the bottom of the rear window, or if the vehicle has no rear window, not higher than 60 inches. The light output from each of the lamps shall not exceed 200 candlepower at any angle horizontal or above. The amber lamps may be used either separately or in combination with another lamp.

(c) Any stoplamp or supplemental stoplamp required or permitted by Section 24603 may be equipped so as to flash not more than four times within the first four seconds after actuation by application of the brakes.

Motorcycle headlights on at night.

25650. Every motorcycle during darkness shall be equipped with at least one and not more than two lighted headlamps which shall conform to the requirements and limitations of this division.

Motorcycle headights on while riding.

25650.5. Every motorcycle manufactured and first registered on and after January 1, 1978, shall be equipped with at least one and not more than two headlamps which automatically turn on when the engine of the motorcycle is started and which remain lighted as long as the engine is running. This section does not preclude equipping motorcycles used as authorized emergency vehicles with a switch to be used to turn off the headlamp during emergency situations or when the light would interfere with law enforcement, if the switch is removed prior to resale of the motorcycle.

Motorcycle headlight illumination requirements

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.

Colors of Lamps and Reflectors

25950. This section applies to the color of lamps and to any reflector exhibiting or reflecting perceptible light of 0.05 candela or more per foot-candle of incident illumination. Unless provided otherwise, the color of lamps and reflectors upon a vehicle shall be as follows:

(a) The emitted light from all lamps and the reflected light from all reflectors, visible from in front of a vehicle, shall be white or yellow, except as follows:
(1) Rear side marker lamps required by Section 25100 may show red to the front.
(2) The color of foglamps described in Section 24403 may be in the color spectrum from white to yellow.

(b) The emitted light from all lamps and the reflected light from all reflectors, visible from the rear of a vehicle, shall be red except as follows:
(1) Stoplamps on vehicles manufactured before January 1, 1979, may show yellow to the rear.
(2) Turn signal lamps may show yellow to the rear.
(3) Front side marker lamps required by Section 25100 may show yellow to the rear.
(4) Backup lamps shall show white to the rear.
(5) The rearward facing portion of any front-mounted double-faced turn signal lamp may show amber to the rear while the headlamps or parking lamps are lighted, if the intensity of the light emitted is not greater than the parking lamps and the turn signal function is not impaired.
(6) Reflectors meeting the requirements of and installed in accordance with Section 24611 shall be red or white, or both.

(c) All lamps and reflectors visible from the front, sides, or rear of a vehicle, except headlamps, may have any unlighted color, provided the emitted light from all lamps or reflected light from all reflectors complies with the required color. Except for backup lamps, the entire effective projected luminous area of lamps visible from the rear or mounted on the sides near the rear of a vehicle shall be covered by an inner lens of the required color when the unlighted color differs from the required emitted light color. Taillamps, stoplamps, and turn signal lamps that are visible to the rear may be white when unlighted on vehicles manufactured before January 1, 1974.

Timberwoof’s Motorcycle FAQ Appendix