Interpretation ID: 1985-01.3

TYPE: INTERPRETATION-NHTSA

DATE: 01/02/85

FROM: FRANK BERNDT -- NHTSA CHIEF COUNSEL

TO: ROGER HAGIE -- MANAGER, GOVERNMENT RELATIONS KAWASAKI MOTORS CORP., U.S.A.

TITLE: NONE

ATTACHMT: LETTER DATED 10/19/84 FROM ROGER HAGIE TO NHTSA, REQUEST FOR INTERPRETATION FMVSS 108; OCC 1383

TEXT: Dear Mr. Hagie:

This is in response to your letter of October 19, 1984, asking for an.. interpretation of Motor Vehicle Safety Standard No. 108 as it relates to motorcycle headlighting systems.

Referencing our letter of July 24, 1984, to Koito in which we confirmed that a motorcycle could be equipped with two headlamps, side by side, each meeting the requirements of SAE J584, you have asked "Does the 75,000 limit (as specified by SAE J584) apply to each lamp individually, or must the total output of both lamps be limited to 75,000 cd?"

SAE J584 states in pertinent part that "The beam or beams from a single lamp shall meet the candle power specifications listed in" Table 1. This table established a maximum of 75,000 candela "anywhere" for a single lamp. This means that the limit applies to each lamp individually under the Koito interpretation.

You have further stated that Kawasaki is considering a headlamp design that consists of two reflectors, each with its own dual-filament bulb, each capable of independent aim installed in a single housing, and behind a single lens. You have asked if such a design is acceptable for a motor-cycle, and whether both reflectors would have to be independently aimable or could the aiming be accomplished by moving the whole lamp assembly.

Your contemplated design is acceptable for motorcycles; SAE J584 refers to a "light source or sources" (see "At-Focus Tests"). However, a two-bulb design in a single housing would have to be designed to meet J584's requirements for a single headlamp including maximum output of 75,000 cd. Further, Standard No. 108 permits independently aimable reflectors, or aim by moving the entire assembly whichever you prefer. All that is required is that the unit meet SAE J566 Headlamp Mountings, January 1960.

I hope that this answers your questions.

Sincerely,