Interpretation ID: aiam3394
Manager
Technical Administration Dept.
Koito Manufacturing Co.
Ltd.
Shizuoka Works
550
Kitawaki
Shimizu- Shi
Shizuika-Ken
Japan;
Dear Mr. Iwase: This is in reply to your letter of February 12, 1981, asking whethe the placement of a clear lens cover in front of a motorcycle headlamp would be permissible under Federal Motor Vehicle Safety Standard No. 108.; SAE Standard J580 (both a and b versions) *Sealed Beam Headlam Assembly* is incorporated by reference in Tables I and III of the standard as one of the standards pertaining to headlamps for use on passenger cars, trucks, buses, and multipurpose passenger vehicles. Paragraph 5.2 of J580 states that, 'When in use, a headlamp shall not have any styling ornament or other feature, such as a glass cover or grill, in front of the lens.'; The principal referenced SAE material for motorcycle headlamps is J584 *Motorcycle Headlamps*. As options, both J584 and S4.1.1.34 of Standard No. 108 allow, in effect, a motorcycle to be equipped with one half of any sealed beam system permissible on four-wheeled motor vehicles. We therefore view the prohibition of J580 as applicable to use of any sealed beam headlamp, regardless of the type of vehicle on which it is installed.; Paragraph S4.1.3 of Standard No. 108 forbids the installation o additional equipment 'that impairs the effectiveness of lighting equipment required' by Standard No. 108. Because of moisture accumulation, discoloration, cracks, etc., a glass or plastic cover might tend over a period of time to diminish or distort the headlamp beam. This is of particular concern with reference to the unsealed headlamps implicitly permitted by SAE J584 because of the tendency of the reflector to deteriorate with age.; The agency therefore has concluded that no motorcycle headlamp may hav a glass shield in front of it when in use.; Sincerely, Frank Berndt, Chief Counsel